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Formation processes and chronology are central to many archaeological endeavours, and accuracy in the latter is dependent on control of the former. Here we consider how to integrate geoarchaeological and chronometric evidence to better understand the formational history, along with the timing and duration of cultural activities, at a regionally significant site in the southern Cook Islands (Polynesia) which dates from ∼12th century AD. Initially we model natural and cultural processes of deposition using geoarchaeological evidence. The results are integrated with 21 radiocarbon dates, including nine new AMS results on identified medium and short-lived materials. Sample outliers are identified manually and statistically and a Bayesian analysis helps to refine age estimates for the site's 12 stratigraphic zones. The timing and rate of sediment accumulation is further considered through an age–depth model. Finally, the chronology developed from these combined approaches is used to address three key processes: 1) initial site use, potentially relevant to human colonisation of this Polynesian island and archipelago; 2) on-site activities and patterns of resource use; and 3) major marine deposition events which disrupted cultural activities and may have palaeoclimatological significance. The approach developed here potentially has utility elsewhere, particularly where human activities are recurrent and of limited duration.  相似文献   
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Is it ever justifiable to target non‐combatants deliberately? This article assesses Michael Walzer's claim that the deliberate targeting of non‐combatants may be justifiable during ‘supreme emergencies’, a view that has received some support but that has elicited little debate. It argues that the supreme emergencies exception to the prohibition on targeting non‐combatants is problematic for at least four reasons. First, its utilitarianism contradicts Walzer's wider ethics of war based on a conception of human rights. Second, the exception may undermine the principle of non‐combatant immunity. Third, it is based on a historical fallacy. Finally, it is predicated on a strategic fallacy–the idea that killing noncombatants can win wars. The case for rejecting the exception, however, has been opposed by those who persuasively argue that it is wrong to tie leaders' hands when they confront supreme emergencies. The final part of the article addresses this question and suggests that the principle of proportionality may give political leaders room for manoeuvre in supreme emergencies without permitting them deliberately to target non‐combatants.  相似文献   
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The relationship between environmental variation and subsistence practices is a central point of discussion in much Oceanic archaeology. While human predation can significantly reduce prey populations, environmental variation also contributes to reductions in prey abundance, possibly leading to increased human competition and resource scarcity. At the Natia Beach site, Nacula Island, Fiji, geoarchaeological evidence suggests that coastal progradation began soon after initial occupation of the coastal plain. Additionally, at approximately 650 BP a marked increase in clay and silt deposition occurred. Changes in coastal geomorphology may be explained by landscape response to regional Mid-Holocene sea level fall combined with human induced soil erosion due to upland settlement. Smaller scale environmental changes associated with climate variability may have also played a role. Additionally, landscape change appears to have had a measurable impact on local nearshore mollusks that are sensitive to high levels of water turbidity. Minor evidence of human exploitation is observable in this shellfish assemblage, although changes in predation pressure may have allowed shellfish populations to recover. Increased ceramic diversity and fortified settlements also appear at approximately 650 BP on Nacula and other parts of Fiji. The suite of changes at Natia may be explained by processes of regional and local environmental changes, and human adaptation in terms of subsistence, spatial organization, and competition.  相似文献   
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王牧  Alex 《世界》2008,(2):153-157
不管我们到什么地方旅行,无论是面对金字塔,故宫,吴哥窟这些古迹,还是伦敦、巴黎或者纽约这些大城市里的博物馆,除了拍摄旅游纪念照以外,都希望拍出更好的图片来,至少能让我们在旅途结束之后面对相片能重拾起那些美好的记忆。  相似文献   
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There is a large body of literature devoted to how “policies create politics” and how feedback effects from existing policy legacies shape potential reforms in a particular area. Although much of this literature focuses on self‐reinforcing feedback effects that increase support for existing policies over time, Kent Weaver and his colleagues have recently drawn our attention to self‐undermining effects that can gradually weaken support for such policies. The following contribution explores both self‐reinforcing and self‐undermining policy feedback in relationship to the Affordable Care Act, the most important health‐care reform enacted in the United States since the mid‐1960s. More specifically, the paper draws on the concept of policy feedback to reflect on the political fate of the ACA since its adoption in 2010. We argue that, due in part to its sheer complexity and fragmentation, the ACA generates both self‐reinforcing and self‐undermining feedback effects that, depending of the aspect of the legislation at hand, can either facilitate or impede conservative retrenchment and restructuring. Simultaneously, through a discussion of partisan effects that shape Republican behavior in Congress, we acknowledge the limits of policy feedback in the explanation of policy stability and change.  相似文献   
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