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In the great civilisations of the past, shapeshifting promised a restoration of order in turbulent times in return for the deference of loyal subjects. It was a strategy of the powerful to maintain advantage and could also be used to bind opponents to an undesired form. This study finds its resonance in the contemporary shapeshifting that is the supposed transition from the fossil fuel economy. With reference to the fusion of oil, grain and sugar companies in Brazil's ethanol sector, it explores how amidst economic, environmental and political insecurity these “old villains” of the carbon economy have fused and emerged as the “new heroes” of the green economy. Accounts of dissenting rural subjects, however, unveil the mythical nature of avowed social gains from this shapeshifting. Amidst rural conflict and a successive weakening of regulation, it becomes evident how their petrification, in a metaphorical and increasingly literal sense is required.  相似文献   
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The urban archaeological site of Nicopolis ad Istrum in north central Bulgaria, which has multiple periods of use and abandonment, has produced a large and varied ichthyofauna. A number of bones of the European catfish Siluris glanis have been identified and have been interpreted as both food remains and bone artifacts. It was found that a percentage bias in the distribution of S. glanis bones from the Roman period of occupation called for further analysis. The investigation attempts to identify the reason or reasons for the apparent overrepresentation of the pectoral fin spines of this species. Taphonomic factors are considered along with butchery and an actualistic study of butchery on modern S. glanis material. Studies from north Africa are used to illustrate the possible function of the spines. The conclusions drawn are that a high proportion of the pectoral fin spines were brought into the site, possibly as personal artifacts. Their use is open to debate; no clear functional use can be determined from the archaeological material, although it cannot be ruled out that they were used for medicinal purposes or as charms.  相似文献   
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Active learning is increasingly promoted within institutions of higher education to assist students develop higher order thinking and link knowledge to meaning. In this paper, the authors evaluate the use of weekly online quizzes based on prescribed preparatory material as a tool to incentivize preparatory reading in order to enable and encourage active learning. The study is based on mixed data sources, including three years of student-evaluation data, to understand student perceptions of the role and value of online quizzes. The study shows a high level of student engagement with the quizzes and positive assessment of their role in encouraging the completion of prescribed reading. Online quizzes were found to be an effective mechanism for incentivizing student completion of preparatory work, enhancing active learning (such as through in-class discussions), and were relatively time efficient from the perspective of the educator.  相似文献   
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Abstract

Recombinant DNA technology was invented in 1973. Within a few years, molecular biologists began developing practical applications and establishing private companies to exploit them commercially. In 1978, Harvard biologist Walter Gilbert, one of the leading figures in the field, joined the founding scientific advisory board of a Swiss biotech startup called Biogen. He later became the company’s CEO. His participation helped Biogen recruit top scientific talent in the United States and Europe and encouraged many of his professional colleagues to follow his example and go into business. In this way, Gilbert became a linchpin in the formation of the contemporary biotechnology industry. Because his adventures in business were shaped by circumstances unique to the late twentieth century, Gilbert’s case adds a distinctive point of reference to studies of academic entrepreneurship. It also points to internal contradictions and conceptual ambiguities in neo-institutional accounts of research privatization.  相似文献   
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