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This research applies a Bayesian multivariate modeling approach to analyze the spatiotemporal patterns of physical disorder, social disorder, property crime, and violent crime at the small‐area scale. Despite crime and disorder exhibiting similar spatiotemporal patterns, as hypothesized by broken windows and collective efficacy theories, past studies often analyze a single outcome and overlook the correlation structures between multiple crime and disorder types. Accounting for five covariates, the best‐fitting model partitions the residual risk of each crime and disorder type into one spatial shared component, one temporal shared component, and type‐specific spatial, temporal, and space–time components. The shared components capture the underlying spatial pattern and time trend common to all types of crime and disorder. Results show that population size, residential mobility, and the central business district are positively associated with all outcomes. The spatial shared component is found to explain the largest proportion of residual variability for all types of crime and disorder. Spatiotemporal hotspots of crime and disorder are examined to contextualize broken windows theory. Applications of multivariate spatiotemporal modeling with shared components to ecological crime theories and crime prevention policy are discussed.  相似文献   
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Journal of World Prehistory - Neolithic occupation of the Orkney Islands, in the north of Scotland, probably began in the mid fourth millennium cal BC, culminating in a range of settlements,...  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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