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951.
952.
The essay shows that the axiomatics of the systemic‐cybernetic‐biological theory of self‐organization by Humberto Maturana and Francisco Varela have their roots in the philosophy of German Idealism. Especially the completely subject‐centered philosophy of Johann Gottlieb Fichte already contains the central axiomatics of Maturana and Varela. 相似文献
953.
Abstract: This article, based upon in-depth interviews with anti-governmentleaders and activists, first explains the significance of theupheaval in Communist Poland in 1980–1981 and articulateshow the author became involved in this research and explainshis methodology. It then concentrates on the impact on the personallives of the participants and on social relations in Polandof the upheaval that produced an unprecedented-in-the-Soviet-blocindependent union with the right to strike. It shows how activistsdeveloped talents and cultivated abilities as they assumed responsibilitiesthat had previously been unavailable to them. It examines howworkers' lives changed as they grasped control of power: theirworking conditions improved; their status rose; they treatedone another better; they educated themselves. These changes,which contributed to the context in which the political struggleof that period took place, survived the suppression of the unionand ultimately contributed to bringing about the end of Communismin Poland. 相似文献
954.
Archaeological bone can show marked and complex alterations depending on the environment in which it was buried. In this study, the state of preservation of 27 femurs recovered from the archaeological site of Pompeii was evaluated by light microscopy and scanning electron microscopy. Most of the bone samples, prepared by the grinding method, showed good histological preservation, although they were characterized by microfissures (microcracking). Nine bone samples showed different states of histological preservation, including worst preservation (two femurs), due to diagenetic processes. Cryostat bone sections stained with thionin or 4′,6′-diamidino-phenylindole (DAPI) revealed the persistence of DNA within some osteocyte lacunae. Scanning electron microscopy analysis showed that ultrastructural characters, such as lamellae and collagen fibres, are recognizable only in unaltered bone. Our results reveal that most Pompeian samples are well preserved since they have a bone microstructure virtually indistinguishable from that of fresh bone. In methodological terms, although each of the various morphological methods used contributes information, histological and histochemical analyses are the most informative for studying the preservation state of bone and allow for rapid essential screening of archaeological bone. 相似文献
955.
The extent to which North Atlantic Holocene climatic perturbations influenced past human societies is an area of considerable uncertainty and fierce debate. Ireland is ideally placed to help resolve this issue, being occupied for over 9000 yr and located on the eastern Atlantic seaboard, a region dominated by westerly airflow. Irish bog and lake tree populations provide unambiguous evidence of major shifts in surface moisture through the Holocene similar to cycles recorded in the marine realm of the North Atlantic, indicating significant changes in the latitude and intensity of zonal atmospheric circulation across the region. To test for human response to these cycles we summed the probabilities of 465 radiocarbon ages obtained from Irish archaeological contexts and observe enhanced archaeological visibility during periods of sustained wet conditions. These results suggest either increasing density of human populations in key, often defensive locations, and/or the development of subsistence strategies to overcome changing conditions, the latter recently proposed as a significant factor in avoiding societal collapse. Regardless, we demonstrate environmental change is a significantly more important factor in influencing human activity in the landscape than has hitherto been acknowledged. 相似文献
956.
Previous studies of patterns of osteoarthritis involvement in prehistoric skeletal populations have been used to suggest differences in lifestyle or subsistence patterns. In spite of the intriguing nature of such studies, inadequate controls for the potential confounding effects of age have made results less secure than they appear. While researchers remain unable to control for the inherent limitations imposed by preservation bias, meaningful advancement could be made in the analysis of these data. Here we propose two methods from epidemiology that would allow more robust comparisons between populations with differing age-structures: age-adjustment and logistic regression. We apply these two methods to previously published data from prehistoric populations of the American Great Basin. In doing so, we are able to discern sex differences in risk for osteoarthritis at the shoulder (beta = −1.82, SE = 0.74, OR = 0.16, 95% CI = 0.04–0.69, p = 0.013), elbow (beta = −2.07, SE = 0.82, OR = 0.13, 95% CI = 0.03–0.63, p = 0.011), and in the foot (beta = −3.11, SE = 1.57, OR = 0.04, 95% CI = 0.00–0.97, p = 0.048), that were not noted in previous analyses of these data. These findings suggest that greater clarity of results and more precise comparisons of risk may be achieved by using these methods. We conclude that further application of these methods to bioarchaeological studies would potentially improve what can be said about prehistoric health patterns and lifeways. 相似文献
957.
Small angle neutron scattering and neutron phase analysis techniques have been for the first time jointly employed to extract microscopic parameters of ceramic samples prepared under controlled conditions, in an attempt to establish a protocol for deriving information on the firing process. Data have also been collected on two series of early medieval samples from the Italian regions of Cuma and Miseno. The variation of the microscopic features observed on these samples could mirror some technological evolution in the period spanning from the 6th to the 12th century AD. 相似文献
958.
T. Delgado-Darias J. Velasco-Vázquez M. Arnay-de-la-Rosa E. Martín-Rodríguez E. González-Reimers 《Journal of archaeological science》2006
In the prehispanic Gran Canaria there are some anthropological differences between the coastal inhabitants who buried their dead mainly in tumuli, and those from the central mountains, mainly buried in caves. Some data, as the prevalence of auricular exostoses, and a different bone Ba/Sr ratio support the view that there were differences in economy and diet between both groups of islanders. Moreover, the proportion of carious teeth was significantly higher among the population buried in caves. In the present study we analysed the prevalence of dental calculus, periodontal disease and antemortem tooth loss in remains of 791 individuals belonging to the anthropological collection of the Museo Canario (Las Palmas). Calculus deposition was very frequent (88.51%), no differences existing between men and women or between those interred in tumuli or in caves. Age at death was the only parameter independently related to calculus deposition by stepwise multivariate analysis. Periodontal disease was observed in 66.78% of the population, significantly more in men (χ2 = 4.88, P = 0.027). No differences existed between individuals buried in tumuli and in caves. Antemortem teeth loss was observed in 64.73% of individuals, no differences existing between men and women or between those interred in tumuli or in caves. There was a significant association between calculus and periodontal disease (χ2 = 18.07, P < 0.0001). Both caries (χ2 = 8.40, P = 0.004) and periodontal disease (χ2 = 44.96, P < 0.0001) were associated with tooth decay. However, the proportion of teeth with calculus deposition (in relation to observed teeth) was significantly higher among the population buried in tumuli (Z = 3.18, P = 0.001), although no differences were observed when the proportion of antemortem lost teeth and alveoli with periodontal disease were compared among people buried in tumuli and in caves, but women showed significantly lower proportions of alveoli with periodontal disease and antemortem tooth decay. These data suggest that the population buried in caves had a different dietary pattern to that of those buried in tumuli, since calculus deposition -more frequent in the latter-may be related to the consumption of proteins. The results also point to the existence of differences in diet between men and women. 相似文献
959.
Jute cultivation in the Lower Amazon, 1940–1990: an ethnographic account from Santarém, Pará, Brazil
The Amazon region has long been a place of economic booms and busts. Much attention in the historical literature on Amazonia has focused on the largest and most famous regional economic boom, the Rubber Boom, a period of sustained economic prosperity for some from 1860 to 1920. Other ‘booms’ have occurred in the region as well and this paper describes and discusses one of those others. The paper demonstrates how an export economy in a global periphery (coffee in Brazil) affected economic development in a periphery of that same country and makes a methodological contribution by demonstrating how ethnographic research can contribute to an understanding of a historical period when the paper trail is weak.Jute, a fiber crop, dominated agricultural production along the Amazon River floodplain in the reach between Manaus and Santarém, Brazil, from the late 1930s until the early 1990s. The crop was introduced to the region by Japanese immigrants in order to supply the demand for jute sacking in the south of Brazil where such sacks were used to package commodities, especially coffee. Local smallholder cultivators grew and processed jute, production being mediated initially through Japanese middlemen, later by Brazilians. Poor fiber quality, several external shocks, including the removal of tariffs on imported jute, and especially changes in commodity packaging such as bulk handling and the use of synthetic sacks instead of jute sacks for the transport of coffee beans, the Amazonian jute market collapsed in the early 1990s. Despite its collapse, the legacy of the boom is still evident in the physical and social landscapes in the region. 相似文献
960.
Discovery of the zahrah carving tool on a trip to the Ru'us al-Jibal/Musandam Peninsula provided the impetus for the following ethnoarchaeological examination. Ethnographic information recovered from numerous interviews is outlined in detail. The connection between the various carving tools used by the Shihuh tribes in this region and the dot-in-circle motif is investigated. Similar artefacts recovered from archaeological sites are also reviewed and implications discussed. 相似文献