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Dental caries is an important condition to record in archaeological collections, but the way in which recording is carried out has a large effect on the way in which the results can be interpreted. In living populations, dental caries is a disease that shows a strong relationship with age. Both the nature of carious lesions and their frequency change with successive age groups from childhood to elderly adulthood. There is also a progression in the particular teeth in the dentition which are most commonly affected and, in general, the molars and premolars are involved much more frequently than the canines and incisors. Lower teeth are usually affected more than upper, although the condition usually involves the right and left sides fairly equally. In the high tooth wear rate populations represented by many archaeological and museum collections, there is a complex relationship between the form of lesions and the state of wear, which adds yet another range of factors to the changing pattern of caries with increasing age. In the same populations, chipping, fracture and anomalous abrasion of teeth are also common, and these contribute similarly to the distribution and forms of carious lesion observed. Amongst the living, the pattern of ante‐mortem tooth loss is important in understanding caries and, in archaeological material, there is also the complicating factor of post‐mortem tooth loss. Finally, there is the question of diagnosis. There are diagnostic problems even in epidemiological studies of living patients and, for archaeological specimens, diagenetic change and the variable preservation of different parts of the dentition add further complications. For all these reasons, it is difficult to define any one general index of dental caries to represent the complete dentition of each individual, which would be universally suitable for studying a full range of collections from archaeological sites or museums. Variation in the nature of collections, their preservation, tooth wear, and ante‐mortem and post‐mortem tooth loss mean that when such a general index appears to differ between sites, there could be many other reasons for this, in addition to any genuine differences in caries incidence and pattern that might have been present. It is suggested here that the best approach is instead to make comparisons separately for each tooth type, age group, sex, lesion type and potential lesion site on the tooth. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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Poll results vary over the course of a campaign election and across polling organisations, making it difficult to track genuine changes in voter support. I present a statistical model that tracks changes in voter support over time by pooling the polls, and corrects for variation across polling organisations due to biases known as ‘house effects’. The result is a less biased and more precise estimate of vote intentions than is possible from any one poll alone. I use five series of polls fielded over the 2004 Australian federal election campaign (ACNielsen, the ANU/ninemsn online poll, Galaxy, Newspoll, and Roy Morgan) to generate daily estimates of the Coalition's share of two-party preferred (2PP) and first preference vote intentions. Over the course of the campaign there is about a 4 percentage point swing to the Coalition in first preference vote share (and a smaller swing in 2PP terms), that begins prior to the formal announcement of the election, but is complete shortly after the leader debates. The ANU/ninemsn online poll and Morgan are found to have large and statistically significant biases, while, generally, the three phone polls have small and/or statistically insignificant biases, with ACNielsen and (in particular) Galaxy performing quite well in 2004.  相似文献   
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Abstract. The paper proposes a human capital‐based model of choice between paid employment and entrepreneurship that can give rise to multiple equilibria in occupational structure. The model is consistent with evidence of pronounced, persistent, and hitherto unexplained regional variations in entrepreneurship. Whether multiple equilibria emerge is shown to depend on the occupation‐specific productivity of human capital and the costs of human and financial capital. The paper goes on to discuss the implications for governments seeking to promote entrepreneurship as a tool of regional development policy.  相似文献   
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Drawing on poststructuralist political ecology, the narratives of two struggles about siting a superquarry are examined to elucidate the complex articulations of community, nature, resistance and identity in play in public debates. Focusing on the discursive formulations of the quarry in the expert language, as well as in the arguments of both local proponents and opponents of the quarries, shows the importance of ontological categories in "environmental" siting disputes. In Harris, these themes rearticulate the histories of dispossession, crofting and religion, as well as complex layers of geographical identity in the various claims to community. In Cape Breton, the rethinking of aboriginal Mi'kmaq identity was stimulated by revived interest in the religious traditions linked to the sacred site near the proposed quarry. In light of these findings, the complexity and active rearticulation of local "community" as political resistance are emphasised and the difficulties of thinking about sustainability highlighted.  相似文献   
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Memories of headhunting, and ritual re‐enactments of those former violent practices, are still politically meaningful in contemporary Oceania and Southeast Asia. The case of the Sejiq of Taiwan illustrates how such practices were transformed and eventually terminated as a result of colonialism and the incorporation of formerly stateless peoples into new political institutions. Headhunting was once an expression of the sacred law of Gaya, as both a reinforcement of territorial boundaries and a way of settling legal disputes within communities. It expressed tensions in a ‘reverse dominance hierarchy’ by which some men tried to consolidate political power, but were usually deterred by a strong egalitarian ethos. During the period of Japanese administration (1895–1945), new technologies made headhunting more efficient, but it became more difficult for this formerly egalitarian people to avoid the political coercion of would‐be leaders. Contradictions between headhunting as the implementation of Gaya and headhunting as a consolidation of political power — itself viewed as a violation of that Law — eventually led to the abandonment of headhunting. Local leaders found new ways to seek political power, including in the ritual re‐enactment of the very same practices used by their ancestors, but continue to be resisted by ordinary people with an egalitarian ethos.  相似文献   
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Through use of methodology common in sedimentary geology, we apply U–Pb ages of detrital zircons to source nonlocal temper sand in an ancient ceramic assemblage recovered from Roviana Lagoon of the New Georgia Group in the Solomon Islands. Most potsherds from the Roviana Lagoon contain local volcanic sand as temper, but a small number of sherds contain anomalous granitic temper sand that does not appear to be local. To determine the origin of the anomalous temper, ages of zircons from the anomalous Roviana sherds are compared with ages of zircons in materials from Lizard Island off the Queensland coast and in sand from Muyuw Island in the Solomon Sea where generically similar granitic sands occur. U–Pb analyses of grains from the Roviana sherds yield Middle Miocene ages, while analyses of grains from Lizard Island granitic bedrock, sand, and local potsherds yield much older Permian-Triassic ages, disproving any possibility that the Roviana sherds were derived from Lizard Island, but suggesting local production of the Lizard Island sherds. Ages of grains in a sand sample from Muyuw Island are nearly identical to the ages of grains in the Roviana sherds. All grains in the Muyuw sand are Middle Miocene in age, overlapping closely with the Roviana age population. This strong similarity in detrital zircon signals indicates that the Roviana temper was likely derived from Muyuw Island sands. Our test case for the use of U–Pb ages of detrital zircons in sourcing temper sands is of only regional significance, and not of intrinsic global interest. The methodology, however, should find wide applicability for sourcing temper sands in many parts of the world, for it provides more specific data for the origins of tempers than either petrographic or chemical analysis.  相似文献   
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