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Searching, gathering, organizing, and retrieving data are basic tasks for historians. As long as historians work by themselves, decisions concerning data format, data exchange, computer platform, and the like remain secondary. Teams of historians often use relational databases for centralized data storage. However, fundamental risks are implicit when one uses databases. Among technical considerations, the process of transformation between the source and the database is a deciding factor. For those who gather data, the effective use of such possibilities as data exchange, compatibility, and simplicity of survey and the reuse of the data in other contexts and platforms becomes increasingly important. In contrast, the user's needs include the possibility of data verification and use of the data for more than one question. Many relational databases have considerable shortcomings because the stored data lose the visual characteristics, the syntax, and the semantics of the original source. The EuroClimHist database environment is a part of the NCCR Climate project. It uses a data tool, written in Java for the gathering of documentary data, which generates extensible markup language (XML) files for data exchange.  相似文献   
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Abstract

In this article, the author presents a strategy for designing relational databases with the program FileMaker Pro (FileMaker) to study the histories of individuals and organizations. The approach facilitates efficiency in inputting data and flexibility for constructing statistical analyses from the raw data. The key feature of the strategy is to define the basic unit of observation in the database in terms of an agent, an event, and a date. Given that programs such as FileMaker can easily sort data by agent and date, once one structures the data correctly, he or she can construct well-ordered event histories for agents, even if the researcher enters the data in an unordered fashion. By using events that happened to an agent at a particular time as the basic unit of observation, one maintains maximum flexibility to do statistical analysis that aggregates basic data in different ways. This article illustrates the power of the approach by outlining ways to analyze changes in geographic distances between two events marking the life histories of chemists.  相似文献   
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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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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   
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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   
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