Étude comparative des pratiques d’enseignement de la lecture en 4e primaire : des questions de didactique pointées par l’étude internationale PIRLS 2011

Cette étude vise à mettre en lumière des pratiques d‘enseignement de la lecture susceptibles de rendre compte des disparités de performances observées dans différents systèmes éducatifs. Les comparaisons portent sur les pratiques d’enseignement de la lecture déclarées par les enseignant.e.s de huit systèmes éducatifs contrastés tant au plan de la langue enseignée (français, anglais, allemand) qu’au plan des performances moyennes obtenues à l’épreuve PIRLS 2011. Les résultats mettent en évidence des différences parfois importantes dans la fréquence à laquelle sont mises en place certaines facettes de l’enseignement de la lecture et plus spécifiquement de la compréhension. Ces pratiques témoignent de visions contrastées, parfois éloignées de ce que l’on pourrait attendre d’un enseignement de la lecture experte.Peer reviewe

The effect of naloxone treated and naloxone untreated on the cAMP inhibition of 50–11, BE 1–13, BE 1–17, and BE 1–31 in HEK 293 cells expressing DOR.

<p>Naloxone (100 µM) was added to the cells (20000 cells/well) 30 min prior adding opioid peptide and FSK (50 µM) in order to block MOR. The opioid peptides inhibition of the accumulation of cAMP was blocked by pre-treatment with naloxone. In naloxone treated cells cAMP levels were significantly higher than those in absence of naloxone (*<i>P<0.05</i>), one-way anova, post-test newman-keuls multiple comparison test). Values represent mean ± SEM of at least three independent experiments. Values represent mean ± SEM of at least three independent experiments. FSK: No opioid peptide. STIM: No opioid peptide and no FSK.</p

BE fragments IC50 for the inhibition of forskolin induced cAMP in HEK-MOP cells.

<p>BE fragments IC50 for the inhibition of forskolin induced cAMP in HEK-MOP cells.</p

Biotransformation of BE 1–17 in homogenised inflamed tissue at 37°C.

<p><b>A</b>. The TIC spectra of BE 1–17 and its fragments detected after 45 minutes incubation at 37°C with inflamed tissue at pH 5.5. <b>B</b>. Peak <b>a</b> at retention time of 17.6 minutes is BE 1–11 with following observed mass/charge values [M+H]⁺¹:1235.2 and [M+H]⁺²: 618.2. <b>C</b>. Peak b at retention time of 18.6 minutes is BE 1–13 with following observed mass/charge values [M+H]⁺¹:1433.3 and [M+H]⁺²: 717.4.</p

BE fragments IC50 for the inhibition of forskolin induced cAMP in HEK-DOP cells.

<p>BE fragments IC50 for the inhibition of forskolin induced cAMP in HEK-DOP cells.</p

Chromatographic analysis gradients used for solvents A and B in the separation of beta-endorphin fragments.

<p>Chromatographic analysis gradients used for solvents A and B in the separation of beta-endorphin fragments.</p

Screening of BE 1–31 and its metabolites on cAMP inhibition in HEK 293 cells expressing KOR (10 nM and 1 µM).

<p>The screening of BE 1–31 and its fragments were performed by using 1000 cells/well with FSK (300 µM) to investigate the effect of BE 1–31 and its fragments on activation of KOP by measuring the level of cAMP. Values represent mean ± SEM of at least three independent. BE 1–31 and its fragments had limited activity at KOR modulation of cAMP.</p

Biotransformation of BE 1–17 in inflamed tissue at pH 5.5 at 37°C over 60 minutes.

<p>The production and degradation of BE 1–9, BE 2–9, BE 1–11, BE 2–11, BE 1–13, BE 2–13 during incubation of BE 1–17 in inflamed tissue at pH 5.5 at 37°C over 60 minutes. The peak area of each fragment was determined at each time point and plotted.</p

Chromatograms and mass spectra relating to the detection of rifamycin O.

<p>(<b>A</b>) LC-QToF-MS Total Ion Chromatogram (TIC) for <i>S. arenicola</i> strain MV0472 and (<b>B</b>) Mass spectrum of peak X and (<b>C</b>) Chromatogram for rifamycin O standard and (<b>D</b>) Mass spectrum of peak X (lower 2 panels). The retention times of X and rifamycin O standard are 24.5 and 24.55 min, respectively. The <i>m/z</i> of molecular ion of X and rifamycin O standards are 752.2985 and 752.2954.</p

Identification of species-specific compounds in extracts of <i>S. arenicola</i> and <i>S. pacifica</i> by UHPLC-QToF-MS and PCA.

<p>(A) Total ion current (TIC) chromatograms of <i>S. arenicola</i> and (B) <i>S. pacifica</i> (C) TICs from the same (<i>S. arenicola</i>) subset of samples (three replicates) to highlight the reproducibility of acquisition. For ease of interpretation, chromatograms of 2 to 24 minutes are shown to illustrate the period of chromatography during which most compounds elute. Full chromatograms for both species are available in the Supplementary information (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0091488#pone.0091488.s006" target="_blank">Figure S6</a>). (D) Principal component analysis (PCA) scores plot, PC1 (t<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0091488#pone.0091488-Paul1" target="_blank">[1]</a>) versus PC2 (t<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0091488#pone.0091488-Phelan1" target="_blank">[2]</a>) showing the variation in the profiles of secondary metabolites from two species: <i>S. arenicola</i> (A, blue) and <i>S. pacifica</i> (P, red). Each symbol represents one bacterial strain described by all detected metabolites. (E) Inspection of the 2-D loadings plot for PC1 vs. PC2 reveals the variables responsible for the spatial arrangement of samples. (F) Extracted ion chromatogram (EIC) of <i>m/z</i> 754.3092 from both species, showing clear species differences in the abundance of this metabolite <i>S. arenicola</i> (blue) and <i>S. pacifica</i> (red). (G) MS spectrum for EIC peak. (H) Box-and-whisker plot of the abundance of the 754 ion in the two species (P<.0001).</p