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71.
John Wilson Stewart Fotheringham Gary Hunter Jochen Albrecht 《Transactions in GIS》2006,10(2):153-153
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In spite of raising Asian per capita food production by 27% and making India food self-sufficient, the Green Revolution has received much criticism for its environmental and socio-economic impacts. Taking on board post-development critiques of ‘speaking for’ Third World ‘others’, this paper seeks to examine the Green Revolution from the points of view of people directly affected by it. Comparative, historically-informed research in three villages for which 1972 baseline data exist reveal that the Green Revolution has ensured, in the words of one marginal farmer that ‘nobody sleeps with an empty stomach nowadays’. Most villagers associate the Green Revolution with increases in living standards and weakening community-based wealth hierarchies. Nevertheless, socio-economic inequalities between certain Scheduled Castes and other villagers are still very apparent. 相似文献
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Amy L Wolfe Ran Liu Brian W Stewart Rosemary C Capo David A Dzombak 《Geochemical transactions》2007,8(1):9
Background
Standardized sample preparation techniques allow comparison of pyrite dissolution experiments under diverse conditions. Our objective was to assess dry and wet sieving preparation methodologies, and to develop a reproducible technique that yields uniformly size-distributed material within a limited size range of interest. 相似文献75.
Tsunami deposits in the geological record 总被引:2,自引:0,他引:2
A review is presented here of tsunami deposits in the geological record. It begins with a discussion of the relationships between the processes of tsunami generation and propagation and the sedimentary responses. This is followed by a consideration of the sedimentary processes associated with the passage of tsunami waves across coastlines. Attention is also given to the sedimentary processes associated with tsunami-triggered gravity backwash flows and comparisons are made with turbidity current action. We observe that despite sedimentary evidence for recent tsunamiites, geological research on ancient tsunamis has not identified stratigraphic units associated with onshore tsunami sedimentation. Equally, it is noted that nearly all published studies of sedimentary processes associated with modern tsunamis have not considered patterns of sediment transport and deposition in the offshore zone. 相似文献
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The Sun's magnetic field extends far from the photosphere, into the corona, defining a magnetically dominated region before being drawn out radially by the solar wind flow. This region, where the internal sources of the solar field dominate the plasma structures and the energetic particle movement, can be properly considered the solar magnetosphere. The magnetic field in this region can be approximately described by models that extrapolate photospheric magnetic field observations under some simplifying assumptions. In this paper we use a potential field model which describes the solar field up to a source surface at 3.25 Rs, where the field is constrained to become radial. We present the variation of the magnitude and inclination of the various multipolar components throughout the solar magnetic cycle that characterise the changes in the structure of the solar magnetosphere over a period of 22 years. We also present some 3-D images of the coronal magnetic structure to show the global evolution of the solar magnetosphere throughout the solar cycle and discuss the importance of taking this structure into account in order to relate interplanetary and solar features. 相似文献
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Since 1988, three separate anti-gay rights referenda have been placed on the ballot in the state of Oregon. While in 1988 Oregon voters passed the first measure (subsequently found unconstitutional), they rejected similar referenda in 1992 and 1994. This paper examines the electoral geography of these three referenda both cartographically and quantitatively. It finds patterns of support for the referenda were closely associated with voting patterns for the Republican Party in gubernatorial and presidential elections, and with sociodemographic indicators reflective of traditionalist areas. 相似文献
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Centropages typicus was collected at two hour intervals over a diel cycle at a station near the Chesapeake Bay mouth. The species migrated upward at dusk and downward at dawn. Neither light, temperature, salinity, nor density appeared to cue the migration. Attention is drawn to the need for information on the extent and regularity of migration by individual organisms, and how the lack of such information may lead to poor interpretations of migration data. 相似文献