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71.
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   
72.
Set in the context of growing concern about the lack of a coherent political response to the economic crisis, and in the aftermath of devastating urban violence in English cities, this paper highlights the pressing need for new forms of political organisation in countries like the UK. The paper focuses on the remarkable growth and prominence of community organising in the UK. The largest community alliance, called London Citizens, now commands significant support and influence in the capital and is attracting attention from politicians, journalists and commentators from across the UK. The rising profile of community organising flies in the face of much scholarship in the social sciences which has long declared the death of geographical community – and its socio-political significance – in the modern metropolis. The paper provides an overview of this literature and highlights the particular importance of population turnover, increased diversity and stretched social networks. In this context, the paper then explores how London Citizens has been able to use a particular geographical architecture to work with and against these challenges. The paper argues that London Citizens’ territorial but institutionally networked structure is particularly important to its growth and impact. This model of politics locates institutional islands of social solidarity and forges connections between them, creating a new community that is able to mitigate some of the effects of population turnover and stretched social networks in the city-at-large. The paper highlights the strengths and weaknesses of this geo-political architecture, drawing attention to the importance of institutional affiliation, identity-making, the reproduction of collective memory, and the issue of funding.  相似文献   
73.
A number of key events in the 1990s have helped shape the decade's cinema. The first of these is the conjuncture of the GATT negotiations (culminating in 1993) and the ascendancy of heritage cinema to mainstream dominance in French production at the expense of popular genres such as comedy and the polar. The second is the attempted return of the auteur through the influential 1994 television series ‘Tous les garçons et les filles de leur âge’. Finally, overlapping to some extent with the return of the auteur, is the arrival of a new generation of film‐makers whose political impact in the call for civil disobedience of February 1997 has undoubtedly affected the way in which the French view the films of this younger generation of directors.  相似文献   
74.
Modern psychosurgery began in 1936 with the work of the Portuguese neurologist, Egas Moniz, who attempted to treat the symptoms of mental illness by severing neural tracts in the frontal lobes. This procedure eventually became widespread and applied to thousands of institutionalized, psychotic patients in the United States and other countries. Despite serious side effects associated with psychosurgery, the apparent importance and validity of the treatment was recognized in 1949 when Moniz received the Nobel Prize for his innovation. Psychosurgery was largely replaced by anti-psychotic drugs in the mid-1950s, and the procedure and its practitioners rapidly fell into disrepute. This article reviews Moniz's career, the factors that led up to his first clinical trials of frontal lobe surgery, and the circumstances that allowed psychosurgery to flourish in the 1940s, eventually leading to Moniz's Nobel Prize.  相似文献   
75.
76.
Most archaeometallurgical studies of iron smelting are based on the analyses of slag fragments randomly selected from slag deposits, and assume that these samples are representative of the typical smelting conditions of the given context. However, little archaeometallurgical research has been published to explore the variability in slag composition within a single smelt, or between individual smelts at the same production site. The material used in this pilot study originates from two iron smelting sites identified in the Buganda Kingdom, Uganda, dated to the 18th and 19th centuries AD. The remains represent evidence of the industrial scale iron production that supported the growth and power of the kingdom. The slag survives in large clusters of complete blocks, in some cases weighing over 100 kg, each resulting from a single smelting episode in a pit furnace. A multi-sample analytical approach has allowed an insight into the compositional diversity within the slag from single smelting events, reflecting changing parameters in the smelting systems. The internal variation of the slag blocks is subsequently compared within and between sites, to address issues of standardisation and to differentiate two technological traditions that would appear very similar at the macroscopic level. On this basis, some sampling recommendations are made for future slag block studies.  相似文献   
77.
We explore the standards of research and reporting needed to justify the destructive analysis of archaeological human bone for biomolecular studies of ancient tuberculosis (TB). Acceptable standards in osteological interpretation have been met in some biomolecular papers, but there are also cases where insufficient care has been taken in distinguishing between pathognomonic lesions and those that are ‘consistent with’ a diagnosis of TB. Some biomolecular studies have failed to recognize that archaeological bones might be contaminated with environmental mycobacteria whose DNA could give rise to false positives in polymerase chain reactions directed at members of the Mycobacterium tuberculosis complex. The difficulties of applying spoligotyping to ancient DNA have also been underestimated and conclusions drawn from such analyses are often weakly supported. Assumptions that mycobacterial DNA preserves better than human DNA, and that contamination with modern DNA is less of a problem, has led in some cases to a laxity in research standards with insufficient attention paid to the need to authenticate ancient DNA results. We illustrate our concerns by reference to a recent paper reporting biomolecular detection of ancient TB DNA in skeletons from the eastern Mediterranean Neolithic settlement of Atlit-Yam. We are unconvinced that the skeletal evidence presented in this paper gives sufficient indication of TB to warrant destructive analysis, and we are concerned that during the biomolecular part of the project inadequate attention was paid to the possibility that results might be due to laboratory cross-contamination or to amplification of environmental mycobacterial DNA present in the bones.  相似文献   
78.
Jane Wills 《对极》2005,37(1):139-159
This paper highlights the importance of organising workers in the low‐paid services sector if British trade unions are to secure themselves for the future. After outlining the scale of the challenge and the new efforts being made to promote organising by unions, the paper looks at the hotel industry in more depth. A case study of a union campaign to win union recognition at the Dorchester Hotel in London is used to highlight the limitations of workplace‐focused campaigns in this sector. Drawing on the lessons of experience in North America, the paper then argues that an extra ‐workplace, occupational and/or sectoral approach may well secure better results. In so doing, workplace issues could be recast as matters of economic and social injustice, widening the scale of any campaign.  相似文献   
79.
80.
This contribution collates information about wrecked slaving vessels discovered or sought by maritime archaeologists since 1972. To date, only a handful of firmly identified, active slave ships have been subject to excavation, but additional work has been carried out on wrecks of former slaver ships and possible slavers. The impending 200th anniversaries of the abolition of the British and US slave trades (2007 and 2008, respectively) appear to have stimulated a new wave of interest in slaver wrecks, and these new initiatives are also discussed.  相似文献   
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