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81.
As an introduction to the special issue on “emerging nanotechnologies”, this paper puts in perspective contemporary debates and challenges about nanotechnology. It presents an overview of diverse analyses and expectations about this presumably revolutionary set of technological, scientific and industrial developments. Three main lines of argument can then be delineated: first of all, the degree of cumulativeness of science and technologies and the respective roles of newcomers and incumbents in the industrial dynamics; second the knowledge dynamics in nanotechnologies, especially the linkages by science and technology and third the role of institutions (network, geographic agglomeration and job market). It finally discusses methodologies to delineate the field of nanotechnologies and to collect data.  相似文献   
82.
CONFINTEA VI took place against the background of an uneven and contradictory social and economic impact of globalisation. This impact registered globally and locally, in both the political North and South, drawing new lines of inequality between “core” and “periphery”, between insiders and outsiders of contemporary society. Financial turmoil in the world has exacerbated levels of poverty and insecurity. The question is how work-related education and conceptions of learning might promote greater inclusion and security for those whose livelihoods are most severely affected by globalisation. The Belém Framework for Action implicitly recognises that lifelong learning and work cannot be discussed outside broader socio-economic and political contexts. The authors of this article draw substantially on research from around the world and argue for the re-insertion of “politics and power” into both the theory and practice of “lifelong learning” and “work”.  相似文献   
83.
The most successful school library media specialists are those who collaborate with teachers as full partners in the instructional process. Without assertive action by the school library media specialist, however, school administrators and teachers are likely to be more aware of the media specialist’s administrative role than the roles of teacher, instructional partner, and information specialist. Reductions to library media staff and finding common planning time are examples of serious challenges, but these are not insurmountable. In the context of well-planned instructional projects, collaboration with teachers is a primary way that school library media professionals can demonstrate that their work is a vital part of the academic life of their schools, and a positive factor in improving student achievement.  相似文献   
84.
The aim of this study was to determine the influence of punch type (Jab, Cross, Lead Hook and Reverse Hook) and punch modality (Single maximal, 'In-synch' and 'Out of synch' combination) on punch speed and delivery time. Ten competition-standard volunteers performed punches with markers placed on their anatomical landmarks for 3D motion capture with an eight-camera optoelectronic system. Speed and duration between key moments were computed. There were significant differences in contact speed between punch types (F(2,18,84.87) = 105.76, p = 0.001) with Lead and Reverse Hooks developing greater speed than Jab and Cross. There were significant differences in contact speed between punch modalities (F(2,64,102.87) = 23.52, p = 0.001) with the Single maximal (M+/- SD: 9.26 +/- 2.09 m/s) higher than 'Out of synch' (7.49 +/- 2.32 m/s), 'In-synch' left (8.01 +/- 2.35 m/s) or right lead (7.97 +/- 2.53 m/s). Delivery times were significantly lower for Jab and Cross than Hook. Times were significantly lower 'In-synch' than a Single maximal or 'Out of synch' combination mode. It is concluded that a defender may have more evasion-time than previously reported. This research could be of use to performers and coaches when considering training preparations.  相似文献   
85.
86.
Separation and sorting of biological entities (viruses, bacteria, and cells) is a critical step in any microfluidic lab-on-a-chip device. Acoustofluidics platforms have demonstrated their ability to use physical characteristics of cells to perform label-free separation. Bandpass-type sorting methods of medium-sized entities from a mixture have been presented using acoustic techniques; however, they require multiple transducers, lack support for various target populations, can be sensitive to flow variations, or have not been verified for continuous flow sorting of biological cells. To our knowledge, this paper presents the first acoustic bandpass method that overcomes all these limitations and presents an inherently reconfigurable technique with a single transducer pair for stable continuous flow sorting of blood cells. The sorting method is first demonstrated for polystyrene particles of sizes 6, 10, and 14.5 μm in diameter with measured purity and efficiency coefficients above 75 ± 6% and 85 ± 9%, respectively. The sorting strategy was further validated in the separation of red blood cells from white blood cells and 1 μm polystyrene particles with 78 ± 8% efficiency and 74 ± 6% purity, respectively, at a flow rate of at least 1 μl/min, enabling to process finger prick blood samples within minutes.  相似文献   
87.
Early Childhood Education Journal - Young children’s ideas of fairness have been studied in a range of laboratory settings with findings that children see fairness as equal distribution of...  相似文献   
88.
89.
Relative to print reading, braille-reading finger movements are held to be of more constant speed, with continuous and exhaustive contact with all words. However, the continuity of movements is intermittent in two distinct ways: (a) readers reverse direction and reread material already encountered and (b) the continual fluctuations of velocity between phases of acceleration and deceleration. We analyze recordings of experienced readers’ encounters with ambiguous sentences predicted to encourage more reversals, and we undertake comparative kinematic analyses of the finger movements during such reading. The data suggest that when reversals are initiated and where they are targeted reflect language-processing demands. However, their kinematic properties are not qualitatively different from those of forward reading. We conclude that how readers of braille move the reading finger—both forward and in reverse—is primarily influenced by the control properties of low-velocity movements and only secondarily by language properties.  相似文献   
90.
This article reports an investigation into how students of a mathematics course for prospective secondary mathematics teachers in England talk about the notion of ‘understanding mathematics in depth’, which was an explicit goal of the course. We interviewed eighteen students of the course. Through our social practice frame and in the light of a review of the literature on mathematical knowledge for teaching, we describe three themes that weave through the students’ talk: reasoning, connectedness and being mathematical. We argue that these themes illuminate privileged messages in the course, as well as the boundary and relationship between mathematical and pedagogic content knowledge in secondary mathematics teacher education practice.  相似文献   
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