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The article suggests Jobberns’ view of geopolitics ultimately rested on the work of British geographer Sir Halford Mackinder overlain by the writing of American political geographers. Jobberns’ geopolitical thinking was, however, also strongly informed by his being a Freemason. WWII, as the overshadowing external event of Jobberns’ early years at Canterbury, amplified his interest in geopolitics both as a way of understanding the world and, at a time when geography was not universally accepted as a university discipline, as a means of promoting to a wider public the utility of a geographical perspective on world affairs.  相似文献   
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By means of narrow-band Fabry-Perot filters, which exclude the interference from molecular line fluorescence, the brightness of Comet Kohoutek (1973f) has been measured at 8560 and 8748 Å. Data reduction on the basis of averaged Mie-scattering cross sections indicates that the dust production rate was different before and after perihelion at the same heliocentric distances. This asymmetry suggests that vaporization and dust entrainment were governed by fractionation of a multicomponent mixture of parent molecules in a comparatively porous cometary nucleus.  相似文献   
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Résumé Il résulte de l'ensemble des analyses faites que l'eau de la nappe phréatique de l'alluvion ancienne mérite pleinement, au point de vue bactériologique, le qualificatif d'eau potable de très bonne qualité.  相似文献   
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Reducing greenhouse gas emissions from deforestation and forest degradation (REDD) is likely to be central to a post-Kyoto climate change mitigation agreement. As such, identifying conditions and factors that will shape the success or failure of a reduced deforestation scheme will provide important insights for policy planning. Given that protected areas (PAs) are a cornerstone in forest conservation, we draw on interviews and secondary data to analyze the effects of available PA resources, governance ability, the level of community involvement, and provincial deforestation rates on land-cover change in nine PAs in Panama. Our results illustrate that coupling surveillance measures with greater funding and strong governance are paramount to reducing deforestation. Alone, however, these factors are insufficient for forest protection. We argue that conservation approaches that complement effective surveillance with community participation and equitable benefit sharing will address the wider issues of leakage and permanence.  相似文献   
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Forestry is interestingly situated within British imperial networks of the 19th and early 20th centuries whereby India was arguably the main node. Drawing on Lambert and Lester's concept of ‘imperial careering’ as a way of exploring imperial networks, this paper further extends its application to foresters as a group of middle‐level technical experts as well as carrying it into the 20th century when the British Empire was by some measures at its zenith. The forestry careers of Owen Jones and Hugh Corbin, principally in Australia and New Zealand, are used to illustrate the discussion which concludes with some more general observations about imperial careerists.  相似文献   
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We report spatially resolved variations in the 3.4-μm hydrocarbon absorption feature and the 3.3-μm polycyclic aromatic hydrocarbon (PAH) emission band in the Circinus galaxy over the central few arcsec. The absorption is measured towards warm emitting dust associated with Coronal line regions to the east and west of the nucleus. There is an absorption optical depth  τ3.4 μm∼ 0.1  in the core which decreases to the west and increases to the east. This is consistent with increased extinction out to ∼40 pc east of the core, supported by the Coronal emission line intensities which are significantly lower to the east than the west. PAH emission is measured to be symmetrically distributed out to ±4 arcsec, outside the differential extinction region. The asymmetry in the 3.4-μm absorption band reflects that seen in the 9.7-μm silicate absorption band reported by Roche et al., and the ratio of the two absorption depths remains approximately constant across the central regions, with  τ3.4 μm9.7 μm∼ 0.06 ± 0.01  . This indicates well-mixed hydrocarbon and silicate dust populations, with no evidence for significant changes near the nucleus.  相似文献   
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