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11.
Collaboration between practitioners and researchers can increasingly be observed in research and development (R&D) projects in secondary schools. This article presents an analysis of cross-professional collaboration between teachers, school leaders and educational researchers and/or advisers as part of R&D projects in terms of three dimensions: reasons for collaboration, the division of roles and tasks, and the communication structure. Data were collected in interviews with participants from 12 Dutch projects, from documents and from meetings with participants. The results show that the parties involved can have the same reasons for cross-professional collaboration but that the external educational experts may also have additional objectives. Roles and tasks were divided in different ways, depending on who directs and guides the research and development, and whether teachers were involved as teacher researchers in the project. The communication structure appeared to be linked to the division of roles and tasks, but also to the number of participants in the project. The three dimensions proved to be valuable viewpoints to study cross-professional collaboration in R&D projects in Dutch secondary education. Furthermore, we distinguished four types of cross-professional collaboration in R&D projects. These types differ in the extent to which the school or the external party direct and guide the project: (a) School-directed collaboration; (b) School- and researcher-directed collaboration; (c) School- and adviser-directed collaboration; (d) Researcher-directed collaboration. Our findings can support participants to consciously choose a particular type of cross-professional collaboration that fits their purposes and specific situation.  相似文献   
12.
Models are very important tools when learning and communicating about science. Models used in secondary school biology education range from concrete scale models, such as a model of a skeleton, to abstract concept-process models, such as a visualisation of meiosis. Understanding these concept-process models requires a profound understanding of the concept of models and how they are used in biology. This study evaluates an existing framework for its use in assessing students’ understanding of biological concept-process models. Four additions were required to extend the applicability of the framework to concept-process models. We were also able to give an indication of students’ current level of understanding of these models, showing room for improvement in all aspects of understanding. Since concept-process models have a central place in many scientific disciplines, it is important that students have a deep understanding of the nature, application and limitations of these models. The current study contributes to assessing the way students reason with concept-process models. Knowing how to improve students’ view on the use of concept-process models in biology may lead to higher scientific literacy.  相似文献   
13.
Small-sided games (SSGs) are used in training sessions to prepare for full-sized matches. For the same number of players, smaller pitch sizes result in decreased physical performance and shorter interpersonal distances. A relative pitch area derived from the full-sized match results in larger pitch sizes and this may increase the fit between SSGs and full-sized matches. This study aimed to investigate SSGs with a traditional small pitch and a match-derived relative pitch area in youth elite soccer players. Four age categories (under-13, under-15, under-17 and under-19) played 4 vs. 4 plus goalkeepers on a small (40x30m, 120m2 relative pitch area) and large pitch (68x47m, 320m2 relative pitch area). The number of games per age category ranged 15–30. Positional data (LPM-system) were collected to determine physical (total distance covered, high intensity distance and number of sprints) and team tactical (inter-team distance, LPW-ratio, surface area, stretch indices, goalkeeper-defender distance) performance measures and tactical variability. On a large pitch, physical performance significantly increased, inter-team and intra-team distances were significantly larger and tactical variability of intra-team distance measures significantly increased. The match-derived relative pitch area is an important training manipulation and leads to changes in physical and tactical performance 4 vs. 4 plus goalkeepers.  相似文献   
14.
It is commonly understood that teachers in secondary school should develop throughout their career in order to stay as an essential factor in student learning. Schools can offer opportunities to link teachers’ professional learning to their school practice with a positive impact on teachers’ motivation to learn and the effectiveness of their learning. In this field study, teachers, school leaders, policy-makers, educational consultants and educational scholars were asked for their perceptions of conditions for teacher learning in school and of interventions in school to enhance teacher professional learning. These conditions and interventions were understood as affordances in schools that enable and support teacher professional learning. The main affordance in school these stakeholders mentioned was an open, but critical way in which teachers share their practices, collaborate and reflect upon their teaching practice. Collaborative practices seem to stimulate many interventions of teacher professional learning in school. Two implications of this finding are discussed. First, we suggest that the maximum teaching time should be reduced, team teaching should be more implemented or classes should be scheduled in such a way that teachers can meet. Second, distributed leadership approaches match with our findings about the role of school leaders in teacher professional learning.  相似文献   
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Wouter Stam   《Research Policy》2009,38(8):1288-1299
This study examined how participation in open innovation communities influences the innovative and financial performance of firms commercializing open source software. Using an original dataset of open source companies in the Netherlands, I found that the community participation–performance relationship is curvilinear. In addition, results indicate that extensive technical participation in open source projects is more strongly related to performance for firms that also engage in social (“offline”) community activities, for companies of larger size, and for firms with high R&D intensities. Overall, this research refines our understanding of the boundary conditions under which engagement in community-based innovation yields private returns to commercial actors.  相似文献   
17.
Vitamin B12 deficiency can present with neurologic and psychiatric symptoms without macrocytic anaemia. We describe a case of late-onset cobalamin C deficiency which typically presents with normal serum vitamin B12 concentrations, posing an additional diagnostic challenge. A 23-year-old woman with decreased muscle strength and hallucinations was diagnosed with ‘catatonic depression’ and admitted to a residential mental health facility. She was referred to our hospital for further investigation 3 months later. Heteroanamnesis revealed that the symptoms had been evolving progressively over several months. Magnetic resonance imaging (MRI) of the brain showed diffuse symmetrical white matter lesions in both hemispheres. Routine laboratory tests including vitamin B12 and folic acid were normal except for a slight normocytic, normochromic anaemia. Over the next 6 weeks her symptoms deteriorated, and she became unresponsive to stimuli. A new MRI scan showed progression of the white matter lesions. The neurologist requested plasma homocysteine (Hcys) which was more than 8 times the upper limit of normal. Further testing revealed increased methylmalonic acid and the patient was diagnosed with adult-onset cobalamin C deficiency. This case illustrates that Hcys and/or methylmalonic acid should be determined in patients presenting with neuropsychiatric symptoms suggestive of vitamin B12 deficiency with a normal serum vitamin B12 to rule out a late-onset cobalamin C deficiency.  相似文献   
18.
Many countries spend sizeable sums of public money on R&D grants to alleviate debt and equity gaps for small firms’ innovation projects. In making such awards, knowledgeable government officials may certify firms to private financiers. Using a unique Belgian dataset of 1107 approved requests and a control group of denied requests for a specific type of R&D grant, we examine the impact of subsidies on small firms’ access to external equity, short term and long term debt financing. We find that obtaining an R&D subsidy provides a positive signal about SME quality and results in better access to long-term debt.  相似文献   
19.
GearSketch is a learning environment for the gears domain, aimed at students in the final years of primary school. It is designed for use with a touchscreen device and is based on ideas from drawing-based learning and research on cognitive tutors. At the heart of GearSketch is a domain model that is used to transform learners’ strokes into gears and chains, animate the turning of the gears and check whether learners’ solutions to practice problems satisfy the given constraints. Additionally, this domain model is the basis for GearSketch’s learner model and item generation an selection mechanisms. The learner model is used to track learners’ knowledge and adaptively select items as they progress through the practice problems. Two experimental evaluation studies show that GearSketch’s interface and animations lead to improved learning outcomes, but that its adaptive features do not significantly affect posttest results.  相似文献   
20.
Genetic sequence and hyper-methylation profile information from the promoter regions of tumor suppressor genes are important for cancer disease investigation. Since hyper-methylated DNA (hm-DNA) is typically present in ultra-low concentrations in biological samples, such as stool, urine, and saliva, sample enrichment and amplification is typically required before detection. We present a rapid microfluidic solid phase extraction (μSPE) system for the capture and elution of low concentrations of hm-DNA (≤1 ng ml−1), based on a protein-DNA capture surface, into small volumes using a passive microfluidic lab-on-a-chip platform. All assay steps have been qualitatively characterized using a real-time surface plasmon resonance (SPR) biosensor, and quantitatively characterized using fluorescence spectroscopy. The hm-DNA capture/elution process requires less than 5 min with an efficiency of 71% using a 25 μl elution volume and 92% efficiency using a 100 μl elution volume.  相似文献   
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