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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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The palaeobiota from a middle to late Holocene succession in Tom Thumbs Lagoon, N.S.W., Australia, reflects a range of environmental conditions caused by sea-level changes and active estuarine sedimentation. At the base of the succession (~ ?0.4 m AHD) a thin bed, containing molluscs dated at 6.7 ka B.P. by radiocarbon and amino acid racemisation, and foraminifers is indicative of open estuarine conditions. From +0.35 m AHD towards the top of the sequence the charophyte Lamprothamnium succinctum occurs in subrecent deposits. This species is characterised here by statistical measurements, and new characters are described and illustrated. The charophytes record a drop in sea level and the establishment of a lower salinity artificial wetland. The investigation has also established that decalcification in charophytes can be related to acidification produced by the release of organic acids, aggravated after 1928 by anthropogenic pollution.  相似文献   
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