The ‘Sand-Bath’ and Lithic Heat Treatment in the South African Middle Stone Age: Myth or Reality?

When heat treatment of silcrete for stone knapping was first discovered in the South African Middle Stone Age (MSA), the procedure used for it was suggested to be similar to the one used for heat treatment of finer rocks in other parts of the world: slow sand-bath heating. This comparison may have been based on published data from the fields of ethnography, experimentation and archaeology, describing sand-bath like structures and processes. In this review, I discuss whether the available data from these three fields indeed justify the suggestions that sand-bath heating was used in the context of MSA silcrete heat treatment. A careful revaluation of the available data shows that, although sand-bath heating is a widely accepted procedure that is documented in other parts of the world, understanding the earliest known cases of heat treatment in the MSA calls for another technical procedure.     

古村落景区游客拥挤感知维度与游憩情绪影响机制研究——以西递、宏村为例

拥挤感知被认为是影响游客的游憩体验和满意度的重要指标,通过构建拥挤感知的多维度变化来探讨游客情绪的变化对满意度的影响研究仍不成熟。本文以西递、宏村为研究案例地,运用结构方程模型分析方法,构建空间拥挤、人潮拥挤和体验拥挤维度对游客游憩过程的影响模型,探讨了游客拥挤三个维度的影响因素。研究表明：①人潮拥挤对情感依附型游客积极情绪呈正向影响;②空间拥挤增加消极情绪,与游客满意度呈负相关关系;③体验拥挤对游客积极情绪呈显著负向影响;④人潮拥挤-积极情绪-满意度（0.359）之间的相互关系强于人潮拥挤-消极情绪-满意度（0.128）;空间拥挤-积极情绪-游客满意度（-0.241）的关联度强于空间拥挤-消极情绪-游客满意度（-0.142）;体验拥挤-积极情绪-游客满意度（-0.167）之间的影响关系弱于体验拥挤-消极情绪-游客满意度（-0.213）;⑤人口特征对拥挤感知的影响差异显著。     

Systems and Boundaries in International History

The recent transnational, global, and cultural turns have challenged international historians to reconsider the approach, purpose, and value of their field. Although the new trends are beneficial to the extent that they challenge the premise that the nation-state should be the primary framework of historical inquiry, the boundaries of international history have expanded too far, and the cultural turn's preoccupation with national discourses at the expense of international structures and processes is diverting the field away from the analysis of the causes of war and the conditions of peace. The author argues that international history should distinguish itself from global and transnational history by drawing clear yet open disciplinary boundaries. Every field of inquiry needs some consensus about what it is, where it is going and why: in other words, an identity, purpose, and values. The author argues that what defines international history is its focus on the origins, structures, processes, and outcomes of international politics, above all the causes of war and the conditions of peace.