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Infant vocalizations are early-emerging communicative markers shown to be atypical in autism spectrum disorder (ASD), but few longitudinal, prospective studies exist. In this study, 23,850 infant vocalizations from infants at low (LR)- and high (HR)-risk for ASD (HR-ASD = 23, female = 3; HR-Neg = 35, female = 13; LR = 32, female = 10; 80% White; collected from 2007 to 2017 near Philadelphia) were analyzed at 6, 12, and 24 months. At 12 months, HR-ASD infants produced fewer vocalizations than HR-Neg infants. From 6 to 24 months, HR-Neg infants demonstrated steeper vocalization growth compared to HR-ASD and LR infants. Finally, among HR infants, vocalizing at 12 months was associated with language, social phenotype, and diagnosis at age 2. Infant vocalizing is an objective behavioral marker that could facilitate earlier detection of ASD.  相似文献   
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Shear stress is the major mechanical force applied on vascular endothelial cells by blood flow, and is a crucial factor in normal vascular physiology and in the development of some vascular pathologies. The exact mechanisms of cellular mechano-transduction in mammalian cells and tissues have not yet been elucidated, but it is known that mechanically sensitive receptors and ion channels play a crucial role. This paper describes the use of a novel and efficient microfluidic device to study mechanically-sensitive receptors and ion channels in vitro, which has three independent channels from which recordings can be made and has a small surface area such that fewer cells are required than for conventional flow chambers. The contoured channels of the device enabled examination of a range of shear stresses in one field of view, which is not possible with parallel plate flow chambers and other previously used devices, where one level of flow-induced shear stress is produced per fixed flow-rate. We exposed bovine aortic endothelial cells to different levels of shear stress, and measured the resulting change in intracellular calcium levels ([Ca2+]i) using the fluorescent calcium sensitive dye Fluo-4AM. Shear stress caused an elevation of [Ca2+]i that was proportional to the level of shear experienced. The response was temperature dependant such that at lower temperatures more shear stress was required to elicit a given level of calcium signal and the magnitude of influx was reduced. We demonstrated that shear stress-induced elevations in [Ca2+]i are largely due to calcium influx through the transient receptor potential vanilloid type 4 ion channel.  相似文献   
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Students’ writing problems are a global educational concern and is in need of particular attention. This study aims to examine the impact of providing extra writing opportunities (i.e., writing journals) on the quality of writing compositions. A longitudinal cluster-randomized controlled design using a multilevel modeling analysis with 182 fourth grade students was conducted. We examined whether students’ writing quality differed when writing journals on a weekly basis for 12 weeks, compared with a control group. Three covariates were analyzed, namely: (i) the students’ attitudes towards writing; (ii) their self-efficacy in writing; (iii) and their use of self-regulation (SRL) strategies while writing. Findings have shown that students who wrote week-journals significantly improved the writing quality of their compositions and reported a higher use of SRL strategies in writing. Nevertheless, self-efficacy and attitude towards writing were found to not be related to the quality of the compositions. Moreover, data indicated that the writing quality of compositions improved along with the writing quality of the week-journals. Findings suggest the use of week-journals in class to promote writing.  相似文献   
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This study used eye-tracking methodology to assess audiovisual speech perception in 26 children ranging in age from 5 to 15 years, half with autism spectrum disorders (ASD) and half with typical development. Given the characteristic reduction in gaze to the faces of others in children with ASD, it was hypothesized that they would show reduced influence of visual information on heard speech. Responses were compared on a set of auditory, visual, and audiovisual speech perception tasks. Even when fixated on the face of the speaker, children with ASD were less visually influenced than typical development controls. This indicates fundamental differences in the processing of audiovisual speech in children with ASD, which may contribute to their language and communication impairments.  相似文献   
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The objective of this research study is to offer a glimpse into the lives of some newly-arrived students of different racial, linguistic and religious backgrounds as they confront the process of immigration and therefore personal and social displacement within the context of a Toronto inner-city high school. These students carry with them hidden but enduring scars that influence all aspects of their educational lives. In many cases their experience is steeped in trauma. Using auto-ethnographic methodology, this research is devoted to giving voice to these students who inhabit a space filled with suffering and loss but also resilience and cautious hope. If we really care about these vulnerable students in our classrooms, we must rethink and reshape our understanding of teaching and learning that is more fundamentally linked to the lived experiences of students coming from places of war and other oppressions. These issues are crucial for the future of nation-building and citizenship education in pluralistic Western societies such as Canada, both in and out of school.  相似文献   
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According to the literature, there is a very important corpus of knowledge that allows for the investigation of some dimensions of ‘learning experience’ provided to students, in relation to epistemic, pedagogical and meta-cognitive practices. However, in the literature, there is little investigation into the invariance (or not) of the characteristics of students’ learning experience while being taught a scientific subject by the same teacher. This paper suggests that the relationship between the learning experience provided and the competences developed is not properly highlighted. This paper analyses the learning experience provided to students in epistemic, pedagogical and meta-cognitive terms. The students were taught the proprieties and applications of light by one teacher, in three classes, over 7 weeks. We analysed the data in each referred learning experience, using a pre-defined category system. The students’ competences were evaluated by a competence test. The epistemic demand of each item and the students’ performances were also analysed. Our findings point to the non invariance of learning experiences provided to students and the influence of some dimensions of learning experiences provided in the development of certain competences. These findings and their implications are contextualized and discussed.  相似文献   
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