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Almost all archaeological ceramics undergo slow, progressive rehydroxylation by chemical combination with environmental water. The reaction is accompanied by an expansion, and also by the small but measurable mass gain that provides the basis of the RHX dating method. The rate of the RHX reaction increases with increasing temperature. Here we describe comprehensively the effects of temperature on the RHX process in relation to the dating methodology. We deal in turn with the kinetic model of the RHX reaction, the temperature dependence of the RHX rate, and the influence of varying environmental temperature on the RHX mass gain. We define an effective lifetime temperature and show how this is calculated from an estimated lifetime temperature history. Historical meteorological temperature data are used to estimate the lifetime temperature history, and this can be adjusted for long-term climate variation. We show also how to allow for the effects of burial in archaeological sites on the temperature history. Finally we describe how the uncertainties in estimates of RHX age depend on the estimates of temperature history and effective lifetime temperature.  相似文献   
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The Australian Labor Party, following its election to government in 2007, has implemented an ambitious social policy agenda with spending on hospitals, pensions and community workers, as well as programs for parental leave and disability. It has also reformed taxes, in part to finance these reforms, implementing the mining and carbon taxes in 2012. Labor, however, has difficulty avoiding deficits because tax revenues are too low to finance expanded welfare. This article explores the political constraints and opportunities involved in financing welfare by examining voter responses to the ANU Poll of September 2011. Spending on welfare is supported by low-income earners, while taxing big industries finds greater support among university-educated voters. The article advances an explanation for this mismatch and for why tax resistance has hindered Labor's efforts to finance welfare expansion.

澳大利亚工党在2007年选举上台后实施了雄心勃勃的社会政策计划,涉及医院、养老金、社区工作人员、带薪育婴假、残疾人等项开支。它还在2012年改革了税收,推行采矿及碳排放税为上述改革筹集资金。不过,工党苦于避免赤字,因为税收太少,资助不了扩大的福利。本文分析了选民对2011年9月ANU民调的回应,探讨了资助福利之举的限制与机遇。低收入者支持福利开支,受过高等教育者则多支持向大企业征税。本文解释了这种矛盾,以及为什反税收阻碍了工党资助福利扩张的努力。  相似文献   

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That the 1990s began and ended with wars in the Balkans, often evoking reference to ‘ancient hatreds’, might suggest little has been learned since the fall of the Wall on how to address the recrudescence of violent ethno‐nationalist conflict – and indeed some fatalism as to whether this can be done at all. Yet the rethinking of notions of national sovereignty, the increasing minority‐rights jurisprudence and the development of anti‐essentialist concepts of identity in recent times have begun to indicate new policy instruments which might better allow such conflicts to be managed in the twenty‐first century. As ever, however, policy lags behind intellectual innovations, and the predominant approach of the international community remains for the moment significantly more conservative in character.  相似文献   
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A copper‐alloy thimble was found in 2010 at Punta Secca, Sicily, in a sealed context datable by coins to the first quarter of the seventh century AD. It has generally been thought that thimbles did not reach the Mediterranean area until the ninth century AD, but at least nine metal examples are in fact attested at various places from contexts datable between the late sixth century and the early ninth. It is suggested that the increasing use of silk in clothing in the Byzantine Empire during the seventh century, probably accompanied by the use for the first time of steel needles which made the use of a finger protector imperative, explains the apparent introduction of thimbles at this time. No securely dated metal thimbles are known from sites of Roman date, except for one at Ephesus of c.AD 100. It is very tentatively suggested that this last example might represent an import from China, where thimbles (and steel needles) are attested from at least the third century BC onwards.  相似文献   
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