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This article presents and discusses the chronological layout of the final Mousterian and Uluzzian levels of Fumane Cave in northern Italy using 14C, ESR and TL methods. Given its complex sedimentary and cultural succession, Fumane is a key site to assess the Middle–Upper Palaeolithic transition in Southern Europe and to explore Neanderthal behaviour and to compare it with the first Aurignacians. Large ranges defined by the ESR and TL dates cover the radiocarbon ages for units from A11 to A4, respectively, from 42.8 to 32.5 ka BP become progressively younger in agreement with the stratigraphy, despite high dispersions within the same unit. Our estimates using chronometric data seem to support the hypothesis that the sequence may cover almost 10,000 radiocarbon yr and that from comparison with the sedimentological and palaeoecological data, the late Middle Palaeolithic and the early Upper Palaeolithic at Fumane occur in sediments formed under moderately cool to mild climatic conditions correlated to the Hengelo-Interstadial, shifting towards cooler and drier conditions. Finally, comparisons between the Fumane data set and other sites in the North-Adriatic region are discussed.  相似文献   
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Australia contains some of the world's richest and apparently longest traditions of rock pictographs. Dating this art, however, has been problematic, with few ‘direct’ and reliable dates of Pleistocene or early Holocene age having been obtained from visible, representational imagery. This paper critically reviews the evidence for the antiquity of pigment rock art in Australia by examining the various dating techniques employed. The accurate and reliable dating of rock art worldwide is crucial to understanding the evolution of modern human symbolism and whether cognitive modernism came about after, rather than with, the first signs of full biological modernism; understanding the pitfalls and devising proper methods are crucial prerequisites. Towards these ends, this paper reviews the results and techniques that have been employed to date the apparently earliest known pictographs in Australia.  相似文献   
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Optimization models for the design of regional air quality control strategies have been developed under the assumption that the annual frequencies of the different meteorological conditions remain constant from year to year. This paper demonstrates empirically that this assumption is not correct, and that the solutions of such models lead either to violation of the annual air quality standard or to unnecessarily high costs for pollution abatement. A chance-constrained, geographically based approach is formulated to account for the interannual randomness of the meteorological conditions and for the locations of pollution sources and receptors and is applied with different approximation methods. The policy implications of the results in terms of optimal standard selection and implementation of the optimal chance-constrained pollution abatement plan through decentralized decision-making by individual pollution sources are assessed.  相似文献   
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For decades zooarchaeological studies mainly focused on teeth age profiles to derive central hypotheses concerning human subsistence during the Pleistocene. Behavior was often related to hunting and/or scavenging strategies according to two models: attritional versus catastrophic. However, few studies have estimated basic demographic parameters using standard methods of population ecology, which are necessary for a more confident interpretation of animal paleopopulation structures. Thanks to a remarkably rich fossil bone assemblage from the Upper Pleistocene cave of Geula (Mount Carmel, Israel), in this paper we perform a paleodemographic analysis of Hystrix refossa, Gervais 1852 (Mammalia, Rodentia). We first consider phylogenetic and morphometric dental criteria for the comparison of Pleistocene porcupine species, followed by an examination of taphonomic conditions of the bone assemblage. We focus strongly on the age structure of the fossil population, presenting a new methodological approach that combines life tables and Leslie matrix models – one of the best-known methods in population ecology for assessing population growth and age distribution. We detail demographic parameters derived from cross-sectional life tables and past trends in the porcupine population at Geula Cave using simple matrix projection model. Finally, we were able to perform an elasticity analysis to identify which demographic component was potentially the most critical for influencing growth. We show that the population of H. refossa did not decline or shrink but was stable. Our results permit us to characterize Geula Cave as a natural shelter for porcupines, with limited evidence to scavenging and hunting by either hyenas or humans.  相似文献   
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The Lower Paleolithic sites of Ambrona and Torralba (Soria, Spain) are often associated with each other because of their proximity although they do not represent the same morphostratigraphic unit. Systematic and extensive excavations were conducted at these sites by an American team during the 1960s and 1980s. Recently (1989–2000), a Spanish team has reactivated the research by initiating a new interdisciplinary project. In the central sector and west of the Ambrona site a stratigraphy has been established with six units from AS1 at the base to AS6 at the surface, corresponding to fluvial–lacustrine deposits in which abundant fauna associated with Acheulian artefacts were found. The most abundant species were elephant, horse, deer and aurochs. Other species like carnivores occur in small numbers only. The lithic assemblage is relatively sparse and consists of a few bifaces, choppers and several flake tools distributed throughout levels AS1 to AS5. The fauna and the lithic industry therefore document human presence at Ambrona during the Middle Pleistocene. In order to verify the presumed antiquity of the Ambrona deposits, horse teeth sampled in levels AS1, AS2 and AS6 were analysed using combined ESR/U-series (US) methods. The samples from the lower levels (AS1 and AS2) underwent a very recent uranium uptake as indicated by the U-series dates, ranging between 5 and 18 ka. In contrast, a more conventional postmortem uranium uptake was observed in the upper level samples (AS6) in the enamel and dentine tissues, while a light U-leaching was observed in the cementum. The combined ESR/U-series dates obtained on these samples suggest a minimum age of approximately 350 ka, contemporaneous of OSI 9 or the end of OSI 11, for the Ambrona site.  相似文献   
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We report new archaeological excavations from northern Australia revealing part of a charcoal design likely to be c. 28,000 years old (and chrono-stratigraphically constrained within the period 15,600–45,600 cal BP) on a small rock slab fallen from the ceiling at the rockshelter of Nawarla Gabarnmang in Jawoyn country, Arnhem Land. This represents the oldest confirmed pictograph in Australia.  相似文献   
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Regional telecommunication flows, measured in terms of numbers of messages and conversation minutes, are analyzed with a systematic random sample of toll calls characterized by their timing, duration, cost, and origin-destination (O-D) locations. Point-to-point models are econometrically estimated, with such independent variables as destination market size, O-D distance, and average and time-of-day (TOD) prices, for the residential and business sectors separately. The results indicate that (1) the demands for calls and conversation minutes are price-inelastic and slightly elastic, respectively, (2) business demand is relatively more price-elastic than residential demand, (3) distance is a strong determinant of telephone demand, and (4) most TOD demand substitutions resulting from TOD price changes would take place between the daily and evening rate periods. Several areas for further research are outlined.  相似文献   
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