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81.
Charles P. Loomis and J. Allan Beegle., A Strategy for Rural Change. New York: Halsted Press, 1975. xv + 525 pp. Tables, figures, references, author and subject indices. $19.50.  相似文献   
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Wood ash, composed mainly of the mineral calcite, is an important component in many archaeological sites. Identification of wood ash in the archaeological record is often difficult due to mixing of ash with other calcitic components of geogenic origin and/or due to diagenetic changes. A recent empirical study using the stable isotope compositions of carbon (δ13C) and oxygen (δ18O) in wood ash enabled the identification of mixtures of wood ash with geogenic calcite and to follow diagenetic changes due to partial dissolution and re-precipitation of ash in two prehistoric cave sites in Israel. Little however is known about the processes responsible for the isotopic compositions of wood ash in relation to formation at various temperatures and the influence on isotopic composition of ash from a variety of plant species. Here we present an experimental study of wood ash formed by burning three C3 tree species and one C4 desert bush at different temperatures. The results indicate that there are significant differences in the isotopic compositions of carbon and oxygen between wood ash that forms by combustion at a relatively low temperature (500 °C) and at a higher temperature (900 °C). In addition, we show that the isotopic composition of carbon and oxygen in high temperature wood ash approaches equilibrium over a period of several months and that the carbon isotopic composition of low temperature wood ash may reflect the photosynthetic pathway of the burnt woody species. Lastly, we show that the isotopic compositions obtained from wood ash prepared at different temperatures do not reflect a temperature dependent fractionation process, but a mixing line between calcite that formed by low temperature combustion and calcite formed by high temperature combustion which later underwent re-carbonation with atmospheric CO2. In addition, we suggest that exchange processes may possibly occur during combustion between decomposing calcium-oxalate and atmospheric O2, CO2 and CO. The archaeological implications of this study are discussed in relation to identification of wood ash in the archaeological record, identification of fuel sources and burning temperatures, and diagenetic changes expected in karstic cave environments. The method presented here can be applied at any archaeological site.  相似文献   
84.
Recent lidar and pedestrian surface surveys have remapped the well-known Mesoamerican site of Izapa and the surrounding Soconusco piedmont. These data document: 1) occupation from the surrounding piedmont environment, 2) significantly larger estimates of the site's size during both the Formative and Classic periods as well as 3) new architectural features from the monumental site core. Methodological issues are outlined for combining high precision lidar mapping with ground truthing and pedestrian survey that focuses on surface collection of temporally diagnostic artifacts. Results are presented for 670 mounds documented in an area of 43.1 sq km in and around the ancient capital of Izapa.  相似文献   
85.
This paper presents 19 AMS radiocarbon dates from nine pre-Hispanic Caribbean (Taíno/Lucayan) wooden sculptures in the British Museum collections, provenanced to Jamaica, Hispaniola and the Bahamas. Together with strontium isotope results and wood and resin identifications, these data build a material and chronological context for some of the most recognised examples of Taíno art – from duhos (ceremonial seats) and cemís (free standing depictions of deities, ancestors and spirits) to canopied stands used to hold hallucinogenic drugs during the cohoba ceremony. Each sculpture widens our understanding of Caribbean carving traditions, stylistic variation, chronologies and material resource utilisation. A group of three sculptures recovered from Carpenters Mountains, Jamaica, carved by AD 1300 and brought together as a ceremonial ‘set’, each appear to have had their inlays renewed over a century later, suggesting long-term use. Three key examples of the main Caribbean duho categories (high-back, low-back and extended), provide insights into the diversity of styles present in the region post-AD 1100. The British Museum's corpus enables an exploration of regional styles, and potentially the work of individual artists.  相似文献   
86.
During the ten years covered by this review, the foci of studies in palaeobotany of plant megafossils and certain non-palynological plant microfossils included Precambrian palaeobotany, early vascular plants, Palaeozoic pteridosperms, conifers, and angiosperms. Botanically orientated investigations displayed an increasing use of the electron microscope. Interpretations of palaeoecology and reproductive biology of fossil plants gained increasing momentum. Biostratigraphic studies underwent some new activation but generally took second place to the amount of morphological work. The number of palaeobotanists who completed or received their training during the decade augurs well for the future; there is still much to be done.  相似文献   
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From the eighteenth-century Macassan traders from the Indonesian Island of Sulawesi made regular visits to northern Australia, where with the help of Yol?u, Indigenous Australians living in north-east Arnhem Land, they collected trepang (sea cucumber) for trade. Along with sharing language, technology and culture, the Macassans and Yol?u involved built relationships that are celebrated today in Yol?u art, songs and stories. While the trepang trade had officially stopped by 1906, resonances of this complex relationship continued and still continue today. This paper shares a number of stories told by one particular Yol?u family about this heritage and reflects on the ways in which for Yol?u, the tangible heritage (artefacts), intangible heritage (stories) and the land itself are locked in a symbiotic relationship where each depends on the others to define their existence. Looking after, or protecting this heritage, is therefore about attending to place, and the nature, storytellers, objects and stories contained within it.  相似文献   
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In 1997, Italy's leading politicians began the overdue process of revising the existing constitution. The bicameral commission of parliament charged with this task has proposed significant alterations to the country's institutional structure. Innovations include a directly elected presidency, an end to bicameralism and a greater role for sub‐national tiers of administration. However, this article argues that the suggested changes are in fact less sweeping than they seem, and do not address the country's urgent need to move towards a more competitive form of democracy.  相似文献   
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