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991.
G. Giachi M. Mori Secci O. Pignatelli P. Gambogi M. Mariotti Lippi 《Journal of archaeological science》2010
A pile-dwelling settlement, dated to the final Bronze–early Iron Age (XII–XI century BC), was excavated at Stagno, near Leghorn (Tuscany, Italy). The site presented a well-preserved portion of the wooden foundation structure buried by sediments rich in plant remains: both wood and plant remains were subjected to archaeobotanical investigation. The ultimate goal was to improve our knowledge on agricultural economy and wood usage in Tuscany during the prehistoric ages. The results pointed to a farming system based on Triticum spp. (wheat), Hordeum spp. (barley) and Leguminosae cultivation in addition to the gathering of wild fruits, such as Corylus avellana, Cornus mas, Prunus spp., Vitis spp. Many of these plant remains are associated to a wetland context. Mesohygrophilous trees, such as deciduous Quercus, Ulmus minor, Fraxinus cf. excelsior, and Sorbus were used for the construction of the pile-dwelling structures; the choice of these plants indicates a good knowledge of the technological characteristics of timber. 相似文献
992.
Italian district small and medium enterprises (SMEs) developed aggressive strategies to extend their sales networks and supply chains abroad. Literature on districts offered alternative explanations about the impacts of internationalization on local manufacturing systems. The authors consider the evolution of Italian districts in the framework of global value chain approach, focusing on the role of leading firms. Based on a survey of 650 Italian SMEs and financial indicators, the paper describes the rise of a new district firm model, the open network, which becomes a key node of global value chains. The paper also analyses the relationships among internationalization, innovation strategies and performance of SMEs. 相似文献
993.
Verônica Wesolowski Sheila Maria Ferraz Mendonça de Souza Karl J. Reinhard Gregório Ceccantini 《Journal of archaeological science》2010
To date, limited numbers of dental calculus samples have been analyzed by researchers in diverse parts of the world. The combined analyses of these have provided some general guidelines for the analysis of calculus that is non-destructive to archaeological teeth. There is still a need for a quantitative study of large numbers of calculus samples to establish protocols, assess the level of contamination, evaluate the quantity of microfossils in dental calculus, and to compare analysis results with the literature concerning the biology of calculus formation. We analyzed dental calculus from 53 teeth from four Brazilian sambaquis. Sambaquis are the shell-mounds that were established prehistorically along the Brazilian coast. The analysis of sambaqui dental calculi shows that there are relatively high concentrations of microfossils (phytoliths and starch), mineral fragments, and charcoal in dental calculus. Mineral fragments and charcoal are possibly contaminants. The largest dental calculi have the lowest concentrations of microfossils. Biologically, this is explained by individual variation in calculus formation between people. Importantly, starch is ubiquitous in dental calculus. The starch and phytoliths show that certainly Dioscorea (yam) and Araucaria angustifolia (Paraná pine) were eaten by sambaqui people. Araceae (arum family), Ipomoea batatas (sweet potato) and Zea mays (maize) were probably in their diet. 相似文献
994.
Geographical development economics as reflected in the recent report by World Bank (2009) Reshaping Economic Geography (henceforth WDR-2009) and Sachs' (2005) End of Poverty has placed geographical factors of distance and density at the core of economic development. However, development geography has largely moved beyond a paradigm of modernity. This article seeks to narrow the above disciplinary divide and suggests that explanations of distance and density are not irrelevant but will need to be better integrated to local knowledge, practices and power relations in development schemes which are valued by development geographers. The latter is examined in the context of micro-credit programmes in two lagging areas, Soc Son and Vinh Loc, in northern Vietnam. Drawing from interviews and surveys of 160 female participants, we show that micro-credit, WDR-2009 and Sachs' geographical variables significantly affect poverty levels. However, qualitative interviews also reveal that the effects of distance, density and micro-credit schemes are constituted differently in the two areas. Relative to their Vinh Loc counterparts, Soc Son's participants experience less distance and density problems but are confronted with greater vulnerability to coercive relations of rule. In contrast, the approach to rule in the more geographically distressed area of Vinh Loc is underscored by flexibility and compromise which seek to cultivate conditions that sustain local livelihoods. 相似文献
995.
Maria Anna Pabst Ilse Letofsky-Papst Maximilian Moser Konrad Spindler Elisabeth Bock Peter Wilhelm M.D. Leopold Dorfer Jochen B. Geigl Martina Auer Michael R. Speicher Ferdinand Hofer 《Journal of archaeological science》2010
From a 1000-year-old mummy, found unwrapped in the sand of the desert at Chiribaya Alta in Southern Peru, two different kinds of tattoos were investigated: decorative tattoos displaying different animals and symbolic ciphers were present on the extremities and tattooed circles on the neck region. 相似文献
996.
997.
998.
The oceanic upper crustal reservoir is a 600‐m thick layer of porous and permeable basaltic rock that forms the uppermost igneous basement underlying the global ocean. Pore spaces within this fluid aquifer contain a significant fraction of the global seawater, and active circulation through this reservoir has profound influence on the chemical composition of the ocean, strongly impacting the biological environment near the sea surface. Because of the relative inaccessibility of the deep seafloor, where hydrothermal fluid discharges and seawater re‐charges the oceanic crustal aquifer, our understanding of the dynamic physical, chemical and biological processes is strongly dependent on our ability to obtain uncontaminated samples from this challenging environment. Recent technological advances have addressed some, but certainly not all of these sampling problems, providing new data and samples that test our current hypotheses about the crustal fluid reservoir. Current scientific interest in the sub‐seafloor biosphere has focused on the uppermost igneous oceanic crust as likely to be one of the most habitable environments, because of its porosity and locus of hydrothermal circulation of chemical nutrients. Recent observations indicate that sub‐seafloor crustal environments harbor novel CO2‐utilizing bacteria (primary producers) that could be a significant source of carbon‐fixation in the ocean, thus broadening possible habitable zones both on Earth and elsewhere where microbial life could exist independent of nutrient input from photosynthesis. 相似文献
999.
N. H. S. OLIVER M. J. RUBENACH B. FU T. BAKER T. G. BLENKINSOP J. S. CLEVERLEY L. J. MARSHALL P. J. RIDD 《Geofluids》2006,6(4):346-358
The source and transport regions of fluidized (transported) breccias outcrop in the Cloncurry Fe‐oxide–Cu–Au district. Discordant dykes and pipes with rounded clasts of metasedimentary calc–silicate rocks and minor felsic and mafic intrusions extend several kilometres upwards and outwards from the contact aureole of the 1530 Ma Williams Batholith into overlying schists and amphibolites. We used analytical equations for particle transport to estimate clast velocities (≥20 m sec?1), approaching volcanic ejecta rates. An abrupt release of overpressured magmatic‐hydrothermal fluid is suggested by the localization of the base of the breccias in intensely veined contact aureoles (at around 10 km, constrained by mineral equilibria), incorporation of juvenile magmatic clasts, the scale and discordancy of the bodies, and the wide range of pressure variation (up to 150 MPa) inferred from CO2 fluid inclusion densities and related decrepitation textures. The abundance of clasts derived from depth, rather than from the adjacent wallrocks, suggests that the pressure in the pipes was sufficient to restrict the inwards spalling of fragments from breccia walls; that is, the breccias were explosive rather than implosive, and some may have vented to the surface. At these depths, such extreme behaviour may have been achieved by release of dissolved fluids from crystallizing magma, in combination with a strongly fractured and fluid‐laden carapace, sitting under a strong, low permeability barrier. The relationship of these breccias to the Ernest Henry iron‐oxide–Cu–Au deposit suggests they may have been sources of fluids or mechanical energy for ore genesis, or alternately provided permeable pathways for later ore fluids. 相似文献
1000.
Mireia Baylina Ferré Anna Ortiz Guitart Maria Prats Ferret 《Children's Geographies》2006,4(2):173-183
This paper presents the first results of a case study on the ways in which playgrounds are constructed and experienced in children's daily lives in two medium sized Mediterranean Catalan cities. The research is based on qualitative methodology through participant observation and interviews with institutional actors. Our research suggests that playgrounds are organised around age as the central category; nevertheless, gender is important in the use and activities developed as children get older. Specific aspects from Mediterranean and medium-sized cities are raised such as a positive perception and an intense use of public space by both adults and children. Specific childhood policies in city planning and a stronger gender awareness among institutional actors would improve the social role of playgrounds as participatory, socialising and inclusive spaces. 相似文献