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

Chromatography of <i>Carica papaya</i> leaf extracts.

<p>(A) Base Peak Chromatograms (BPC) of leaf juice, brewed leaf juice, leaf decoction in positive mode and (B) in negative mode; (C) BPCs from the three replicates of leaf juice samples in positive mode and (D) in negative mode. The chromatographic region between 2 to 45 min is shown as it contained almost all of the chromatographic peaks.</p

Multivariate analysis of positive ionisation LC-MS data from <i>Carica papaya</i> leaf extracts.

<p>(A) PCA scores plot, PC1 [t1] versus PC2 [t2] generated from three extracts–Leaf juice (LJ, red triangle), leaf decoction (LD, blue square) and brewed leaf juice (BLJ, green circle). Each symbol represents one replicate. (B) OPLS-DA scores plot of predictive component t[1] versus orthogonal component t₀[1]. The ellipse in (A) and (B) represents the Hotelling’s T² 95% confidence interval for the multivariate data. (C) Loadings plot derived from (B); the variables with higher abundance in LJ than BLJ/LD are highlighted in red with an arrow indicating mass [email protected] minutes. (D) Extracted ion chromatogram (EIC) of m/z 518.374 at retention time 16.559 mins. (E) Mass spectrum for EIC peak.</p

Multivariate analysis of negative ionisation LC-MS data from <i>Carica papaya</i> leaf extracts.

<p>(A) PCA scores plot, PC1 [t1] versus PC2 [t2] generated from three extracts–Leaf juice (LJ, red triangle), leaf decoction (LD, blue square) and brewed leaf juice (BLJ, green circle). Each symbol represents one replicate. (B) OPLS-DA scores plot of predictive component t[1] versus orthogonal component t₀[1]. The ellipse in (A) and (B) represents the Hotelling’s T² 95% confidence interval for the multivariate data. (C) Loadings plot derived from (B); the variables with higher abundance in LJ than BLJ/LD are highlighted in red.</p

Comparison of feature [email protected] in leaf juice against authentic standard pheophorbide A.

<p>(A) BPC chromatogram of leaf juice. (B) BPC chromatogram of pheophorbide A standard. (C) EIC of m/z 593.2752 for leaf juice. (D) EIC of m/z 593.2752 for pheophorbide A standard. (E) Mass spectrum of peak X in leaf juice. (F) Mass spectrum of pheophorbide A standard peak. (G) MS/MS spectrum of peak X in leaf juice. (H) MS/MS spectrum of pheophorbide A standard peak.</p

Effect of <i>Carica papaya</i> leaf extracts on the survival of SCC25 and HaCaT cells.

<p>(A) Leaf juice, (B) Brewed leaf juice, (C) Leaf decoction. Results are shown as mean ± SEM (n = 3). *, <i>p</i><0.05; **, <i>p</i><0.01; ***, <i>p</i><0.001, HaCaT <i>vs</i> SCC25 (two-way ANOVA with Bonferroni post-test).</p

Authentic standard comparison of putative compounds in leaf juice with available reference compounds.

<p>Authentic standard comparison of putative compounds in leaf juice with available reference compounds.</p

Effect of <i>Carica papaya</i> leaf extracts on the survival of SCC25 cancer cells.

<p>The cell viability was determined by the MTT assay and calculated by comparison with the control cells (exposed to medium without extracts). Results are shown as mean ± SEM (n = 3).</p

(A) Effect of pheophorbide A on the survival of SCC25 cancer cells *, <i>p</i><0.05; **, <i>p</i><0.01; ***, <i>p</i><0.001, <i>vs</i> control cells (one-way ANOVA with Dunnett’s test). (B) Effect of pheophorbide A on the survival of SCC25 and HaCaT cells.

<p>*, <i>p</i><0.05; **, <i>p</i><0.01; ***, <i>p</i><0.001, HaCaT <i>vs</i> SCC25 (two-way ANOVA with Bonferroni post-test). Results are shown as mean ± SEM (n = 3).</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