Validation et consistance interne d’une batterie de tests pour l’évaluation multidimensionnelle de la lecture en français

Nous présentons les considérations théoriques qui guident l’élaboration de la batterie de tests destinée à l’évaluation de la lecture en français. Ensuite, nous étayons les cinq domaines ciblés par la Batterie d’épreuves multidimensionnelles pour l’évaluation de la lecture (BÉMÉL) : a) la sensibilité phonologique, b) les connaissances alphabétiques, c) l’identification des mots réels ou inventés, d) la sensibilité grammaticale, e) la compréhension des phrases et des textes. Nous rapportons les résultats d’une étude sur huit échelles de mesure représentant trois de ces domaines. Ces résultats attestent que la consistance interne des échelles est satisfaisante et que l’augmentation de la performance en fonction du niveau scolaire appuie la validité des concepts représentés par ces échelles. Nous concluons avec quelques observations sur le développement à venir.The authors present the theoretical underpinnings used in the development of a battery of tests to evaluate reading in French. The five areas targeted by the “Batterie d’épreuves multidimensionnelles pour l’évaluation de la lecture” (BÉMÉL) include: a) phonologic sensitivity, b) alphabet knowledge, c) identification of real and invented words, d) grammatical awareness, e) comprehension of sentences and text. Presented are the results of a study of eight measurement scales representing three of these areas. The results show that the internal reliability of these scales is satisfactory and that the improvement in performance at each school level supports the validity of the concepts represented by these scales. The authors conclude with several observations regarding future development.Presentamos las consideraciones teóricas que orientan la elaboración de la batería de tests que tiene por objetivo la evaluación de la lectura en francés. A continuación apuntalamos los cinco dominios enfocados para la Batería de pruebas multidimensionales para la evaluación de la lectura (BEMEL): a) la sensibilidad fonológica, b) los conocimientos alfabéticos, c) la identificación de las palabras reales o inventadas, d) la sensibilidad gramatical, e) la comprensión de las frases y de textos. Informamos de los resultados de un estudio basado en ocho escalas de medida que representan tres de estos dominios. Estos resultados confirman que la consistencia interna de las escalas es satisfactoria y que el incremento del rendimiento según el nivel escolar sostiene la validez de los conceptos representados por estas escalas. Concluimos con algunas observaciones sobre el desarrollo a futuro

Interference effects in two-photon ATI by multiple orders high harmonics with random or locked phases

We numerically study 2-photon processes using a set of harmonics from a Ti:Sapphire laser and in particular interference effects in the Above Threshold Ionization spectra. We compare the situation where the harmonic phases are assumed locked to the case where they have a random distribution. Suggestions for possible experiments, using realistic parameters are discussed.Comment: 11 pages, 13 figures, LaTe

Développement d’un test d’analyse auditive en français : normes et validation de construit

Deux études ont permis de développer, en français, un instrument qui sert à mesurer les habiletés de segmentation des mots prononcés en leurs éléments sonores, chez des enfants de la maternelle à la sixième année, habiletés jugées cruciales pour l'apprentissage de la lecture. Une première étude qui portait sur un large échantillon d'items (n = 70) a servi à la création de deux listes de 42 items chacune, formant deux versions d'un même test, pour une deuxième étude. Les résultats des deux études montrent que les caractéristiques psychométriques - fidélité et validité - de l'instrument développé sont très élevées. De plus, dans la deuxième étude, la performance des sujets ne différait pas selon la version du test. Ces résultats appuient l'utilisation de ce test dans les milieux scolaires pour l'identification de troubles d'analyse auditive chez les enfants qui ont des problèmes de lecture.This article reports on two studies used to develop a French language test to measure oral word-segmentation ability in children from Kindergarten to Grade 6; this ability being considered important in learning to read. The first study of a large sample of items (n = 70) was used to create two lists of 42 items each, to form equivalent versions of the same test, and then used in a second study. The results of the two studies show that the psychometric characteristics of the instrument, that of reliability and validity, are very high. As well, it was found that performance of subjects did not differ with the test version used. These results support use of this test in school settings to identify auditive analysis difficulties in children who have reading difficulties.Dos estudios, han permitido crear un instrumento en francès, para medir la habilidad de los nifios para separar las palabras en fonemas. Esta habilidades considerada importante en el proceso del aprendizaje de la lectura. El instrumento puede aplicarse a nifios disde la escuela de parvulos hasta el 6° ano de primari. El primer estudio comprendié un gran numéro de cuestiones (n = 70) y sirvio para la confection de dos listas de 42 preguntas cada una; se obtuveron asi dos versiones de un mismo test que constituyeron la base del segundo estudio. Los resultados de los dos estudios muestran que las caractensticas psocométricas - fidelidad y validez - del instrumento son bastante elevadas. Ademâs, en el segundo estudio se destaca que el resultado obtenido por no deflene mucho entre las dos versiones. Creemos que esos resultados avalan la utilizaciôn de este test en el medio escolar para identificar problemas de analisis auditivo en nifios con dificultades en el aprendizaje de la lectura.Zwei Studien haben erlaubt, fur die franzôsische Sprache ein Instrument zu entwickeln zur Messung der Fâhigkeit, gesprochene Worter in ihre Lautelemente zu zerlegen, und zwar bei Kindern von der Vorschule vis zur 6.Volksschulklasse. Dièse Fâhigkeit gilt als àuÊerst wichtig fur das Lesenlernen. Eine erste Untersuchung iiber eine grofie Anzahl von Einheiten (n = 70) fiihrte zur Erstellung zweier Listen mit je 42 Einheiten, welche zwei Versionen des gleichen Tests darstellten fiir eine zweite Untersuchung. Die Ergebnisse der beiden Studien zeigen, dass die psychometrischen Qualitâten, nâmlich Genauigkeit und Giiltigkeit, des entwickelten MeCinstrumentes sehr hoch sind. Aufierdem war die Leistung der Versuchspersonen in den beiden Tests nicht verschieden. Dièse Ergebnisse sprechen fur die Anwendung dieses Tests im Schulmilieu, um Schwierigkeiten in der Lautanalyse bei Kindern mit Leseschwierigkeiten zu identifizieren

Denudation of the Côte d'Ivoire-Ghana transform margin from apatite fission tracks.

Apatite fission track analysis of samples from the shoulder (marginal ridge) of the Côte d'Ivoire-Ghana transform continental margin reveal a cooling of the margin between 85 and 65 Ma for the central and eastern parts of the ridge. All samples were heated in situ during sedimentary burial with a temperature >120 °C, except for two samples located in the eastern part which were heated between 105 and 120 °C. For the first time, age/depth diagram along a transform margin shows a shape involving erosion starting at the bottom of the continental slope, then stepping backwards towards the edge of the slope. This retrogressive erosion can result from the deepening of the lithospheric plate sliding along the transform margin, from thick continental crust to thin continental crust, and finally to oceanic crust. This process could be at the origin of the shoulder uplift by flexural response to the important crustal discharge (>2 km)

Effects of FADS and ELOVL polymorphisms on indexes of desaturase and elongase activities: results from a pre-post fish oil supplementation

Polymorphisms (SNPs) within the FADS gene cluster and the ELOVL gene family are believed to influence enzyme activities after an omega-3 (n-3) fatty acid (FA) supplementation. The objectives of the study are to test whether an n-3 supplementation is associated with indexes of desaturase and elongase activities in addition to verify whether SNPs in the FADS gene cluster and the ELOVL gene family modulate enzyme activities of desaturases and elongases. A total 208 subjects completed a 6-week supplementation period with 5 g/day of fish oil (1.9–2.2 g/day of EPA ? 1.1 g/day of DHA). FA profiles of plasma phospholipids were obtained by gas chromatography (n = 210). Desaturase and elongase indexes were estimated using product-to-precursor ratios. Twenty-eight SNPs from FADS1, FADS2, FADS3, ELOVL2 and ELOVL5 were genotyped using TaqMan technology. Desaturase indexes were significantly different after the 6-week n-3 supplementation. The index of d-5 desaturase activity increased by 25.7 ± 28.8 % (p\0.0001), whereas the index of d-6 desaturase activity decreased by 17.7 ± 18.2 % (p\0.0001) post-supplementation. Index of elongase activity decreased by 39.5 ± 27.9 % (p\0.0001). Some gene–diet interactions potentially modulating the enzyme activities of desaturases and elongases involved in the FA metabolism post-supplementation were found. SNPs within the FADS gene cluster and the ELOVL gene family may play an important role in the enzyme activity of desaturases and elongases, suggesting that an n-3 FAs supplementation may affect PUFA metabolism

Changes in plasma phospholipid fatty acid patterns and their impact on plasma triglyceride levels following fish oil supplementation

The objective of the present study was to test for associations between changes in fatty acids (FAs) and changes in plasma triglyceride (TG) levels after an n-3 FA supplementation and to test whether SNPs from the FADS gene cluster were associ-ated with plasma FA levels or with specific FA patterns. A total of 210 subjects completed a 2-wk run-in period followed by 6-wk supplementation with 5g/d of fish oil. FA profiles of plasma phospholipids (PPLs) were obtained and 19 SNPs from the FADS gene cluster were genotyped. Principal component analysis was conducted and scores were calculated. There was an increase in EPA, DPA and DHA levels in PPLs as well as a decrease in ALA and all n-6 FA levels after the supplementa-tion. Factor analysis suggested 4 post-n-3 FA supplementation patterns. Changes in AA, ALA, DGLA, as well as changes in total n-3 and omega-6 FAs in absolute quantities of FAs were all associated with a change in TG levels whereas the cor-relation remained significant only for AA and DGLA when FAs were expressed as percentage of total FAs. Several SNPs from the FADS gene cluster were associated with post-supplementation FA levels. These results suggest that FAs alone or regrouped in factors could play a role in modulating plasma TG levels after fish oil supplementation. SNPs from the FADSgene cluster interact with both FAs and/or factors to modulate TG levels

Gene expression profile of androgen modulated genes in the murine fetal developing lung

<p>Abstract</p> <p>Background</p> <p>Accumulating evidences suggest that sex affects lung development. Indeed, a higher incidence of respiratory distress syndrome is observed in male compared to female preterm neonates at comparable developmental stage and experimental studies demonstrated an androgen-related delay in male lung maturation. However, the precise mechanisms underlying these deleterious effects of androgens in lung maturation are only partially understood.</p> <p>Methods</p> <p>To build up a better understanding of the effect of androgens on lung development, we analyzed by microarrays the expression of genes showing a sexual difference and those modulated by androgens. Lungs of murine fetuses resulting from a timely mating window of 1 hour were studied at gestational day 17 (GD17) and GD18, corresponding to the period of surge of surfactant production. Using injections of the antiandrogen flutamide to pregnant mice, we hunted for genes in fetal lungs which are transcriptionally modulated by androgens.</p> <p>Results</p> <p>Results revealed that 1844 genes were expressed with a sexual difference at GD17 and 833 at GD18. Many genes were significantly modulated by flutamide: 1597 at GD17 and 1775 at GD18. Datasets were analyzed by using in silico tools for reconstruction of cellular pathways. Between GD17 and GD18, male lungs showed an intensive transcriptional activity of proliferative pathways along with the onset of lung differentiation. Among the genes showing a sex difference or an antiandrogen modulation of their expression, we specifically identified androgen receptor interacting genes, surfactant related genes in particularly those involved in the pathway leading to phospholipid synthesis, and several genes of lung development regulator pathways. Among these latter, some genes related to Shh, FGF, TGF-beta, BMP, and Wnt signaling are modulated by sex and/or antiandrogen treatment.</p> <p>Conclusion</p> <p>Our results show clearly that there is a real delay in lung maturation between male and female in this period, the latter pursuing already lung maturation while the proper is not yet fully engaged in the differentiation processes at GD17. In addition, this study provides a list of genes which are under the control of androgens within the lung at the moment of surge of surfactant production in murine fetal lung.</p