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During recent reinvestigations in the Great Cave of Niah in Borneo, the ‘Hell Trench’ sedimentary sequence seen by earlier excavators was re-exposed. Early excavations here yielded the earliest anatomically-modern human remains in island Southeast Asia. Calibrated radiocarbon dates, pollen, algal microfossils, palynofacies, granulometry and geochemistry of the ‘Hell Trench’ sequence provide information about environmental and vegetational changes, elements of geomorphic history and information about human activity. The ‘Hell’ sediments were laid down episodically in an ephemeral stream or pool. The pollen suggests cyclically changing vegetation with forest habitats alternating with more open environments; indicating that phases with both temperatures and precipitation reduced compared with the present. These events can be correlated with global climate change sequences to produce a provisional dating framework. During some forest phases, high counts of Justicia, a plant which today colonises recently burnt forest areas, point to fire in the landscape. This may be evidence for biomass burning by humans, presumably to maintain forest-edge habitats. There is evidence from palynofacies for fire on the cave floor in the ‘Hell’ area. Since the area sampled is beyond the limit of plant growth, this is evidence for human activity. The first such evidence is during an episode with significant grassland indicators, suggesting that people may have reached the site during a climatic phase characterised by relatively open habitats ∼50 ka. Thereafter, people were able to maintain a relatively consistent presence at Niah. The human use of the ‘Hell’ area seems to have intensified through time, probably because changes in the local hydrological regime made the area dryer and more suitable for human use. 相似文献
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Ipek O¨zbek So¨nmez 《European Planning Studies》2007,15(3):319-338
In Turkey, poverty has been a main subject of debates since 1960s. It used to be a serious problem for both rural areas and the big cities that gained migration. In Turkey and world-wide since the 1980s, however, there have been more research interests in the concentrated urban poverty, especially along with the increase in levels of impoverishment around the world. With the help of a case study in Izmir (Turkey), this paper aims to examine the process of concentrated urban poverty from different points of view in the literature. This is a case study developed at the peripheries of the traditional city centre—or inner areas—of the city of Izmir, Turkey. The paper, first, discusses the parameters of concentrated poverty according to the literature. Then it introduces the study findings of the author, which point out the macro-scale, micro-scale and ecological dynamics that are important in the development of concentrated urban poverty. The macro-scale dynamics suggest that poverty in inner areas of the city are related to the unbalanced development trends within the country, such as the overgrowth of metropolitan cities, economic restructuring processes, migration trends and the development of informal economy. The ecological dynamics address to the housing and job location preferences and invasion-succession processes in the city, which emphasize that socio-economic characteristics of inner areas of the city are different from those of other city parts. Micro-scale dynamics are related to poors' ability of developing solidarity relations among themselves, which is also related to the spatial characteristics of inner areas of the city, according to this study's findings. 相似文献
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Gross CG 《Journal of the history of the neurosciences》2007,16(3):320-331
In 1870 Gustav Fritsch and Edvard Hitzig showed that electrical stimulation of the cerebral cortex of a dog produced movements. This was a crucial event in the development of modern neuroscience because it was the first good experimental evidence for a) cerebral cortex involvement in motor function, b) the electrical excitability of the cortex, c) topographic representation in the brain, and d) localization of function in different regions of the cerebral cortex. This paper discusses their experiment and some developments in the previous two centuries that led to it including the ideas of Thomas Willis and Emanuel Swedenborg, the widespread interest in electricity and the localizations of function of Franz Joseph Gall, John Hughlings Jackson, and Paul Broca. We also consider the subsequent study of the motor cortex by David Ferrier and others. 相似文献
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M. Ma G. Dong X. Liu E. Lightfoot F. Chen H. Wang H. Li M. K. Jones 《International Journal of Osteoarchaeology》2015,25(6):923-934
Intercontinental exchanges between communities living in different parts of Eurasia during the late prehistoric period have become increasingly popular as a topic of archaeological research. The Qijia culture, found in northwest China, is one of the key archaeological cultures that can shed light on trans‐Eurasian exchange because a variety of imports are found in this cultural context. These imports include new cereals and animals, which suggest that human diets may also have changed compared with previous periods. To understand human and animal diets of the Qijia culture, carbon and nitrogen isotope ratios from human and animal skeletal remains were analysed from the type site of the Qijia culture at Qijiaping. The results demonstrate that human diet at the site mainly consisted of millet and animals fed on millet. C3 cereals, such as wheat and barley, did not contribute significantly to human diet, and no isotopic differences were found between adult and subadult diets. Furthermore, three outlying human results raise the possibility of exogenous individuals, perhaps in relation to the parallel movement of animals, crops and goods. This study provides human and animal dietary information for evaluating the nature of exchange and diffusion in eastern Eurasia at this time. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献