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911.
The structure and function of biological systems, for example, cells and proteins, depend strongly on their chemical environment. To investigate such dependence, we design a polydimethylsiloxane-based microfluidic device to encapsulate biological systems in picoliter-sized drops. The content of each individual drop is tuned in a defined manner. As a key feature of our method, the individual chemical composition is determined and related to the drop content. In our case, the drop content is imaged using microscopy methods, while the drops are immobilized to allow for long-time studies. As an application of our device, we study the influence of divalent ions on vimentin intermediate filament networks in a quantitative way by tuning the magnesium concentration from drop to drop. This way we are able to directly image the effect of magnesium on the fluorescently tagged protein in a few hundreds of drops. Our study shows that with increasing magnesium concentration in the drops, the compaction of the networks becomes more pronounced. The degree of compaction is characterized by different morphologies; freely fluctuating networks are observed at comparatively low magnesium concentrations of 5–10 mM, while with increasing magnesium concentration reaching 16 mM they develop into fully aggregated networks. Our approach demonstrates how a systematic study of interactions in biological systems can benefit from the exceptional controllability of microfluidic methods. 相似文献
912.
Dorothy V. M. Bishop David McDonald Sarah Bird Marianna E. Hayiou-Thomas 《Child development》2009,80(2):593-605
Some children learn to read accurately despite language impairments (LI). Nine- to 10-year-olds were categorized as having LI only ( n = 35), dyslexia (DX) only ( n = 73), LI + DX ( n = 54), or as typically developing (TD; n = 176). The LI-only group had mild to moderate deficits in reading comprehension. They were similar to the LI + DX group on most language measures, but rapid serial naming was superior to the LI + DX group and comparable to the TD. For a subset of children seen at 4 and 6 years, early phonological skills were equally poor in those later classified as LI or LI + DX. Poor language need not hinder acquisition of decoding, so long as rapid serial naming is intact; reading comprehension, however, is constrained by LI. 相似文献
913.
Sarah Roseberry Kathy Hirsh-Pasek Julia Parish-Morris Roberta M. Golinkoff 《Child development》2009,80(5):1360-1375
The availability of educational programming aimed at infants and toddlers is increasing, yet the effect of video on language acquisition remains unclear. Three studies of 96 children aged 30–42 months investigated their ability to learn verbs from video. Study 1 asked whether children could learn verbs from video when supported by live social interaction. Study 2 tested whether children could learn verbs from video alone. Study 3 clarified whether the benefits of social interaction remained when the experimenter was shown on a video screen rather than in person. Results suggest that younger children only learn verbs from video with live social interaction whereas older children can learn verbs from video alone. Implications for verb learning and educational media are discussed. 相似文献
914.
Debate continues regarding the nature and desirability of graduate attributes, driven partly by stakeholder expectations that universities will prepare employees for the knowledge economy and partly by higher education academics and learning specialists. While universities appear to have accepted their new vocational role, there is considerable confusion over how these things – graduate skills, attributes or capabilities – should be defined and implemented. Conceptual confusion combined with a range of external pressures and internal management issues have the potential to derail this important project. To date, stakeholders such as government and business, as well as universities have seriously underestimated the kind of cultural, institutional and policy changes required to implement the graduate skills agenda. This paper outlines the issues that will need to be addressed by the higher education sector if universities are to play a proactive rather than reactive role in shaping this agenda. 相似文献
915.
Sarah Rose Fitzgerald Alexander C. Gardner Marilyn J. Amey Patricia L. Farrell-Cole 《Journal of Higher Education Policy & Management》2018,40(4):359-374
To illuminate barriers to collaboration, this study examines who participates in cross-boundary scholarly collaboration most often and which types of boundary crossing (disciplinary, institutional, role) are engaged in most often. The data of this study came from an interdisciplinary consortium with five partner institutions, including one Historically Black College and University (HBCU). The core disciplines involved in the consortium are life sciences, computer science and math and engineering. Through statistical analysis, we determined that members of the consortium engaged more in interdisciplinary research than inter-institutional research. Participation in all boundary crossing collaborations was greater at the HBCU and students and postdocs were less likely than academics to cross-institutional boundaries. 相似文献
916.
Matthias Pilz Junmin Li Roy Canning Sarah Minty 《Journal of Vocational Education & Training》2018,70(1):1-26
One response to challenges of national vocational training systems has been a move towards greater flexibility within vocational training systems. This article focuses on an investigation of modularisation as a tool for achieving this flexibility. Many European countries have introduced modular forms into their vocational training system. We investigate whether the global trends set out are producing policy convergence in modularisation in differing countries. This study selects seven European countries to make a detailed analysis and entailed an analysis of each country’s Initial Vocational Education and Training programmes. The methodology involved both primary and secondary data collection. The findings demonstrate policy convergence that can be attributed to similar challenges at national level. Modularisation in some countries takes a ‘radical’ form. Other countries have followed a mixed approach. It is clear that no two countries have adopted the same form of modularisation, although some countries have cited common challenges in the modularisation process. 相似文献
917.
Dan Richmond Jim Sibthorp John Gookin Sarah Annarella Stephanie Ferri 《Journal of Adventure Education & Outdoor Learning》2018,18(1):36-52
Recent research underscores the importance of the skills, beliefs and behaviors that support student achievement in the classroom and beyond. This set of intrapersonal and interpersonal assets (e.g. perseverance, grit, social skills, efficacy beliefs and mind-sets) are often referred to as noncognitive factors, as they are not measured directly by traditional academic assessments. Outdoor adventure education (OAE) is well positioned to deliver these desired outcomes—boosting self-confidence, self-efficacy and social skills while developing leadership and communication competencies. Therefore, the primary aim of this study was to better understand the form, function and delivery of an effective OAE program/school partnership targeting factors that support student success. Findings explain how shared OAE experiences among adolescent girls attending the same school contribute to greater social connectedness, self-efficacy in leadership competencies, and a recalibrated sense of self and personal potential. 相似文献
918.
Sarah A. Costigan Nicola D. Ridgers Narelle Eather Ronald C. Plotnikoff Nigel Harris 《Journal of sports sciences》2018,36(10):1087-1094
High Intensity Interval Training (HIIT) may be effective for accumulating VPA. However, the contribution of HIIT to overall physical activity is unknown. Our primary aim was to explore the impact of school-based HIIT on physical activity. The secondary aim was to explore within-individual changes in physical activity after participating in HIIT. Participants [n = 65; 15.8(0.6)years] were randomized to a HIIT or control group. Intervention groups participated in three HIIT sessions/week. GENEActiv accelerometers assessed objective physical activity at baseline and week-one, to detect changes in MPA and VPA. Intervention effects were examined using linear mixed models and evidence of a change in physical activity (i.e., compensation) were examined using multilevel linear regression models. The group-by-time interaction effects for MPA and VPA were small and moderate, respectively. Adjusted difference between groups for VPA was 1.70 min/day, 95%CI –1.96 to 5.36; p = 0.354; d = 0.55). Embedding HIIT within the school-day had a moderate effect on VPA compared to controls. Compensation analyses (i.e., individual level) suggested that adolescents were more active on days when they participated in HIIT. Further studies are needed to test the effects of HIIT on adolescents’ physical activity over extended time periods. 相似文献
919.
Caroline Haythornthwaite Anatoliy Gruzd Sarah Gilbert Marc Esteve del Valle Drew Paulin 《Learning, Media and Technology》2018,43(3):219-235
Learning on and through social media is becoming a cornerstone of lifelong learning, creating places not only for accessing information, but also for finding other self-motivated learners. Such is the case for Reddit, the online news sharing site that is also a forum for asking and answering questions. We studied learning practices found in ‘Ask’ subreddits AskScience, Ask_Politics, AskAcademia, and AskHistorians to develop a coding schema for informal learning. This paper describes the process of evaluating and defining a workable coding schema, one that started with attention to learning processes associated with discourse, exploratory talk, and conversational dialogue, and ended with including norms and practices on Reddit and the support of communities of inquiry. Our ‘learning in the wild’ coding schema contributes a content analysis schema for learning through social media, and an understanding of how knowledge, ideas, and resources are shared in open, online learning forums. 相似文献
920.
Danielle R. Hatchimonji Arielle V. Linsky Sarah DeMarchena Samuel J. Nayman Sarah Kim Maurice J. Elias 《Clearing house (Menasha, Wis.)》2018,91(2):59-65
In response to school environments in which teachers and students feel disconnected from the learning process, we developed a three-part curriculum feedback system with the goal of creating a school-wide culture of engagement through participatory feedback processes. Here we describe the barriers to participation and ownership that are addressed by our curriculum feedback process, provide a rationale for each component of the multi-prong feedback process, and illustrate how each part of the feedback system was implemented in our pilot schools. We argue that addressing feedback regularly, optimizing the process to be user-friendly, and demonstrating appreciation for positive and constructive feedback can help any curriculum supervisor foster a school-wide culture of engagement among teachers and students. 相似文献