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David H. Kaplan 《Journal of Cultural Geography》2015,32(1):23-39
Since the late nineteenth century, France has been a destination for people outside its borders. In recent decades, most immigrants have come from outside of Europe, often from ex-colonies in Northern Africa, West Africa, and Indochina. The Parisian area has welcomed a disproportionate share of these immigrants and neighborhoods have been shaped and reshaped to reflect their presence. This paper examines three neighborhoods in Paris—Belleville, the Triangle de Choisy, and the Goutte d'Or—which are each composed of and shaped by separate ethnic populations. To a great extent, these neighborhoods are imprinted by commercial activity, often involving customers who come from well outside the neighborhood and networks that extend beyond the nation. They also show patterns of multiethnicity which allows for difference between groups to be maintained, even as the space shared between them is effectively negotiated. 相似文献
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Fluid mixing induced by hydrothermal activity in the ordovician carbonates in Tarim Basin,China
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Permian hydrothermal activity in the Tarim Basin may have been responsible for the invasion of hot brines into Ordovician carbonate reservoirs. Studies have been undertaken to explain the origin and geochemical characteristics of the diagenetic fluid present during this hydrothermal event although there is no consensus on it. We present a genetic model resulting from the study of δ13C, δ18O, δ34S, and 87Sr/86Sr isotope values and fluid inclusions (FIs) from fracture‐ and vug‐filling calcite, saddle dolomite, fluorite, barite, quartz, and anhydrite from Ordovician outcrops in northwest (NW) Tarim Basin and subsurface cores in Central Tarim Basin. The presence of hydrothermal fluid was confirmed by minerals with fluid inclusion homogenization temperatures being >10°C higher than the paleo‐formation burial temperatures both in the NW Tarim and in the Central Tarim areas. The mixing of hot (>200°C), high‐salinity (>24 wt% NaCl), 87Sr‐rich (up to 0.7104) hydrothermal fluid with cool (60–100°C), low‐salinity (0 to 3.5 wt% NaCl), also 87Sr‐rich (up to 0.7010) meteoric water in the Ordovician unit was supported by the salinity of fluid inclusions, and δ13C, δ18O, and 87Sr/86Sr isotopic values of the diagenetic minerals. Up‐migrated hydrothermal fluids from the deeper Cambrian strata may have contributed to the hot brine with high sulfate concentrations which promoted thermochemical sulfate reduction (TSR) in the Ordovician, resulting in the formation of 12C‐rich (δ13C as low as ?13.8‰) calcite and 34S‐rich (δ34S values from 21.4‰ to 29.7‰) H2S, pyrite, and elemental sulfur. Hydrothermal fluid mixing with fresh water in Ordovician strata in Tarim Basin was facilitated by deep‐seated faults and up‐reaching faults due to the pervasive Permian magmatic activity. Collectively, fluid mixing, hydrothermal dolomitization, TSR, and faulting may have locally dissolved the host carbonates and increased the reservoir porosity and permeability, which has significant implications for hydrocarbon exploration. 相似文献
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In this paper, we argue that place mapping is useful for approaching children's conception of place and that this is of relevance when designing physical activity interventions. We contend that socio-material factors influence children's perception and use of places, and are crucial to understand in relation to their use of local neighbourhoods for physical activity. A place mapping of children's understandings and everyday use of their local neighbourhood in suburban Copenhagen was conducted with a fifth grade elementary school class. The mapping and subsequent analysis resulted in three categories of relevance to children's conceptions of place; located social experiences, experiences of the unknown, and children's contested spaces. We argue that such knowledge can provide useful information in the development and evaluation of activities that promote physical activity in urban spaces. 相似文献
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Latent trajectory models for space‐time analysis: An application in deciphering spatial panel data
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Li An Ming‐Hsiang Tsou Brian H. Spitzberg Dipak K. Gupta J. Mark Gawron 《Geographical analysis》2016,48(3):314-336
This article introduces latent trajectory models (LTMs), an approach often employed in social sciences to handle longitudinal data, to the arena of GIScience, particularly space‐time analysis. Using the space‐time data collected at county level for the whole United States through webpage search on the keyword “climate change,” we show that LTMs, when combined with eigenvector filtering of spatial dependence in data, are very useful in unveiling temporal trends hidden in such data: the webpage‐data derived popularity measure for climate change has been increasing from December 2011 to March 2013, but the increase rate has been slowing down. In addition, LTMs help reveal potential mechanisms behind observed space‐time trajectories through linking the webpage‐data derived popularity measure about climate change to a set of socio‐demographic covariates. Our analysis shows that controlling for population density, greater drought exposure, higher percent of people who are 16 years old or above, and higher household income are positively predictive of the trajectory slopes. Higher percentages of Republicans and number of hot days in summer are negatively related to the trajectory slopes. Implications of these results are examined, concluding with consideration of the potential utility of LTMs in space‐time analysis and more generally in GIScience. 相似文献
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SENIOR MIGRATION: SPATIAL CONSIDERATIONS OF AMENITY AND HEALTH ACCESS DRIVERS* 总被引:1,自引:0,他引:1
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This paper extends the literature on amenity migration by focusing on healthcare access for later‐life migrants. Previous studies have strongly suggested that natural amenities are strong pull factors for later‐life migrants, but high natural amenity counties rarely possess the quality healthcare access optimal for elderly migrants. Utilizing a spatial Bayesian estimation strategy, we explicitly consider numerous drivers of later‐life migration to examine the extent to which health access is a driver in location decisions. We find healthcare access measures, including hospital expenditures, hospital beds, and number of doctors, are positively associated with later‐life migration decisions. 相似文献