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191.
The abundance, accessibility and value of limpets as a source of food and bait for coastal peoples have resulted in their high frequency in shell middens worldwide. The limpet Patella vulgata is found in middens from the Mediterranean to Norway, and morphometric and sclerochronological analyses of its shell can provide insight into harvesting patterns and paleoenvironmental variables valuable in reconstructing climate. Previous work with P. vulgata has relied on lines on the exterior of the shell, or on lines exiting on the shell surface in shell cross-section, as annual or sub-annual markers. Shell damage may compromise these lines and limit the use of some shells, but growth lines are also found in the better-preserved shell apex. We investigated whether the growth lines in the apex of P. vulgata from two locations in Northern Europe are annual using calcein-marking and recapture. Investigations were performed at one site in the Shetland Islands (UK) and at one site at the northern limit of P. vulgata's range in Northern Norway. We also used laser ablation to measure the concentration of minerals in the shells of two individuals from Shetland to determine if patterns of minerals suggested as bioproxies for temperature and productivity varied annually. All individuals deposited one growth line in the apex during their year in the field, and the lowest ratios of Sr/Ca and Ba/Ca and to a lesser extent Mg/Ca were coincident with annual lines on the shells from Shetland. Growth at both sites was modelled using the von Bertalanffy growth function, and apex growth was nearly five times faster in Shetland than in Norway, probably a result of differences in temperature between the two locations.  相似文献   
192.
The Full Hempel     
Book reviewed in this article:
The Logic of Historical Explanation by Clayton Roberts  相似文献   
193.
In this paper we extend the Harris-Todaro model of rural-to-urban migration to include urban agglomeration effects, some urban real wage flexibility, and a government budget constraint. Without employment subsidies laissez-faire migration is excessive unless real wage flexibility and agglomeration effects are high. Laissez-faire migration is too low compared with the first-best outcome supported by a subsidy, if its financing involves no costs. Simulations suggest that such a program would imply a substantial increase in taxation. If, as seems likely, an increase of this magnitude involves economic costs then the optimal outcome falls well short of first-best.  相似文献   
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The Italian Bell-Beaker (Final Copper Age) has been widely studied, yet little is known about its archaeofaunas. Reported are the results of the analysis of the archaeofauna from Semitella, which is one of the largest and most important Bell-Beaker sites in Italy. The site yielded an intentionally buried bovine skeleton and contained many pits, scattered throughout the excavated area. These pits may have originally contained the corpses of the animals whose bones are represented in the sample. The hypothesis is that Semitella was a sort of cemetery for animal carcasses, or a dumping ground where carcass discards and animal cadavers were thrown or buried. A careful taphonomic and zooarchaeological analyses were therefore mandatory. The study confirmed the hypothesis. It in fact revealed a poorly diversified, selected fauna, dominated by domestic taxa, matched to a strikingly low incidence of bone surface modifications, which is the expected state of bones that have been rapidly subtracted to biostratinomic agents. The accumulated evidence indicates that Semitella was a dumping and/or a burial ground for animal corpses in the surroundings of a nearby settlement. The assemblage's final arrangement is the result of floodings that removed the disarticulated skeletal parts scattering them downstream. What remains unresolved is whether, or not, the burials were connected with ritual practices.  相似文献   
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Abstract. This paper examines the initial location choice of legal employment‐based immigrants to the United States using Immigration and Naturalization Service data on individual immigrants, as well as economic, demographic, and social data to characterize the 298 metropolitan areas we define as the universal choice set. Focusing on interactions between place characteristics and immigrant characteristics, we provide multinomial logit model estimates for the location choices of about 38,000 employment‐based immigrants to the United States in 1995, focusing on the top 10 source countries. We find that, as groups, immigrants from nearly all countries are attracted to large cities with superior climates, and to cities with relatively well‐educated adults and high wages. We also find evidence that employment‐based immigrants tend to choose cities where there are relatively few immigrants of nationalities other than their own. However, when we introduce interaction terms to account for the sociodemographic characteristics of the individual immigrants, we find that the estimated effects of location destination factors can reverse as one takes account of the age, gender, marital status, and previous occupation of the immigrants.  相似文献   
200.
Geography's debates about how to maintain a sense of morally responsible action often emphasise the problematic nature of caring at a distance, and take for granted particular kinds of moral selfhood in which responsibility is bound into notions of human agency that emphasise knowledge and recognition. Taking commodity consumption as a field in which the ethics, morality, and politics of responsibility has been problematised, we argue that existing research on consumption fails to register the full complexity of the practices, motivations and mechanisms through which the working-up of moral selves is undertaken in relation to consumption practices. Rather than assuming that ethical decision‐making works through the rational calculation of obligations, we conceptualise the emergence of ethical consumption as ways in which everyday practical moral dispositions are re‐articulated by policies, campaigns and practices that enlist ordinary people into broader projects of social change. Ethical consumption, then, involves both a governing of consumption and a governing of the consuming self. Using the example of Traidcraft , we present a detailed examination of one particular context in which self‐consciously ethical consumption is mediated, suggesting that ethical consumption can be understood as opening up ethical and political considerations in new combinations. We therefore argue for the importance of the growth of ethical consumption as a new terrain of political action, while also emphasising the grounds upon which ethical consumption can be opened up to normative critique.  相似文献   
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