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221.
Hominins living in southern India 74,000 years ago faced a deteriorating environment, as the global climate moved from interglacial into full glacial conditions. At the same time, South Asian populations witnessed the widespread deposition of tephra from the Sumatran Toba super-eruption, the largest explosive volcanic event of the past two million years. Here we report new data on the lithic technology and environmental context for a southern Indian site with hominin occupation in association with Toba tephra deposits: Jwalapuram Locality 3 in the Jurreru Valley. Sedimentological and isotopic studies demonstrate that a cooling trend was in effect in this part of southern India prior to the eruption, and that thick deposits of ash in the Jurreru Valley supported grassland communities before more wooded conditions were re-established. Detailed technological analyses of an expanded lithic sample from Locality 3 suggest cultural continuity after the eruptive event, and comparisons with lithic core technologies elsewhere indicate that Homo sapiens cannot be ruled out as the creator of these Middle Palaeolithic assemblages.  相似文献   
222.
Discovery of pigments at Middle Palaeolithic sites is of interest in the context of the ongoing debate about the tempo and mode of the emergence of modern human behaviour. Here we analyse four previously undescribed fragments of pigmental material from Es-Skhul shelter, layer B, Israel, McCown excavations, identified at the Department of Palaeontology, Natural History Museum, London. One of them is still partially embedded in the hard breccia characteristic of this layer. Inspection of breccia fragments from layer B has led to the identification of small pieces of red and orange pigmental material still enclosed in large clasts, further corroborating the attribution of the larger pieces analysed in this study to layer B. The four objects are studied using optical microscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray (EDX), X-ray micro-diffraction (μ-XRD), Particle-Induced X-Ray Emission Spectrometry (PIXE), and Proton-Induced Gamma-ray Emission (PIGE). The specimens display various hues of yellow, orange, red, and one of them presents a gradual variation of shade from yellow to dark orange. SEM/EDX analysis identifies two specimens (Skhul 1 and 2) as being composed of iron-rich calcium phosphate, the third (Skhul 3) of potassium-rich clay with titanium-rich iron oxide inclusions, and the fourth (Skhul 4) of pure iron oxide crystals. TEM/EDX and μ-XRD analysis demonstrate that three pieces (Skhul 1, 2 and 4) were heated to at least 300 °C, a process that has partially or completely dehydrated goethite into haematite and changed their pristine yellow colour into orange or red. Skhul 3 shows no sign of heating, suggesting that its haematite content has a geological origin. The different mineral composition of the pieces suggests that they must come from a variety of sources. This implies that the associated collection strategies included the selection of materials that differed not only with respect to colour but also with respect to other physical and chemical properties. Although no formal proof exists that these lumps of pigmental material were deliberately heated, results obtained are consistent with this explanation.  相似文献   
223.
都市年轻人     
Chris 《世界》2010,(5):156-159
每个人的梦想车都不尽相同,对一个年轻人来说,选择这个级别的车型作为梦想,也是需要相当的勇气和个性的,触手可及的价格,一见倾心的外形,空间?要它干吗?  相似文献   
224.
Chris 《世界》2010,(1):170-173
继PORSCHE Panamera于日前正式引入国内后,2010款911 Turbo敞篷版也以亚洲首发的身份于广州车展亮相,并且将于2010年初正式在国内上市销售.2010款PORSCHE 911 Turbo搭载全新3.8L涡轮增压引擎。最大输出功率可达368KW。  相似文献   
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226.
In this study, we analyse the three-dimensional micromorphology of cut marks on fossil mammal remains from a ∼0.5 million year old Acheulean butchery site at Boxgrove (West Sussex, southern England), and make comparisons with cut marks inflicted during the experimental butchery of a roe deer (Capreolus caproelus) using a replica handaxe. Morphological attributes of the cut marks were measured using an Alicona imaging microscope, a novel optical technique that generates three-dimensional virtual reconstructions of surface features. The study shows that high-resolution measurements of cut marks can shed light on aspects of butchery techniques, tool use and the behavioural repertoire of Lower Palaeolithic hominins. Differences between the experimental cut marks and those on the Boxgrove large mammal bones suggest variation in the angle of the cuts and greater forces used in the butchery of the larger (rhinoceros-sized) carcasses at Boxgrove. Tool-edge characteristics may account for some of these differences, but the greater robusticity of the Boxgrove hominins (attributed to Homo heidelbergensis) may be a factor in the greater forces indicated by some of the cut marks on the Boxgrove specimens.  相似文献   
227.
In 1894 at St. Vincent's Hospital Melbourne, George Adlington Syme removed a meningioma from a patient with symptomatic focal epilepsy. The operation stands as the first surgery based on seizure localization in Australia. It is also the country's first documented successful resection of an intracranial meningioma. It followed William Macewen's landmark cerebral localization case on the boy John McKinley by 18 years and Victor Horsley's first epilepsy case on Hughlings Jackson's patient James B. by a mere 8 years. Syme's patient, Constable John G., survived the operation by some 23 years, dying from a gunshot wound to the head in 1917. Newly discovered inquest papers reveal that the coroner's judgment that the death was accidental completely fails to address the more credible scenario of suicide. The story makes for a fascinating epilogue to an important landmark in Australia's neurosurgical history.  相似文献   
228.
229.
据说,前往西班牙度假的时候,范思哲发现了属于他的色彩—红。阿玛尼则热衷于带着一群年轻人大玩游艇跳水。他说,与年轻人一起度假能让自己变得活力充沛,富于创造力。年复一年,大大小小的设计师都会在大大小小的发布会上推出自己的度假系列,诸如海洋主题、丛林主题、沙漠主题、都市主题等等,他们先是跟着灵感去旅行,然后从旅途中获得快乐,以及灵感。我们常被这样的灵感打动和怂恿,立即开始计划自己的旅行,因为无法抗拒其中传达的自由和激情;也因为,假期比现实更接近梦想中的生活——悠闲的、自由的、轻松的、快乐的、完美无缺、随心所欲。  相似文献   
230.
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