This research examines the joint effect of interactive reading through the didactic vocabulary model Viertakt and electronic storybooks on vocabulary development. In addition, possibilities for...Show moreThis research examines the joint effect of interactive reading through the didactic vocabulary model Viertakt and electronic storybooks on vocabulary development. In addition, possibilities for differentiation in word learning education are investigated. The goal of this research was to maximize word development of preschool children and to reduce differences in vocabulary. The study involved 52 Dutch preschool children (50% girl, 50% boy) aged 48-71 months and consisted of a classroom reading intervention and an individual differentiation reading intervention. The participants were divided into four subgroups. Throughout the classroom reading intervention, a within-subject design exposed all participants to the following four conditions: without Viertakt, with Viertakt and phonological consolidation, with Viertakt and phonological and semantic consolidation, and the control condition. The individual differentiation reading intervention consisted of a between-subjects design. Half of the participants who benefited the least from the classroom reading intervention, were assigned to two conditions: differentiation whilst actively answering questions and differentiation without answering questions. The findings indicated that preschool children achieve a significantly bigger vocabulary from the classroom reading intervention with Viertakt compared to the classroom reading without Viertakt. Their vocabulary grew equally in both forms of consolidation. The preschool children possessed a bigger vocabulary after the individual differentiation reading intervention, however it is not certain whether the growth in vocabulary was due to the differentiation or also as a result of consolidation over time. Actively questioning helped the preschool children to improve their vocabulary. Altogether, the classroom reading intervention leads to a greater vocabulary and the individual differentiation reading intervention diminishes the pre-existing differences between children. Further research, including a control group for the differentiation, is needed to investigate the effect of the differentiation on vocabulary development.Show less
One of the biggest challenges in embryonic stem (ES) cell biology is to replicate the organized structure that an embryo develops in vivo: ES cell differentiation in vitro is disorganized and...Show moreOne of the biggest challenges in embryonic stem (ES) cell biology is to replicate the organized structure that an embryo develops in vivo: ES cell differentiation in vitro is disorganized and highly variable. This study presents a micropattering technique to study organized differentiation of mouse embryonic stem cells (mESC) into the germ layers. Microcontact printing is used to create a patterning of circular spots on a flat substrate to confine colony growth. This confinement triggers a spatial patterning of germ layers inside the colonies. We found that after 6 days of differentiation, mESC colonies on a micropattern of laminin or collagen express Sox17, indicating endoderm, in cells near the edge of a 200-300 m diameter colony. Brachyury, a mesoderm marker, is expressed around the center. Future research should investigate ways to optimize colony geometry control during differentiation.Show less
