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排序方式: 共有773条查询结果,搜索用时 15 毫秒
71.
Abstract

Purpose: The study investigated to what extent local farmers' organisations are spaces where farmers discuss, learn and innovate.

Design/methodology/approach: Two milk collection cooperatives in Morocco were studied. The study analysed the discussion networks, their impacts on farmers' knowledge and innovation, and the performance of collective action at cooperative level.

Findings: In both cooperatives, only two-thirds of the farmers regularly discussed dairy practices with other farmers. Most leaders of one cooperative were acknowledged to be experienced farmers and played key roles as advisors on dairy farming. Farmers' involvement in dialogue networks in this cooperative improved their capacity to innovate in dairy farming, even though their knowledge on some issues related to cattle, health and nutrition was not improved. In the other cooperative, experienced farmers did not share their knowledge and farmers' involvement in dialogue networks at cooperative level had no impact on their knowledge and practices. Dialogue networks and collective action were found to influence each other, since in the first cooperative, collective action was considered by members to be efficient, whereas in the second collective action was limited to milk collection.

Practical implications: The study enabled identification of stumbling blocks which need to be addressed to get local farmers’ organisations involved in farmer capacity-building.

Originality/value: While the importance of local discussion networks for knowledge creation and diffusion is widely acknowledged, taking such networks into account in farmers' capacity-building programmes in developing countries has been hindered by their informality. Combining the analysis of dialogue networks and collective action proved to be a productive way to assess the potentialities of working with farmers' organisations with the aim of establishing a connection with local discussion networks.  相似文献   
72.
As part of a working definition of a new code of practice, this paper develops a methodology to determine the suitability of plasters manufactured on-site to protect the earthen walls of vernacular architecture buildings. Given the diversity of raw earth construction types, ranging from massive earth to stone masonry with earth mortars, and the variability of the materials used, two on-site tests (a shrinkage test followed by a shear test) were proposed. Those tests, as well as additional tests, were performed with lime/sand, earth/sand and earth with plaster admixtures. Lime/sand plasters do not typically pose shrinkage issues, which is why more earth based specimens were tested than lime based specimens. An analysis of the on-site testing complemented with laboratory tests reveals an antagonistic control of the bond between earth plaster and earthen wall based on clay content: an increase in the plaster clay content leads to increased bending strength, which strengthens the plaster and increased shrinkage, which weakens the plaster-wall interface. The heterogeneity of the wall leads to a wide range of results; therefore, this study was conducted to validate the formulation of plasters by means of shrinkage and shear tests at five different points on the wall. The shrinkage test allows finding the earth plaster formulations. Among all the validated formulations, the mason chooses the best one thanks to two criteria: the best workability (which is variable according to masons) with the highest clay content as possible. Then, when the formulation is chosen, the shear test must be done to verify if the bond between the plaster and the wall is high enough. This series of tests allows masons to validate formulations that will ensure good mechanical resistance of the plasters that protect buildings of vernacular earthen architecture.  相似文献   
73.
Integrating knowledge across a firm's value chain (e.g. between R&D, marketing and manufacturing functions), which we denote “Knowledge Integration” (KI), has been consistently found to be a strong predictor of product innovation performance in the management literature. Such cross-functional integration does not occur by chance, but by design, as a result of managerial practices and organizational arrangements. The significant heterogeneity characterizing the diffusion of cross-functional integration across firms is suggestive of the well-known tension between internal and external diffusion of knowledge. In this paper, we argue that the hidden cost of KI is to expose firms to a higher risk of knowledge leakages and provide the first systematic empirical evidence of this apparent tension between internal and external knowledge flows. Based on data from the CMU Survey (one of the rare datasets offering observables on both sides of the tension for a representative set of R&D active firms in the US), we investigate the impact of knowledge spillovers to competitors on internal cross-functional knowledge integration involving the R&D function among manufacturing firms. We find that the intensity of (tacit) R&D knowledge spillovers at the industry-level has a negative and significant impact on the likelihood that firms adopt or achieve KI. Our results therefore suggest that firms may trade their optimal innovative performance against superior appropriability of their rents.  相似文献   
74.
Task selection and task execution are key constructs in cognitive control development. Yet, little is known about how separable they are and how each contributes to task switching performance. Here, 60 4- to 5-year olds, 60 7- to 8-year olds, and 60 10- to 11-year olds children completed the double registration procedure, which dissociates these two processes. Task selection yielded both mixing and switch costs, especially in younger children, and task execution mostly yielded switch costs at all ages, suggesting that task selection is costlier than task execution. Moreover, both task selection and execution varied with task self-directedness (i.e., to what extent the task is driven by external aids) demands. Whereas task selection and task execution are dissociated regarding performance costs, they nevertheless both contribute to self-directed control.  相似文献   
75.
A double-blind randomized controlled trial of n-3 long-chain polyunsaturated fatty acid (n-3 LCPUFA) supplementation or matching placebo during third trimester of pregnancy was conducted within the COPSAC2010 mother-child cohort consisting of 736 women and their children. The objective was to determine if maternal n-3 LCPUFA pregnancy supplementation affects offspring neurodevelopment until 6 years. Neurodevelopment was evaluated in 654 children assessing age of motor milestone achievement, language development, cognitive development, general neurodevelopment, and emotional and behavioral problems. Maternal n-3 LCPUFA supplementation during pregnancy improved early language development and reduced the impact of emotional and behavioral problems. The n-3 LCPUFA supplementation was in boys associated with the earlier achievement of gross motor milestones, improved cognitive development, and a reduced impact of emotional and behavioral problems.  相似文献   
76.
Neoliberalism has become a highly dominating and taken-for-granted way of organising the university sector around the world. In the critical educational literature, this market-based rationality has been scrutinised in detail over the past decades. However, rather scant attention has been directed to how university managers and administrators, apart from setting up quasi-markets, may intervene more directly to give the invisible hand of the market a helping hand. Aiming to address this lacuna, the purpose of the current article is to develop an empirically grounded taxonomy of different types of such interventions, and to theorise them in terms of the different facets of the neoliberal milieu that they reproduce and the various forms of subjectivising work among academics that they seek to engender. We do so by means of a qualitative study of so-called ‘Grants Offices’ at three Swedish universities. The findings arguably add to and problematise our understanding of how neoliberal markets work in academia in three different ways. First, while extant research has noted that university managers and administrators may intervene beyond the setting up of neoliberal markets per se, our study is to our knowledge the first one that identifies and systematises a broad array of such interventions. Second, it problematises the view of neoliberal markets as a form of monolithic entity that produces a uniform competitive pressure on academics. Third, and related, it furthers our understanding of the type of subjectivity that competitive milieus are assumed to bring about.  相似文献   
77.
Corni  Federico  Fuchs  Hans U. 《Interchange》2021,52(2):203-236
Interchange - This is the second of two papers on a novel physical science course for student teachers that develops and uses an imaginative approach to Primary Physical Science Education....  相似文献   
78.
当今时代,人类差不多生活在数字的漩涡里。数学在时空实在中的可应用性问题,本质上是一个知识论的问题,文章分四个步骤对该问题进行了剖析:先是讨论亚里士多德的数学作为一种抽象的观点,随之讨论柏拉图的数学理念论,继之讨论康德的构造主义纲领,最后讨论维特根斯坦的规则理论。文中作者试图将康德与维特根斯坦的观点结合起来,以发展出一种“规则主义”,从而突破构造主义的限制,为古典数学留块地盘。在文章的最后,作者还指出了数学化的限度。  相似文献   
79.
The purpose of this study was to discover whether there are scholarly evaluation metrics that can be applied to a wide range of books’ types and contents. We analyzed over 70,000 books and collected various metrics per each title including traditional and altmetrics measures. The analysis in this paper depicts the top books showing the highest rates of citations, reviews, readership, downloads, twitter and more. Our results show that books display different impact in each of the measurements and vary by types and content. There isn’t one measure that captures the impact of books across the board. We conclude that books should be evaluated by types and contents while using different measures per each.  相似文献   
80.
It is under debate whether the neural representation of numbers and letters might rely on distinct neural correlates, or on a mostly shared neural network. In the present study, a total of 47 children in fifth grade (Experiment 1) and sixth grade (Experiment 2) simply copied numbers and letters on a touch screen while brain activation changes were recorded by means of functional near‐infrared spectroscopy (fNIRS). fNIRS data of both experiments and a joint analysis revealed that a shared neural network, particularly in the left hemisphere, was activated in response to both number and letter copying. Interestingly, no difference was observed in brain activation patterns between these two stimuli, as revealed by Bayesian analysis. Our findings indicate that both number and letter copying lead to similar brain activation in children. We further suggest methodological and applied applications of these findings in the frame of educational neuroscience.  相似文献   
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