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Microfossils which are hollow, possess a two-layered vesicle wall, and occur as single elements or, more rarely, as compound forms, have been recovered from the Early Cambrian Heatherdale Shale, on the Fleurieu Peninsula, South Australia. The microfossils, which range in size from 4 to 14.5 μm, are informally and tentatively assigned to the genus Sphaerocongregus Moorman 1974. Superficially they resemble forms assigned to Pyritosphaera Love 1958 and its probable junior synonym, Bavlinella Shepeleva 1962. Topotypes of these genera, however, have yet to be studied using SEM techniques, and their morphologic details remain uncertain. The organic composition of the present microfossils is supported by energy-dispersive X-ray analyses. Samples of the Heatherdale Shale were also analysed using pyrolysis techniques; the organic matter is, however, over-mature with respect to petroleum generation, and no geochemical assessment of original kerogen type is possible.  相似文献   
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During the five years before the outbreak of the First World War, Thomas Graham Brown (1882–1965) conducted research into the control of locomotion that gained him a deserved and long-lasting reputation as a neuroscientist and, in 1927, was recognized by election to the Fellowship of the Royal Society. In 1915, with the First World War raging, he agonized about continuing his research or joining the Royal Army Medical Corps (RAMC). Told by his father to seek a commission, he served two and half years in Macedonia with the British Salonika Force. Whilst in Greece, he kept a daily diary. The entries from June 1916 to May 1917 are extant. They are unpublished and provide the background to the narrative to follow. Casualties with traumatic injury to the brain and spinal cord afforded him the opportunity to carry out careful observations, particularly concerning sensory localization, which resulted in novel findings and his observations on shell shock led to him being called as an expert witness to the national inquiry into the nature and treatment of the condition. In 1920, Graham Brown was appointed to the Chair of Physiology in Cardiff, which he held until 1947.  相似文献   
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This article focuses on the fraught questions surrounding replicas and their use in heritage contexts, drawing on an in-depth qualitative study of a historic replica, the 1970 concrete St John’s Cross, Iona. We examine how replicas ‘work’ and unravel the part that social relations, place, and materiality play in the production and negotiation of their authenticity. The research shows that replicas are important objects in their own right, acquiring value, authenticity, and aura. The ‘life’ of a replica generates networks of relationships between people, places, and things, including the original historic object. While the underlying human stories of creativity, skill, and craftsmanship are rendered invisible when replicas are treated as mere surrogates, we argue that these ‘life-stories’ should be incorporated into future conservation, management and interpretation. The article spells out practical advice and guidance for heritage professionals who find themselves dealing with replicas.  相似文献   
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