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31.
European Journal of Psychology of Education - 相似文献
32.
Rupprecht P Golé L Rieu JP Vézy C Ferrigno R Mertani HC Rivière C 《Biomicrofluidics》2012,6(1):14107-1410712
We have developed a method for studying cellular adhesion by using a custom-designed microfluidic device with parallel non-connected tapered channels. The design enables investigation of cellular responses to a large range of shear stress (ratio of 25) with a single input flow-rate. For each shear stress, a large number of cells are analyzed (500–1500 cells), providing statistically relevant data within a single experiment. Besides adhesion strength measurements, the microsystem presented in this paper enables in-depth analysis of cell detachment kinetics by real-time videomicroscopy. It offers the possibility to analyze adhesion-associated processes, such as migration or cell shape change, within the same experiment. To show the versatility of our device, we examined quantitatively cell adhesion by analyzing kinetics, adhesive strength and migration behaviour or cell shape modifications of the unicellular model cell organism Dictyostelium discoideum at 21 °C and of the human breast cancer cell line MDA-MB-231 at 37 °C. For both cell types, we found that the threshold stresses, which are necessary to detach the cells, follow lognormal distributions, and that the detachment process follows first order kinetics. In addition, for particular conditions’ cells are found to exhibit similar adhesion threshold stresses, but very different detachment kinetics, revealing the importance of dynamics analysis to fully describe cell adhesion. With its rapid implementation and potential for parallel sample processing, such microsystem offers a highly controllable platform for exploring cell adhesion characteristics in a large set of environmental conditions and cell types, and could have wide applications across cell biology, tissue engineering, and cell screening. 相似文献
33.
This article presents the Δ-distance, a family of distances between images recursively decomposed into segments and represented by multi-level feature vectors. Such a structure is a quad, a quin or a nona-tree resulting from a fixed and arbitrary image partition or from an image segmentation process. It handles positional information of image features (e.g. color, texture or shape). Δ-distance is the generalized form of dissimilarity measures between multi-level feature vectors. Using different weights on tree nodes and different distances between nodes, distances between trees or visual similarity between images can be computed based on the general definition of Δ. In this article, we present three Δ-based distance families: two families of distances between tree structures, called
-distance( for Tree) and
-distance ( for Segment), and a family of visual distances between images, called ( for Visual). The -distance visually compares two images using their tree representation and the other two distances compare the tree structures resulting from image segmentation. Moreover, we show how existing distances between multi-level feature vectors appear to be particular cases of the Δ-distance 相似文献
34.
35.
Marie Simon Lauren A. Fromont Marie-Thérèse Le Normand 《Scientific Studies of Reading》2013,17(6):494-508
ABSTRACTThis study aims to compare word spelling outcomes for French-speaking deaf children with a cochlear implant (CI) with hearing children who matched for age, level of education and gender. A picture written naming task controlling for word frequency, word length, and phoneme-to-grapheme predictability was designed to analyze spelling productions. A generalized linear mixed model on the percentage of correct spelling revealed an effect of participant’s reading abilities, but no effect of hearing status. Word frequency and word length, but not phoneme-to-grapheme predictability, contributed to explaining the spelling variance. Deaf children with a CI made significantly less phonologically plausible errors and more phonologically unacceptable errors when compared to their hearing peers. Age at implantation and speech perception scores were related to deaf children’s errors. A good word spelling level can be achieved by deaf children with a CI, who nonetheless use less efficiently the phoneme-to-grapheme strategy than do hearing children. 相似文献
36.
Adriana Bernardi Francesca Becherini Marco Verità Patrick Ausset Maura Bellio Ulrike Brinkmann Helene Cachier Anne Chabas Felix Deutsch Marie-Pierre Etcheverry Franco Geotti Bianchini Ricardo H.M. Godoi Velichka Kontozova-Deutsch Roger Lefèvre Tiziana Lombardo Peter Mottner Chiara Nicola Isabelle Pallot-Frossard René Van Grieken 《Journal of Cultural Heritage》2013,14(6):527-536
The methodology of protecting the European stained glass windows against environmental risk (e.g. meteorological factors, air pollution, microorganisms) by means of an external glazing is not new. In spite of many scientific studies carried out in the last 20 years, some questions were still up for discussion. The European VIDRIO (2002–2005) project gave an answer to these questions. The research carried out by the different project partners established a new multidisciplinary approach aimed at evaluating the efficiency of the protective glazing systems and their effects on stained glass windows conservation, and finally at assessing the most appropriate strategy to preserve stained glass windows. Scientific results showed that the so-called isothermal glazing (i.e. ventilation by the air coming from the inside of the building) protected efficiently the ancient stained glass window from environmental attack (i.e. rain, pollutants, condensation, thermal shocks) with very limited secondary effects. The scientific research highlighted that its efficiency was strongly related to the technical design of the protective system. In particular, the ventilation and the size of the interspace had to be carefully considered. The research developed within the VIDRIO project was turned into general recommendations to the owners and practitioners on the best practice for the stained glass windows future conservation. 相似文献
37.
In this paper, the authors report on the importance of using Intensive Interaction for the development of non-verbal communication for people with autism. The complexity of learning non-verbal communication means that it cannot be taught in any sense in a traditional, didactic manner. While a person may have the cognitive abilities to follow instructions and be taught the need to behave a certain way in social situations, which will not allow them to properly assimilate and understand social expectations and how to operate in social contexts. This paper suggests that the use of Intensive Interaction creates frequent opportunities for a person to take part in face-to-face interactions and consequently allow for the gradual development of non-verbal communication. 相似文献
38.
Learning environments at the margin: Case studies of disenfranchised youth doing science in an aquarium and an after-school program 总被引:1,自引:0,他引:1
In this article, we explore how two informal educational contexts—an aquarium and an after-school science program—enabled
disenfranchised learners to adopt an identity as insiders to the world of science. We tell the stories of four youth, relating
what doing science meant to them and how they positioned themselves in relation to science. We contribute to the extensive
literature on the value of learning beyond the school walls, yet focus on ethnically and linguistically diverse youth from
low-income backgrounds who have often been excluded from such settings. We suggest that such out-of-school settings are particularly
important to youth who have few other opportunities to interact with and relate to science in positive ways. 相似文献
39.
Research in Science Education - The aim of this paper is to show how an innovative technique can be used to introduce a method for uncovering intrinsic mechanisms that motivate changes in... 相似文献
40.
The construction of nomographs for transitional classical filters is described. Gain functions of classical filters are related to filter requirements resulting in a formulation for the general gain nomograph. The transitional filters that are products of approximating polynomials are incorporated into the general gain nomograph resulting in transitional filter nomographs that are sums of the individual nomographs. Nomographs for transitional filters using alternative forms where poles are interpolated are also considered. The resulting nomographs allow for quick optimization of transitional filter frequency response in many cases. Design examples are submitted and discussed. The proposed transitional filter nomographs provide the engineer with increased insight into the selection of classical transitional filters with optimum frequency response. 相似文献