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This paper discusses the general conditions which have given rise to megalithic construction techniques, and the specific circumstances under which megalithism became important in Neolithic Europe. It argues that the great elaboration of megalithic constructions in western and northern Europe must be related to the survival there of Mesolithic populations, and that monumentality was an essential element of the cultural rhetoric whereby these indigenous groups were converted to a Neolithic way of life.  相似文献   
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A growing number of respected commentators now argue that regulatory capture of public agencies and public policy by leading banks was one of the main causal factors behind the financial crisis of 2007–2009, resulting in a permissive regulatory environment. This regulatory environment placed a faith in banks own internal risk models, contributed to pro‐cyclical behaviour and turned a blind eye to excessive risk taking. The article argues that a form of ‘multi‐level regulatory capture’ characterized the global financial architecture prior to the crisis. Simultaneously, regulatory capture fed off, but also nourished the financial boom, in a fashion that mirrored the life cycle of the boom itself. Minimizing future financial booms and crises will require continuous, conscious and explicit efforts to restrain financial regulatory capture now and into the future. The article assesses the extent to which this has been achieved in current global financial governance reform efforts and highlights some of the persistent difficulties that will continue to hamper efforts to restrain regulatory capture. The evidence concerning the extent to which regulatory capture is being effectively restrained is somewhat mixed, and where it is happening it is largely unintentional and accidental. Recent reforms have overlooked the political causes of the crisis and have failed to focus explicitly or systematically on regulatory capture.  相似文献   
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This paper describes the design features and capabilities of a portable automated in‐situ closed chamber (ISCC) for the quantification of CO2 fluxes in dryland soils where both photosynthetic and respiratory components may be associated with a cyanobacterial crust. The processes of CO2 flux in dryland soils are briefly described in order to clarify the conditions that make quantification of these fluxes problematic. The instrumentation currently available for in‐situ soil CO2 flux measurements is then reviewed demonstrating their inadequacies for the dryland environment. The ISCC described here is a member of the closed or enrichment class of soil respiration chambers. The ISCC, however, features an optical window possessing high (>90%) transmission in the photosynthetic active region (PAR) of the solar irradiance spectrum, permitting observations of photosynthesis. The ISCC possesses automatic venting and purging so that gaseous concentrations inside the chamber do not change from ambient sufficiently to significantly affect diffusion. The ISCC features both active and passive cooling employing internal solid‐state Peltier coolers and external aluminised Mylar respectively. This avoids severe disturbance of the microclimate within the chamber due to admission of high fluxes of PAR and permits in‐situ operation under a wide range of ambient field temperatures (~ ?5 to 40°C). Sensors internal to the chamber monitor temperature, relative humidity, irradiance and pressure. In this implementation the ISCC is coupled to a portable gas chromatograph (Agilent GC‐3000) to sample the chamber atmosphere. Indicative data for Kalahari Sand soils of Botswana are presented as an illustration of the general performance characteristics.  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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In perhaps unexpected ways Britain has become quite closely linked to key aspects of EU migration and asylum policy. This could be a rather surprising outcome given that the UK is outside Schengen, opted out of the free movement, asylum and migration provisions of the Amsterdam Treaty and remains fixed on the maintenance of border controls at ports of entry to the UK. However, the differential and conditional engagement that has developed with EU migration and asylum policy has been described by Tony Blair as ‘getting the best of both worlds’. What could it mean to get the best of both worlds? Can the ‘two worlds’ of Britain and Europe be so neatly distinguished? To answer these questions the article surveys the extent of British engagement with EU migration and asylum policy and explains when, how and why the UK has opted into key aspects of it, particularly the more coercive components concerned with asylum and border controls.  相似文献   
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