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951.
Goodson  Ivor F.  Schostak  John F. 《Prospects》2021,51(1-3):29-45

The coronavirus crisis has appeared like some vast, cruel sociological experiment. It has confined people to their homes, radically disturbed their taken-for-granted knowledge and beliefs, and forced them to alter behaviors once casually, even unthinkingly, employed in their everyday personal, working, and social lives. What has been learned? How might this experience stimulate a reimagining of the curriculum? More fundamentally, how might it lead to the development of a knowledgeable, intelligent, effective public, able to engage freely and equally in decision-making at all levels of social, cultural, political, and economic life, as a condition for personal freedom? This article explores the implications of “lockdown” or “confinement” to homes, which has suspended freedom of movement, limited the freedom to associate with others, and established rituals of hygiene regarding surfaces. These experiences of physical confinement and limitation of ordinary freedoms raise the central question of how to return to “normal” and, indeed, what will count as normal. In exploring the issues posed by these questions, this article offers an approach to pedagogical and curriculum practice that seeks to embed democratic practice at all levels of organization and interaction between individuals.

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The need for collaborative ventures in Europe has long been stressed in the editorial pages of this journal, and more than ten years ago (Endeavour, 28, 54, 1969) we gave strong support for a proposal to establish a European Laboratory of Molecular Biology. For this we then incurred some criticism, on the ground that such a laboratory would weaken national academic institutes striving to establish themselves in this rapidly developing field. Nevertheless, we continued to maintain (30, 2, '71) ‘the great political and scientific importance of this [concept]—and of other such collaborative enterprises—if Europe is to maintain the initiative in fields where the great institutions of the United States have established a dominant position.’ In the event, the Laboratory was established at Heidelberg in 1974, though not formally opened until 1978. The Director-General, Sir John Kendrew, here surveys the policy and achievements of this important new institute.  相似文献   
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The evidence from randomized controlled trials (RCTs) is widelyregarded as supplying the ‘gold standard’ in medicine—wemay sometimes have to settle for other forms of evidence, butthis is always epistemically second-best. But how well justifiedis the epistemic claim about the superiority of RCTs? This paperadds to my earlier (predominantly negative) analyses of theclaims produced in favour of the idea that randomization playsa uniquely privileged epistemic role, by closely inspectingthree related arguments from leading contributors to the burgeoningfield of probabilistic causality—Papineau, Cartwrightand Pearl. It concludes that none of these further argumentssupplies any practical reason for thinking of randomizationas having unique epistemic power.
1 Introduction
2 Why theissue is of great practical importance—the ECMOcase
3Papineau on the ‘virtues of randomization’
4 Cartwrighton causality and the ‘ideal’ randomizedexperiment
5 Pearl on randomization, nets and causes
6 Conclusion
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Two different bond-graph schemes for the modeling of circulating fluids are discussed and compared. The first uses a heuristic approach wherein the flow path is broken into segments. Each segment has separate hydraulic and thermal submodels which are linked with active bonds. The model is general enough to handle natural convective flows, heat storage, conduction, forced convective heat transfer and heat energy sources. The second method, applicable to pumped flows, uses a modal analysis approach to derive state equations for the modal temperatures, the time varying coefficients of the spatially varying mode shapes in a separation of variables solution for the temperature partial differential equation. Two examples are worked to illustrate the models. Numerical simulation results are presented using the first method and a simple analytic solution given to illustrate the second.  相似文献   
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本文对秦始皇兵马俑博物馆室内采集的长短期降尘、大气悬浮颗粒物和彩绘漆层进行了SEM-EDX研究,在大气悬浮颗粒、短期和长期降尘中,含硫颗粒的粒径分别为0.9~22.8μm、1.0~29.0μm和1.2~37.7μm,多为石膏与粘土或石英以内部混合的状态存在。降尘中的附着型絮状硫酸钙多于大气悬浮颗粒物中,显示降尘和大气中的二氧化硫发生了累进的化学反应。彩绘漆层表面的坑和裂隙附近观察到原位生长的硫酸钙晶体,显示漆层材料或降尘颗粒物与大气二氧化硫之间的酸化学反应,可能是彩绘漆层表面受侵蚀形成微小坑和裂隙的原因之一。  相似文献   
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Communities with high levels of social capital are likely to have a higher quality of life than communities with low social capital. This is due to the greater ability of such communities to organize and mobilize effectively for collective action because they have high levels of social trust, dense social networks, and well-established norms of mutuality (the major features of social capital). Communities with “bridging” social capital (weak ties across groups) as well as “bonding” social capital (strong ties within groups) are the most effective in organizing for collective action. People who belong to multiple groups act as bridging ties. When people with bridging ties use communication media, such as the Internet, they enhance their capability to educate community members and to organize, as needed, for collective action. This article summarizes evidence from stratified household survey data in Blacksburg, VA, showing that people with weak (bridging) ties across groups have higher levels of community involvement, civic interest, and collective efficacy than people without bridging ties among groups. Moreover, heavy Internet users with bridging ties have higher social engagement, use the Internet for social purposes, and have been attending more local meetings and events since going online than heavy Internet users with no bridging ties. These findings may suggest that the Internet—in the hands of bridging individuals-is a tool for enhancing social relations and information exchange, and for increasing face-to-face interaction, all of which help to build both bonding and bridging social capital in communities.  相似文献   
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