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21.
In this paper, we explore regional innovation in the use of varieties of algae as inputs to industrial processes. It is important to understand that algae are one of nature's most bountiful products, with an almost infinite variety of applications. Algae have received prominence in the research literature because of the strong evidence that they can make a major contribution to the production and—importantly—storage of renewable energy. Following the introduction to this paper, Section 2 reviews the nature and application of algae in two main aspects of clean energy production: first as biogasolene or biodiesel; second as large-scale storage batteries for electricity. The latter is particularly important as one classic deficiency of electricity is the difficulty in storing it for lengthy periods other than in short-life batteries. However (Section 3), there are other uses for algae, ranging from aquaculture to medicine and the production of cosmetics. In the southwest corner of the Iberian Peninsula, between Faro in Portugal through Huelva to Cadiz in Spain, is a significant research and commercial algae production zone. The paper describes the key system elements in play in this trans-border innovation network and considers prospects for new path creation towards biofuels, the main research and application centres for which are in the San Francisco Bay Area in California. Conclusions and recommendations for policy action are then drawn. 相似文献
22.
Ruth Dickau Stewart D. Redwood Richard G. Cooke 《Archaeological and Anthropological Sciences》2013,5(4):331-349
During new excavations at the preceramic rockshelter of Casita de Piedra in western Panama, a cache of 12 unusual stones was recovered near the back wall, dating to between 4800 and 4000 cal bp. The stones include quartz, pyrite, a chalcedony vein nodule, a bladed quartz and jarosite aggregate and a human-modified dacite cylinder. Based on the unusual lithic types and the context of the cache, we suggest that these stones once belonged to a ritual specialist, such as a healer or shaman. Special stones are frequently mentioned as being an important component of a shaman’s ritual paraphernalia in ethnographic records of various historic Native American groups throughout Central and South America, including the Bribri and Cabécar of southeastern Costa Rica and western Panama (formerly known as the ‘Talamanca’). The cache of stones recovered at Casita de Piedra may represent the earliest material evidence in Central America of shamanistic practice. 相似文献
23.
The Scottish Executive has adopted a policy to combat Scotland's declining population by encouraging inward migration. Using a multi‐state population model this paper presents nine long‐term population scenarios for Scotland using three net international migration levels and three fertility paths. The results show inward migration can slow population decline but makes little difference to population ageing. Without a higher fertility rate Scotland's population will become demographically unsustainable. Our simulations show that a higher fertility rate substantially reduces the future ageing. 相似文献
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