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51.
New radiometric data are reported from the recent excavation of the type locality of the Early Upper Palaeolithic entity of the Bohunician. Recently obtained radiocarbon (14C) data on charcoal are compared with new Optically Stimulated Luminescence (OSL) dating of sediment. OSL ages were determined on sediment from the archaeological occupation at Brno-Bohunice, as well as from the over- and underlying loessic sediments. Multiple techniques were applied, which all gave congruent results. While a dual protocol (post IR-OSL) failed the quality criteria tests, ages were obtained by Multiple-Aliquot-Additive-Dose (MAAD) on polymineral material and Single-Aliquot-Regeneration (SAR) on fine grain quartz extract as well as on polymineral material. Fading tests show significant loss of Infrared Stimulated Luminescence (IRSL) after storage for 3 and 12 months for one sample, but little or no fading for others. The resulting (uncorrected) age estimates are smaller than those on quartz by OSL methods. The latter are considered to be more reliable estimates of the sedimentation age of these deposits. The measured OSL doses do not show a simple distribution and the lowest 5% was used for age calculation to represent the most likely sedimentation age. The quartz from the loess overlying the archaeological layer is OSL dated to 30.9 ± 3.1 ka, while the sediment for the paleosol which contains the archaeological layer gave an age of 58.7 ± 5.8 ka. The attribution of this paleosol to the Hengelo interstadial is therefore questionable. However, if the Hengelo interstadial is correlated with the Dansgaard/Oeschger (D/O) event 12, statistical agreement within 2-σ is achieved. The OSL result for the archaeological layer is in accordance with a weighted average TL date on heated flint artifacts of 48.2 ± 1.9 ka from this layer as well as calibrated radiocarbon data (CalPal Hulu 2007) from nearby locations. However, radiocarbon data on charcoal samples obtained during excavation at Brno-Bohunice 2002 provide age estimates between 30 and 40 ka 14C-years, which translate to approximately (33) 35–44 ka on the calendric time scale according to the Hulu 2007 model. For the underlying loess a depositional age of 104.3 ± 10.6 ka was obtained by OSL. The presented OSL ages indicate that a simple correlation of soil sequences between sites within a region has to be verified by chronometric dating.  相似文献   
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The investigation of Lenin's brain by the German neurobiologist Oskar Vogt and his Russian collaborators in Moscow is one of the most exciting and simultaneously questionable chapters in the history of medicine. With the bizarre claim to be able to detect the material substrate of genius it provoked as much unrealistic expectations in the public as strong criticism by the scientific community of brain researchers. The following paper deals in a brief survey with the foundation and the early history of the Moscow Brain Research Institute (INSTITUT MOZGA) and its initial task - the collecting and mapping the brains of famous (Russian) persons in general and the investigation of Lenin's brain in particular.  相似文献   
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When Derek J. de Solla Price studied the growth of science in the 1960s he found a very rapid exponential growth doubling every 15 years. He predicted a logistic slowing down of the growth rate until finally saturation is reached. This study examines three ressource indicators ‐ R&D expenditures, number of professors and of universities ‐ for Germany between 1650 and 2000. They show rather hyperbolic than exponential growth until 1980 when saturation is suddenly reached.  相似文献   
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This paper reports a series of radiocarbon dates on bone samples coming from the Mousterian of Acheulian Tradition (MTA) Layer 3 at the top of the Pech de l'Azé IV (Pech IV, France) Middle Palaeolithic sequence. All of these samples showed evidence of human impact, and they were prepared using current pre-treatment techniques to remove or identify contamination. The results indicate that the MTA at Pech IV started prior to the current limit of radiocarbon calibration (circa 50 ka BP) and ended by 45 ka cal. BP. These dates are supported by additional TL and ESR dates from the sequence, confirm previously suggested correlations between Pech I and IV, and generally fit within the known age range for the MTA. The oldest dates reported here may also lend support to still older TL dates for the MTA that taken together suggest that the MTA extended from late MIS 4 or early OIS 3 through to the end of the Middle Palaeolithic in southwest France.  相似文献   
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