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91.
Excavations in 1970, 1996, and 1999 at Site QJ-280, Quebrada Jaguay, in southern Peru, yielded enough dateable terrestrial plant material to establish an extensive radiocarbon chronology for the site. QJ-280 is one of oldest well-dated fishing sites in the Americas: it was occupied from the terminal Pleistocene to the mid-Holocene (about 13,000–8,300 calibrated years BP) based on 42 terrestrial radiocarbon dates, encompassing the Jaguay and Machas Phases of the local archaeological sequence. In addition to the terrestrial dates, radiocarbon measurements on valves of two marine surf clam (Mesodesma donacium) individuals from a single, well-dated mid-Holocene Manos Phase archaeological context have provided insight into marine upwelling conditions during the occupation of Quebrada Jaguay. The marine reservoir age varied between 130 and 730 14C years during the brief lives of the two clams (up to 5 years each), and varied by up to 530 14C years within an individual valve, suggesting strong and variable deep marine upwelling; conditions broadly similar to those that exist in coastal Peru today. These rapid variations in marine radiocarbon age suggest that marine radiocarbon dates from environments with variable upwelling could be skewed by up to hundreds of years.  相似文献   
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Controlled rocking heavy timber walls are designed to rock on their foundations in response to earthquakes. For regions of moderate seismicity, it is proposed that this rocking behaviour can be adequately controlled using only post-tensioning, even with a large force-reduction factor and no supplemental energy dissipation. This article presents a force-based design procedure for controlled rocking cross-laminated timber walls without supplemental energy dissipation, including a method for estimating higher mode effects. Fragility analyses of three prototype walls demonstrate that the procedure can limit the probability of collapse to <10% during a maximum considered earthquake in a region of moderate seismicity.  相似文献   
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While the links between contaminated sites and adverse effects on human health and well‐being are being increasingly recognised, some argue that the magnitude of the health problem is inadequately addressed because it is largely invisible. Health geographies literature has sought to highlight this invisibility by focusing on the link between contaminated sites and health. This study adds to health geographies by presenting unique insights into the geography of residents' worry about the disruptive effect of environmental contamination on health and well‐being. It analyses a sample of residents (n = 485) living near 13 contaminated sites across Australia. Ordinal logistic regression analysis of closed‐format survey questions was combined with coding of open‐ended survey questions to reveal the geography of residents' worry about contamination from nearby sites. First, the study explores some of the main relationships between residents, their environs, and contaminants from nearby source sites, which determines their levels of worry: residents' demographics, residents' proximity to sites, contaminant boundaries and borders, and type of contaminant. Second, the study investigates how worry affects residents' health and well‐being, ranging from effects on their personal functioning through to their sense of ontological security, which depends in part upon their perceptions of contaminants' impacts. Despite having identified a range of diverse and negative effects of worry about contamination on residents, we found that worry for contamination can also prompt coping strategies and problem‐solving, reinforcing the need for more research on this subject.  相似文献   
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The article focuses on the redevelopment of previously developed land by public-private sector partnerships in three cities/towns in South-West England, two of which can be described as medium-sized places with little previous experience of such developments. In each case we situated the redevelopment process in its wider multi-level and horizontal relationships using Social Network Analysis to produce network and centrality maps to reveal the complex network of relationships the process was embedded within and shaped by. These developments took place in what is termed the ‘roll-out’ phase of neoliberalism and we illustrate how the overarching planning and regulatory regimes (including contracts), along with wider economic conditions, shaped the development process, with the proviso that in each case these factors were mediated and themselves shaped by the assortment and interaction of local organizational, political, economic and civic forces. These included local planning committees and their interpretation of planning regulations and the developers involved, but also opposition to the developments from local sources. Much, however, depended on the ‘capacity to act’ of the relevant partnerships, in the sense of mobilizing and deploying available resources to realize the proposed developments.  相似文献   
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Scholars considering the acoustics of exploration have focused on how explorers heard Australian space in terms of silence, to argue this silenced Indigenous presence, or that stillness, was incongruous with how a place to be colonised should sound. I focus on the acoustically attuned Ludwig Leichhardt, a science-poet indebted to the Enlightenment, but also engaged with the German Romantic legacy. The manifold acoustic dimensions of expeditioning – including music – were important to him in different ways. The acoustic world could be assayed and harnessed in ways that were often consistent with colonialism. But there was also something fugitive about acoustics. They could mark a site for emotional engagement with place, and sometimes embryonic cross-cultural dialogue. Yet the possibilities were not always heard and, in line with Romanticism, the acoustic could drag down expeditioners’ spirits just as it could buoy them up. It could baffle or be a site for Indigenous resistance.  相似文献   
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