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Archaeological fish bones reveal increases in marine fish utilisation in Northern and Western Europe beginning in the 10th and 11th centuries AD. We use stable isotope signatures from 300 archaeological cod (Gadus morhua) bones to determine whether this sea fishing revolution resulted from increased local fishing or the introduction of preserved fish transported from distant waters such as Arctic Norway, Iceland and/or the Northern Isles of Scotland (Orkney and Shetland). Results from 12 settlements in England and Flanders (Belgium) indicate that catches were initially local. Between the 9th and 12th centuries most bones represented fish from the southern North Sea. Conversely, by the 13th to 14th centuries demand was increasingly met through long distance transport – signalling the onset of the globalisation of commercial fisheries and suggesting that cities such as London quickly outgrew the capacity of local fish supplies.  相似文献   
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Changes in the exploitation of resources among prehistoric hunter-gatherer-fishers of the Beagle Channel (Southern South America) are examined in this paper. Archaeological investigations show the prevalence of maritime hunter-gatherer organization throughout the occupation of the region (ca. 6400 BP – 19th century). Notwithstanding, variations in the exploitation of different kind of animal resources have been detected, and a concomitant reorientation in the landscape use is then inferred. Zooarchaeological evidence from five shellmiddens is analyzed here: evenness measures and relative abundance prey types are used to evaluate such adjustments. Results indicate the major utilization of coastal and terrestrial ecozones and the predominance in the exploitation of mammals (pinnipeds and guanacos) in ancient occupations. While, during the Late Holocene an expansion in ranges of maritime mobility for subsistence is detected, which was associated with an increase in the representation of birds and fish in the zooarchaeological record.  相似文献   
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Over the last half century, scientists and engineers have developed methods to better understand and mitigate the damage caused by tsunamis. According to U.S. Federal Emergency Management Agency (FEMA) P646, buildings in many regions, including the U.S. Pacific Northwest, will experience substantial ground shaking from an offshore earthquake that precedes a tsunami and then experience the tsunami forces themselves. Thus, both hazards should be considered in computing the damage and collapse risk to buildings. This article summarizes a basic approach to numerically consider the successive seismic and tsunami risk to buildings in near-field tsunami regions such as the U.S. Pacific Northwest.  相似文献   
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al-Tikha is a mid to large Umm an-Nar (c. 2700–2000 BC) settlement situated near Rustaq at the back of the Southern Batinah coastal plain in the Sultanate of Oman that was discovered (or rediscovered) in 2014. The site is unique because its layout and spatial organisation are very largely (possibly completely) visible on the surface. This includes two separate areas of stone-built housing, a large pottery scatter of varying density, three or four typical Umm an-Nar round towers and a small cemetery consisting of at least four tombs, along with a few other features. The layout of the site is described and discussed in detail, in particular, in relation to what it might tell us about the nature of Umm an-Nar settlement and social organisation more generally. The location of the site within a pattern of repeating Umm an-Nar settlement along Wadi Far (Wādī al-Farʿī) is also described and discussed.  相似文献   
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Just when molecular biology is arguably delivering on some of its long-promised medical applications—think mRNA vaccines, monoclonal antibody drugs, PCR testing, and gene therapies—the history of molecular biology has lost much of its shine. What not too long ago seemed like a burgeoning field of research with endless possibilities, is now often reduced to the “central dogma” that saw its apotheosis in the effort to sequence the human genome but has since unraveled. The essay will discuss several possible answers to this apparent paradox.  相似文献   
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The purpose of this paper is to spatially and regionally examine academic engagement within Brazil, identifying patterns. Moreover, our investigation can contribute to a better understanding of how knowledge can be turned into a tool to fight regional inequality. We depart from two hypotheses: first, universities situated in peripheral regions interact more with companies from relatively more dynamic regions, and second, in the absence of industrial knowledge demand, universities tend to collaborate more closely with a diverse range of stakeholders in the region. To evaluate these hypotheses and find empirical evidence, we consider 4497 research groups and 4603 nonacademic organizations as “nodes” connected by 8830 collaborations throughout all Brazilian regions. Social network tools are used to illustrate the spatial and regional dimensions of academic engagement more accurately. The results show that academic engagement is not regionally homogeneous, demonstrating essential differences regarding local nonacademic partnerships. Innovation policies, which encourage only university–firm interactions, perpetuate regional inequality.  相似文献   
110.
A European Directive stipulates that at least 10% of programmes broadcast by each European broadcaster must be produced by an independent producer. By stimulating independent productions the European Union and the Dutch government aim to improve the quality of television programmes. In 1997, the Netherlands increased this requirement to 25%. This paper evaluates the policy, using a unique Dutch dataset that includes all independent productions appearing on public television from 1996 until 2000. We show that: (i) the producers are highly specialised; (ii) programming is volatile; (iii) entry of new firms is substantially reducing average rates of turnover; (iv) the producers who lobbied for the higher quota were losing market share and were relatively well‐organised. Therefore, the outsourcing requirement does not lead to the desired levels of stable production by individual producers and it is unlikely to be an effective instrument.  相似文献   
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