Feeling Blue or Seeing Red? Similar Patterns of Emotion Associations With Colour Patches and Colour Terms

For many, colours convey affective meaning. Popular opinion assumes that perception of colour is crucial to influence emotions. However, scientific studies test colour–emotion relationships by presenting colours as patches or terms. When using patches, researchers put great effort into colour presentation. When using terms, researchers have much less control over the colour participants think of. In this between-subjects study, we tested whether emotion associations with colour differ between terms and patches. Participants associated 20 emotion concepts, loading on valence, arousal, and power dimensions, with 12 colours presented as patches (n = 54) or terms (n = 78). We report high similarity in the pattern of associations of specific emotion concepts with terms and patches (r = .82), for all colours except purple (r = .−23). We also observed differences for black, which is associated with more negative emotions and of higher intensity when presented as a term than a patch. Terms and patches differed little in terms of valence, arousal, and power dimensions. Thus, results from studies on colour–emotion relationships using colour terms or patches should be largely comparable. It is possible that emotions are associated with colour concepts rather than particular perceptions or words of colour

Erm(41)-dependent inducible resistance to azithromycin and clarithromycin in clinical isolates of Mycobacterium abscessus

Objectives The ribosomal methylase Erm(41) confers inducible resistance to macrolides in Mycobacterium abscessus. The aim of this work was to systematically study and compare drug susceptibility to clarithromycin and azithromycin in M. abscessus and Mycobacterium chelonae clinical isolates with a particular focus on inducible drug resistance. Methods Clinical isolates of M. abscessus subsp. abscessus (n = 21), M. abscessus subsp. bolletii (n = 16), M. abscessus subsp. massiliense (n = 10) and M. chelonae (n = 22) were characterized regarding their erm(41) and rrl genotypes and subjected to drug susceptibility testing (DST) for clarithromycin and azithromycin. Microdilution DST was performed in cation-adjusted Mueller-Hinton broth (pH 7.4) with readings at days 3, 7 and 12 and with pre-incubation at subinhibitory macrolide concentrations for erm(41) induction. In addition, the influence of variations in pH and growth medium on DST results was examined. Results MICs of azithromycin were consistently higher than those of clarithromycin. In strains with an inducible erm(41) gene, high median MICs of ≥256 mg/L on day 12 were observed for both clarithromycin and azithromycin. Inducible resistance was at least as pronounced for azithromycin as for clarithromycin. Conclusions Our findings do not support the suggestion of a preferential use of azithromycin over clarithromycin in order to limit inducible macrolide resistance. Both compounds provoked a comparable resistance phenotype in M. abscessus. Caution is needed when using either azithromycin or clarithromycin for treatment of M. abscessus infection

Première évaluation du risque toxique lié aux cyanobactéries d'eau douce en France : le programme " EFFLOCYA "

Une enquête menée à l'aide d'un questionnaire couvrant l'ensemble du territoire français ainsi que l'étude spécifique d'écosystèmes aquatiques de type lacs et réservoirs ont permis de montrer que les proliférations de cyanobactéries toxiques pouvaient a priori affecter n'importe quel plan d'eau de l'Héxagone. Les genres rencontrés responsables de la production de toxines, le plus souvent hépatiques, sont Microcystis, Planktothrix, Anabœna et Cylindrospermopsis.Les efflorescences peuvent se produire tout au long de l'année car certaines espèces sont adaptées aux eaux froides et elles ne sont pas liées de manière univoque à un état eutrophe de l'écosystème.La production toxinique est la plus élevée lorsque les populations cyanobactériennes sont peu ou pas diversifiées et à la lumière de travaux récents, cette production serait favorisée, en ce qui concerne les microcystines, par un milieu riche en nitrate, pauvre en ammonium et fortement carencé en fer.La suite à donner à ce travail pourrait être la création d'un observatoire national des efflorescences toxiques.An inquiry covering the whole French territory together with specific studies of natural and artificial reservoirs has been made to assess the human health risk related to the prolifération of toxin producing blue green algae (cyanobacteria). The conclusions show that any lentic ecosystem can be affected like it has been shown already in other countries all over the world and more specifically within the EU. The main genus concemed are: Microcystis, Planktothrix, Anabœna and Cylindrospermopsis.Blooms can occur juring the whole year since some species are well adapted to cold water and are not clearly linked with the trophic status of the aquatic ecosystem.The toxinic production is the largest when the cyanobacteria populations contain only a few number of species. The results of recent works are well correlated with our findings which show that the production of toxic heptapeptides (microcystins) could be correlated with high levels of nitrate and depletions of ammonium and iron.The follow up of this work should now include the set up of a national observatory of toxic algal blooms

Chord distribution functions of three-dimensional random media: Approximate first-passage times of Gaussian processes

The main result of this paper is a semi-analytic approximation for the chord distribution functions of three-dimensional models of microstructure derived from Gaussian random fields. In the simplest case the chord functions are equivalent to a standard first-passage time problem, i.e., the probability density governing the time taken by a Gaussian random process to first exceed a threshold. We obtain an approximation based on the assumption that successive chords are independent. The result is a generalization of the independent interval approximation recently used to determine the exponent of persistence time decay in coarsening. The approximation is easily extended to more general models based on the intersection and union sets of models generated from the iso-surfaces of random fields. The chord distribution functions play an important role in the characterization of random composite and porous materials. Our results are compared with experimental data obtained from a three-dimensional image of a porous Fontainebleau sandstone and a two-dimensional image of a tungsten-silver composite alloy.Comment: 12 pages, 11 figures. Submitted to Phys. Rev.

Structure-property correlations in model composite materials

We investigate the effective properties (conductivity, diffusivity and elastic moduli) of model random composite media derived from Gaussian random fields and overlapping hollow spheres. The morphologies generated in the models exhibit low percolation thresholds and give a realistic representation of the complex microstructure observed in many classes of composites. The statistical correlation functions of the models are derived and used to evaluate rigorous bounds on each property. Simulation of the effective conductivity is used to demonstrate the applicability of the bounds. The key morphological features which effect composite properties are discussed

Molecular approaches for monitoring potentially toxic marine and freshwater phytoplankton species

International audienceHarmful phytoplankton species are a growing problem in freshwater and marine ecosystems, because of their ability to synthesize toxins that threaten both animal and human health. The monitoring of these microorganisms has so far been based on conventional methods, mainly involving the microscopic counting and identification of cells, and using analytical and bioanalytical methods to identify and quantify the toxins. However, the increasing number of microbial sequences in the GeneBank database and the development of new tools in the last 15 years nowadays enables the use of molecular methods for detection and quantification of harmful phytoplankton species and their toxins. These methods provide species-level identification of the microorganisms of interest, and their early detection in the environment by PCR techniques. Moreover, real time PCR can be used to quantify the cells of interest, and in some cases to evaluate the proportion of toxin-producing and non-toxin-producing genotypes in a population. Recently, microarray technologies have also been used to achieve simultaneous detection and semiquantification of harmful species in environmental samples. These methods look very promising, but so far their use remains limited to research. The need for validation for routine use and the cost of these methods still hamper their use in monitoring programs

Un nouveau capteur industriel de mesure du temps de coagulation du lait: le coagulometre

National audienc

Phytoplankton growth control and risk of cyanobacterial blooms in the lower Senegal River delta region

Eutrophication, and the resulting proliferation of phytoplankton can affect water quality. Although environmental and ecological processes that lead to phytoplankton proliferations in temperate areas have received considerable attention, scientific background regarding this topic in tropical areas, especially West Africa, are scarce. In this study, bioassays in batch cultures were carried out in order to identify factors that may be stimulating or limiting the biomass of phytoplankton at various sites in the lower Senegal River delta region. Complete factorial designs were used to test several factors both alone and combined (nitrogen, phosphorus, sulfate, EDTA and trace elements, stirring). The effects of these factors on the growth of the whole phytoplankton communities were followed by the daily measurement of in uivo fluorescence. At all but two of the sites, enrichment with certain nutrients significantly stimulated phytoplankton biomass growth, with nitrogen and/or phosphorus appearing to be the primary limiting factor(s). Nitrogen was the primary limiting factor in coastal ocean waters and in the Senegal River estuary. in the freshwater ecosystems studied, nitrogen and phosphorus acted as alternating or concomitant limiting factors. We assessed the changes in the phytoplankton composition induced by nutrient enrichments in Lake Guiers, a drinking water reservoir for the population of Dakar. Our findings lead us to define the conditions of a possible proliferation of the potentially toxic cyanobacterium Cylindrospermopsis raciborskii mainly in response to phosphorus inputs