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161.
Improved cookstoves have been identified in Mexico as a key opportunity to advance sustainable local development priorities in disadvantaged regions while mitigating climate change. This paper reviews the Patsari Cookstove Project initiated in 2003 by an NGO, Interdisciplinary Group on Appropriate Rural Technology (GIRA). The project applied an interdisciplinary and participative user-centered approach to disseminate improved cookstoves in rural Mexico, with a special focus on indigenous and poor rural communities. To date, GIRA and the Patsari Network have disseminated thousands of stoves using a “training to trainers” model. Benefits from the project include tangible improvements in users’ health, as well as savings in time and money expended on fuelwood procurement and use. The project has also documented substantive environmental benefits from significant mitigation of greenhouse gas (GHG) emissions associated with traditional open fires. To sustain scaling up efforts over the long-term, two networks have been created: The Patsari Network, which includes several organizations promoting Patsari stoves for household users, and the Tsiri Network, which supports local food security and the empowerment of indigenous women through the promotion of institutional cookstoves. Through appropriately designed and implemented local interventions, the project demonstrates that the goals of advancing sustainable local development in rural areas and climate change mitigation may not be contradictory, and may in fact reinforce one another.  相似文献   
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The smart city encompasses a broad range of technological innovations which might be applied to any city for a wide variety of reasons. In this article, I make a distinction between local efforts to reshape the urban landscape, and a global smart city imaginary which those efforts draw upon and help sustain. While attention has been given to the malleability of the smart city concept at this global scale, there remains little effort to interrogate the way that the future is used to sanction specific solutions. Through a critical engagement with smart city marketing materials, industry documents, and consultancy reports, I explore how the future is recruited, rearranged, and represented as a rationalization for technological intervention in the present. This is performed amidst three recurring crises: massive demographic shifts and subsequent resource pressures, global climate change, and the conflicting demands of fiscal austerity that motivate the desire of so many cities to attract foreign direct investment and highly skilled workers. In revealing how crises are pre-empted, precautioned, and prepared for, I argue that the smart city imaginary normalizes a style and scale of response deemed appropriate under liberal capitalism.  相似文献   
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Springs in karstic carbonate rocks frequently carry a sediment load as well as a dissolved load. Analysis of morphology and mineralogy of suspended sediment from three contrasting karst springs reveals a suite of clastic particles that reflect both source areas and processes that take place within the aquifer. Nolte Spring in Lancaster County, Pennsylvania, USA, discharges sediment of apparently precipitated calcite, indicating that at some point in the aquifer or vadose zone, water exceeds saturation with respect to calcite. Sediment morphologies and chemical conditions in the aquifer point to two different scenarios for this precipitation. The other two springs, Arch Spring in Blair County, Pennsylvania and Bushkill Spring in Northampton County, Pennsylvania, show no evidence of calcite precipitation. Arch Spring discharges mainly layer silicates, while Bushkill Spring discharges mainly silica.
Resumen Los manantiales en rocas carbonatadas karstficadas tienen frecuentemente una carga de sedimentos y de sólidos disueltos. Los análisis de la morfología y mineralogía de los sedimentos suspendidos de tres manantiales kársticos contrastados revela un conjunto de partículas clásticas que reflejan ambas áreas fuente y los procesos que tienen lugar dentro del acuífero. Nolte Spring en el Condado de Lancaster, Pennsylvania, USA, descarga sedimento de calcita aparentemente precipitada indicando que en cierto punto del acuífero o en la zona vadosa, el agua supera la saturación con respecto a la calcita. La morfología de los sedimentos y las condiciones químicas en el acuífero apuntan a dos escenarios diferentes para esta precipitación. Los otras dos manantiales, Arch Spring en el Condado de Blair, Pennsylvania y Bushkill Spring en el Condado de Norhtampton, Pennsylvania, no muestran evidencia de precitación de calcita. Arch Spring descarga principalmente filosilicatos mientras que Bushkill Spring descarga fundamentalmente Sílice.

Résumé Les sources situées en contexte carbonaté karstique charrient fréquemment, outre les matières dissoutes, une charge solide. La morphologie et la minéralogie des sédiments en suspension issus de trois sources karstiques de caractéristiques distinctes ont été analysées : une série de particules clastiques, reflétant à la fois les secteurs des sources et les processus internes de l’aquifère, en ressort. Les sédiments issus de Nolte Spring (Comté de Lancaster, Pennsylvanie, Etats-Unis) sont constitués de calcite apparemment précipitée: ceci indique que l’eau atteint la sursaturation vis-à-vis de la calcite à un certain point de l’aquifère ou de la zone non-saturée. La morphologie des sédiments et les conditions chimiques au sein de l’aquifère mènent à deux scénarii différents pour expliquer cette précipitation. Les deux autres sources, Arch Spring (Comté de Blair, Pennsylvanie) et Bushkill Spring (Comté de Northampton, Pennsylvanie), ne présentent aucun indice de précipitation de calcite. Arch Spring exporte essentiellement des phyllosilicates, alors que la silice est majoritaire à Bushkill Spring.
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We find statistically significant correlations in the cosmological matter power spectrum over the full range of observable scales. While the correlations between individual modes are weak, the band-averaged power spectrum shows strong non-trivial correlations. The correlations are significant when the modes in either one or both bands are in the non-linear regime, and approach 100 per cent for pairs of bands in which all the modes are non-linear. The correlations are weaker, but not absent, when computed in redshift space. As estimates of the power spectrum from galaxy surveys require band-averaging, the correlations must be taken into account when comparing a measured power spectrum with theoretical models.  相似文献   
169.
Nutrient distributions across the Porcupine Bank   总被引:1,自引:0,他引:1  
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170.
A simple, unifying approach to classifying quantitatively the susceptibility of catchment soils and surface waters to acidification is suggested. In areas subject to a strong maritime influence, such as the UK and substantial parts of NW Europe, wherever soil mineral weathering rates are low and soils are unfertilised, atmospherically derived base cations of maritime origins have a greater effect than those derived from biogeochemical weathering on the exchangeable soil base cations. This is directly reflected in the relative base cation concentrations of the associated drainage waters, which become increasingly Na-dominated. Using 10 sub-catchments of the River Dee in north-eastern Scotland, it is shown here that the extent of Na dominance, the ratio of Na+ to ΣNa++Ca2++Mg2+, at any point in a river provides a quantitative index of the upstream weathering rate and thus of the susceptibility of the river concerned to acidification under diverse flow conditions. Data from a further 58 sub-catchments from the same river system, and from 4 other catchments from around Scotland, were used to validate this theory.  相似文献   
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