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Anne-Marie P. Tosolini David J. Cantrill Jane E. Francis 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):366-391
The Paleocene flora from Seymour Island, Antarctica, is one of the most diverse floras of this age in the Southern Hemisphere. First collected on the Swedish South Polar Expedition (1901–1903), it was described by Dusén in 1908 as having 87 leaf taxa. Forty-seven angiosperm taxa were described and/or illustrated. Many species are based on single specimens, and the flora has not been re-examined in its entirety since it was first described. This study is the first reassessment of the flora updating the original research using current methodologies, and permitting evaluation of the flora in the context of modern ideas on plant evolution and palaeogeography. This paper continues the revision of the material first studied by Dusén; a previous paper described the ferns and gymnosperms; here we describe the angiosperms. The revision is based on the original collections held at the Swedish Museum of Natural History, together with the first major new collections held at the British Antarctic Survey. Among the taxa recognized by Dusén, we recognize only three entire-margined and 11 tooth-margined angiosperms. This revision to 14 species notably lacks the two tropical elements originally described from the flora, Mollinedia seymourensis and Miconiiphyllum austral. Hence, its status as a ‘Mixed Flora’ comes into question and influences climatic interpretations based on Gondwanan floras. Anne-Marie Tosolini? [a.tosolini@unimelb.edu.au], Department of Earth Sciences, University of Leeds, Leeds LS2 9JT, UK, and Environmental Geoscience, Latrobe University, Victoria, 3086, Australia; David Cantrill [david.cantrill@rbg.vic.gov.au], National Herbarium of Victoria, Royal Botanic Gardens Melbourne, Private Bag 2000, Birdwood Ave, South Yarra, Victoria, 3141, Australia; Jane Francis [j.francis@earth.leeds.ac.uk], Department of Earth Sciences, University of Leeds, Leeds LS2 9JT, UK. ?Present address: School of Earth Sciences, The University of Melbourne, Victoria 3010, Australia. Received 5.5.2012; revised 13.12.2012; accepted 7.1.2012. 相似文献
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Francis Schiller 《Journal of the history of the neurosciences》2013,22(4):392-401
Since antiquity yawning has attracted a moderate interest among philosophers, psychologists, physiologists, as well as educators, moralists and physicians. Organisms from birds to men and from the womb to the deathbed were found to be displaying it. While sometimes satisfying to the producer, its display is offensive to the lay observer. Hippocrates had it on his lists of useful ‘natures.’ Aristotle dropped a few words on the matter. Boerhaave elevated its function to the intellect of animals. Haller has commented on its relation to the acoustic system, blood-flow, and baby sleep. Darwin mentioned it in connection with emotional behavior. Some modem authors praised its beneficial effects on respiration and smell. In the 1960s, Ashley Montagu tried to correct the contemporary failure to explain the behavior by the fact of raised CO 2 and arterial compression. It also interested some neurologists, especially in its association with the encephalitis lethargica in the 1920s, with ‘spasmodic yawning,’ with epilepsy, not to speak of hysteria. As to boredom or its stimulus, a 40-page dissertation survives from the court of Frederick the Great of the 18th century condemning idleness, a subject that also inspired Blaise Pascal and William James. But in the Hindu world, public yawning was a religious offense. 相似文献
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This paper reports on a study of victimization, offending and fear among homeless young people in Newcastle upon Tyne, England, which employed a participatory methodology. These young people live in marginal and often invisible spaces, yet are subject to a high degree of regulation which structures their experiences of risk. Their accounts demonstrate that an ‘either/or’ distinction which often structures understanding of offenders and victims, feared and fearful, and safe and dangerous spaces has led to their experiences being poorly represented. Homeless young people are often multiply positioned in relation to crime, an understanding which challenges the current political climate in Britain. 相似文献
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