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1.
The skeletal remains of 18 individuals interred at the ancient Maya site of Caledonia (100 to 1000 C.E.), located in the Cayo District of Belize, w ere sampled for stable carbon and nitrogen isotope analysis in order to reconstruct their diet. Stable carbon and nitrogen isotope ratios in 18 bone collagen samples and stable carbon isotope ratios in bioapatite from 15 bone and 6 tooth enamel samples were assessed. Small sample sizes precluded the assessment of dietary variation with respect to age, sex, social status or time period among the Caledonia Maya. However, the sampled individuals consumed a varied diet consisting of maize, supplemented with some C3 plants, terrestrial herbivores and/or lower order freshwater resources such as snails and molluscs and possibly maize‐fed animals. This dietary variability with an emphasis on maize is unsurprising given the biological diversity surrounding the site and the known importance of this crop to the ancient Maya. As expected, the isotopic values from Caledonia are similar to those from nearby sites from similar time periods. However, four individuals exhibit a marine dietary signature, possibly indicating inland trade of marine resources from coastal sites, or the migration of coastal people to Caledonia. This study demonstrates the validity of sampling small, fragmented collections from minor Maya centres in order to gain valuable insight into ancient Maya dietary practices. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
2.
This research aims at delineating the dietary practices in Central Italy during the Bronze Age. The study of food choices is a mean for investigating palaeoenvironmental agricultural and economic activities and social relationships, which have been little explored until now in Italy from this specific perspective. Recent researches have showed that the Middle Bronze Age is a crucial period of dietary changes in Italy. Following these first observations, we studied three Bronze Age sites in Tuscany and Latium: Grotta dello Scoglietto, Grotta Misa and Felcetone. Analyses of stable carbon, nitrogen and sulphur isotopes on 38 human and 22 animal collagen samples were performed. The results show three different dietary patterns. Data from Grotta dello Scoglietto (Early Bronze Age) indicate a high‐protein intake, with a probable consumption of fish. Additionally, sulphur results let us infer the presence of some non‐local people. Individuals from Felcetone (Initial phase of the Middle Bronze Age) show a terrestrial diet dominated by plant proteins, which suggests a low δ15N food intake, namely legumes, as well as C4 plant, such as millet. Finally, values from Grotta Misa (Middle Bronze Age) highlight a mixed terrestrial diet and the consumption of millet. Given the variety of the obtained results, we are able to conclude that the transition from the Early to the Middle Bronze Age represents a moment of change, which is reflected by the presence of different dietary patterns. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
3.
Excavations at the site of Bosutswe on the eastern edge of the Kalahari Desert in Botswana have uncovered over 4 m of deposit ranging in age from CE 700 to 1700. Our research has produced quantitative and qualitative measures of the material and ecological dimensions that structured the everyday actions and behaviors through which social identities were constituted, maintained, and transformed during the period when the polities of Toutswe, Mapungubwe, Great Zimbabwe and Khami rose to power. By examining the material dimensions that underlay shifting relations of production, exchange, and social stratification we are able to contextualize the social judgments that ascribed value to material goods and food ways, while specifying the ways these were used to create and naturalize social relationships and power differentials. Stable isotope analyses, combined with evidence of vitrified dung, further enable us to suggest changes in herd management strategies used by the inhabitants of the site to compensate for ecological changes brought about by long-term occupation, while at the same time enabling them to economically tie subordinates to them as social divisions became more rigidly defined after CE 1300. The cultural and economic changes that took place at Bosutswe thus directly impact our understanding of the social transformations that immediately preceded contemporary configurations of ethnicity in Botswana.  相似文献   
4.
The Mesolithic–Neolithic transition in north-west Europe has been described as rapid and uniform, entailing a swift shift from the use of marine and other wild resources to domesticated terrestrial resources. Here, we approach the when, what and how of this transition on a regional level, using empirical data from Öland, an island in the Baltic Sea off the Swedish east coast, and also monitor changes that occurred after the shift. Radiocarbon dating and stable carbon and nitrogen isotope analyses of bones and teeth from 123 human individuals, along with faunal isotope data from 27 species, applying to nine sites on Öland and covering a time span from the Mesolithic to the Roman Period, demonstrate a great diversity in food practices, mainly governed by culture and independent of climatic changes. There was a marked dietary shift during the second half of the third millennium from a mixed marine diet to the use of exclusively terrestrial resources, interpreted as marking the large-scale introduction of farming. Contrary to previous claims, this took place at the end of the Neolithic and not at the onset. Our data also show that culturally induced dietary transitions occurred continuously throughout prehistory. The availability of high-resolution data on various levels, from intra-individual to inter-population, makes stable isotope analysis a powerful tool for studying the evolution of food practices.  相似文献   
5.
中国特色社会主义文化纲领的历史发展   总被引:1,自引:0,他引:1  
从改革开放之初提出"两个文明"建设,到十五大正式提出"经济、政治、文化纲领",再到十六届四中全会发展为"物质文明、政治文明、精神文明、社会文明"四位一体,实质是中国特色社会主义事业总体布局的发展过程,是在这个总体布局中社会主义精神文明建设面临新任务、扮演新角色、承担新使命的过程,是中国特色社会主义文化纲领继往开来、不断丰富发展和完善的过程,反映了中国化马克思主义文化理论一脉相承、与时俱进的理论品质和实践品质。  相似文献   
6.
E. SHOCK  P. CANOVAS 《Geofluids》2010,10(1-2):161-192
Calculations are presented of the extent to which chemical disequilibria are generated when submarine hydrothermal fluids mix with sea water. These calculations involve quantifying the chemical affinity for individual reactions by comparing equilibrium compositions with the compositions of mixtures in which oxidation–reduction reactions are inhibited. The oxidation–reduction reactions that depart from equilibrium in these systems provide energy for chemotrophic microbial metabolism. Methanogenesis is an example of this phenomenon, in which the combination of carbon dioxide, hydrogen and methane induced by fluid mixing is far from equilibrium, which can be approached if more methane is generated. Similarly, the production of other organic compounds is also favorable under the same conditions that permit methanogenesis. Alkanes, alkenes, alcohols, aldehydes, carboxylic acids and amino acids are among the compounds that, if formed, would lower the energetic state of the chemical composition generated in mixed fluids. The resulting positive values of chemical affinity correspond to the thermodynamic drive required for abiotic organic synthesis. It is also possible that energy release accompanies biosynthesis by chemotrophic organisms. In this way, hydrothermal ecosystems differ radically from familiar ecosystems at Earth's surface. If captured, the energy released may be sufficient to drive biosynthesis of carbohydrates, purines, pyrimidines and other compounds which require energy inputs.  相似文献   
7.
The spatial and temporal variability of nitrogen dioxide (NO2) concentrations and their relationships with meteorology was evaluated in the Toronto–Hamilton urban airshed. NO2 concentrations were highest in the early morning and late evening. Mean concentrations were highest in winter, although individual one-hour NO2 concentrations were found to be highest in summer. Wind direction was the strongest control on hourly NO2 concentration, and temperature and wind speed also had an effect. Our analysis of NO2 concentration variation by wind direction showed that areas downwind of major highways, urban centres and industry were exposed to higher pollutant concentrations. Seasonal patterns of NO2 concentration displayed significant spatial heterogeneity, in particular, in Toronto. Onshore winds sheltered coastal inhabitants from the full extent of NO2 exposure they would otherwise experience. Seasonal variations in meteorology and emissions mean that the degree of spatial variability in NO2 concentrations changes from season to season. This study will help to improve existing land-use regression-based NO2 prediction models by incorporating meteorological controls on NO2 distributions for health effect studies.  相似文献   
8.
The incorporation of plant biomass into soil usually leads to long-chain n-alkanes with a relative predominance of odd carbon numbered homologues. Contrastingly, an increase in short-chain even carbon numbered n-alkanes was found in charred biomass with progressing temperatures. We applied lipid analysis to buried ancient topsoils that contained charred organic matter and to corresponding control soils, which were characterized by a lighter color and lower contents of charred materials. Commonly, the proportion of lipid extracts was found to be lower in the ancient soil than in the control samples, which indicated an enhanced degradation of organic matter, e.g., by thermal degradation. All samples displayed a particular pattern of short-chain and even carbon numbered n-alkanes (maximum at n-C16 or n-C18). The ratios CPI (carbon preference index) and ACL (average chain length) for the investigated soil samples matched the ratios found for maize and rye straw charred at 400 °C or 500 °C, respectively. These molecular ratios indicate the presence of charred biomass. The predominance of short-chain and even carbon numbered n-alkanes was a result of thermal degradation of biomass. The degradation products were preserved in ancient soils and could be applied as molecular markers in archaeological or palaeoenvironmental research.  相似文献   
9.
A large systematic dye investigation of prehistoric Danish and Norwegian bog textiles was carried out using high performance liquid chromatography with photo diode array detection. After the selection of the most suitable protocol for dye extraction and HPLC analysis for this specific group of archaeological samples, the second part included the characterisation of the dyes detected in the whole series of the Early Iron Age textiles and the interpretation of the dyeing technology. Natural organic dyes were found from the three main categories of natural dyes, hence throwing new light on the use of biological dye sources in Early Iron Age Scandinavia. The results clearly indicate that most Scandinavian peat bog textiles originally were dyed and that already during the 1st millennium BC, the populations in Scandinavia were familiar with the dyeing technology.  相似文献   
10.
Intra‐individual variations in carbon (δ13C) and nitrogen (δ15N) isotope measurements of dentine collagen in ungulate teeth can be related to diet and environmental changes at different periods during the life of the animal. A protocol of serial sampling of first, second and third molar roots was applied to modern caribou (17–27 months old) of the Qamanirjuaq herd (Rangifer tarandus groenlandicus), Canada. Based on a previous study, we predicted that M2 would reflect winter, M3 summer and M1 a complete year in terms of the isotopic record. Relatively high δ15N values (ca. 6 to 8‰), previously attributed to winter stress, were found in different molars of different specimens, reflecting a period of growth between April 1966 to April 1967. Previous results on other teeth from the same population confirmed that a high δ15Ncoll value signal corresponded to the winter of 1966/67. This temporary increase in δ15N value was probably linked to diet and/or environmental change. Collagen from M1 reflects the first winter whereas M2 and M3 reflect the second winter of life of young caribou. A longer time record including summer is represented by the bone collagen of the mandible. Results obtained on molar roots and mandible bone of the modern caribou of Banks Island herd (Rangifer tarandus pearyi) confirmed this seasonal record. Such collagen isotopic analysis on M1, M2 and M3 roots and jawbone can be applied to reindeer found in archaeological sites. Mandibles retaining deciduous premolars are preferable to avoid the possible loss of the winter tooth signal observed in animals older than 2 years. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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