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31.
Summary.   Archaeologists have identified the adoption of new forms of cremation ritual during the early Roman period in south-east Britain. Cremation may have been widely used by communities in the Iron Age, but the distinctive nature of these new rites was their frequent placing of the dead within, and associated with, ceramic vessels. This paper suggests an interpretation for the social meaning of these cremation burial rites that involved the burial of ashes with and within pots as a means of commemoration. In this light, the link between cremation and pottery in early Roman Britain can be seen as a means of promoting the selective remembering and forgetting of the dead.  相似文献   
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Household CO2 emissions are a significant contributor to global greenhouse gas emissions and consequently climate warming. Despite this, there has been little consideration of how household CO2 emissions may be affected by changes in climate. The aim of the present study has been to investigate the way climate, as well as socio‐demographic characteristics, may affect household CO2 emissions produced from energy use. A national online survey was conducted to determine current household CO2 emissions in Australia as well as capture the ownership and use of household appliances and installations. Electricity and gas‐based emissions as well as the ownership of a variety of household appliances and installations were found to be strongly associated with temperature. Electricity and gas emissions were found to decrease as annual average temperatures increase. However, as temperatures continue to rise under climate change this pattern may be reversed owing to increased reliance on air conditioners. One option for preventing this from occurring is to encourage houses to adopt more solar‐passive installations. Although this may be expensive, households with higher emissions tend to have higher incomes, indicating that they may have the capacity to pay for such installations.  相似文献   
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The formation and subsequent healing of cracks and crack networks may control such diverse phenomena as the strengthening of fault zones between earthquakes, fluid migrations in the Earth's crust, or the transport of radioactive materials in nuclear waste disposal. An intriguing pattern-forming process can develop during healing of fluid-filled cracks, where pockets of fluid remain permanently trapped in the solid as the crack tip is displaced driven by surface energy. Here, we present the results of analog experiments in which a liquid was injected into a colloidal inorganic gel to obtain penny-shaped cracks that were subsequently allowed to close and heal under the driving effect of interfacial tension. Depending on the properties of the gel and the injected liquid, two modes of healing were obtained. In the first mode, the crack healed completely through a continuous process. The second mode of healing was discontinuous and was characterized by a 'zipper - like' closure of a front that moved along the crack perimeter, trapping fluid that may eventually form inclusions trapped in the solid. This instability occurred only when the velocity of the crack tip decreased to zero. Our experiments provide a cheap and simple analog to reveal how aligned arrays of fluid inclusions may be captured along preexisting fracture planes and how small amounts of fluids can be permanently trapped in solids, modifying irreversibly their material properties.  相似文献   
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An understanding of the nature and magnitude of hydrological, physical habitat and physico‐chemical effects resulting from surface‐water diversions in river systems is essential for effective management of water resources. For most coastal‐draining rivers in New South Wales, however, there are few data available on irrigation diversions, their hydrological impacts and environmental effects. This paper therefore presents an analysis of mean daily surface‐water diversions for pasture irrigation from approximately three years of metered data and the resultant effects on daily flows and aquatic habitats in the Bega‐Bemboka River. The period of analysis of the hydrological effects of irrigation diversions is extended to the full length of record (approximately five years) for gauging stations most affected by irrigation diversions, using Maintenance of Variance Extension Type 1 (MOVE.1) modelling techniques. The annual mean, median and peak daily rates of water diversion by metered surface‐water licences used to irrigate 925 ha of dairy pasture are 10.5 Ml d?1, 7.3 Ml d?1 and 41.5 Ml d?1, respectively. Diversion effects on flow duration statistics are such that the measured 90th and 95th daily flow duration percentiles at the gauging station most affected by upstream irrigation diversions are equivalent to the 97th and 99th flow duration percentiles, respectively, under MOVE.1 modelled natural flow conditions. While diversions for irrigation over the three‐year data period account for only 6.6% of total flow volumes, diversions as a proportion of daily surface‐water inflows increase exponentially under decreasing flow rates. Median and maximum daily diversion rates attain 91% and 118%, respectively, of total surface‐water inflows to the diversion‐affected reach when upstream inflows range from 15 to 20 Ml d?1. This exponentially‐increasing relationship between daily diversion rates and declining surface‐water inflows suggests that ‘rule of thumb’ guidelines on sustainable diversion limits based on mean or median annual percentage diversion volumes need to be applied cautiously to river systems with no or limited capacity to manipulate flows to meet downstream consumptive demands.  相似文献   
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Before the 1978 excavation of the chapter-house site directed by Martin Biddle and the late Birthe Kjølbye-Biddle, nothing was known about the 15th-century building, beyond the brief documentary references in the Register to its remodelling during the second half of the century in the time of abbots John of Wheathamstead and William Wallingford. However, the exceptional quantity of late Gothic masonry fragments uncovered during the excavation has made it possible to attempt to reconstruct features of its design, particularly the vaulting, and has transformed our knowledge of this important building. This article reviews the information derived from the study of the fragments of the vault, assesses its significance in the development of late Gothic vaulting, and speculates on the identity of its designer.  相似文献   
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International development is in a period of transition. While the outcome of this is still unclear, this article argues that there are at least four areas in which the project of international development is changing. First, there is a debate, especially within the World Bank, about development strategy and how we think about development, particularly in terms of the balance between states and markets. This is evident in the debate over state failure and the new structural economics. Second, there is increasing evidence of a shift in lending, away from projects of ‘small’ human development, perhaps best encapsulated by the United Nations Millennium Development Goals, towards more transformative ‘big’ development projects such as infrastructure. Third, ‘non‐traditional’ aid donors and new forms of private philanthropy are playing a more significant role in development financing and this, in turn, offers developing countries a new range of choices about what kinds of development assistance they receive. Fourth, aid relations are changing as a result of the renewed agency of developing states, particularly in sub‐Saharan Africa, and shifts towards increased South–South cooperation are growing as evidenced by increased funding from regional development banks and increased trade flows. The article reviews these changes and suggests a series of questions and challenges that arise from them for analysts of international development, developing countries and traditional aid donors.  相似文献   
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