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"Malthusians maintain that rapid population growth aggravates poverty, while Marxists contend that social formations determine its nature and extent. Each perspective is incomplete, however, since it ignores the insights of the other. Latin American states, characterized by dependent capitalism formations and dominated by ruling elites, are generally incapable of solving the problems of population and poverty. Since population growth under dependent capitalism weakens labor's bargaining position against capital, reduced population growth is emphasized as a labor empowerment strategy the poor can implement on their own to improve their socioeconomic conditions." 相似文献
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R. W. Thomas 《Geographical analysis》1990,22(3):209-223
The paper examines the applicability of spatial representation ideas to the determination of equilibrium solutions for multiregion disease models. In particular, alternatives to the standard specification of regionally variable infectivity rates are devised and their impact on the space-time behavior of a carrier model for Hodgkin's disease is assessed using data for Greater Manchester. 相似文献
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Joseph R. Desloges 《The Canadian geographer》1990,34(2):98-109
Changes in the grain-size distribution and the lithologi-cal I mineralogical properties of sandy-gravel sediments are used to discriminate between sources for the alluvial valley-fill of Bella Coola River, coastal British Columbia. Spatially variable bedrock sources, ranging from highly resistant quartz monzonites to easily weathered basalts, yield sediments that reflect parent rock characteristics. Local increases in the D95 fraction of bulk gravel samples and the D50 fraction of sand samples can be related to inputs from steeper, heavily glaciated tributaries, or those underlain by fractured basalts of the Fraser Plateau. Where there are similarities in the grain-size properties of the source and the sampled deposit, however, grain-size information alone cannot be used to discriminate between sources. The lithology of Bella Coola alluvium shows a close correspondence with the general distribution of rock types in the basin, suggesting proportional contributions from most tributary sources over the long term. However, sand samples from the floodplain have a mostly volcanic affinity, indicating the dominance of sediment derived from headwater tributaries underlain by this rock type. Admixture of plutonic source sediments is evident in lower Bella Coola River adjacent to alluvial fans, heavily glaciated tributary creeks or rock walls comprised mainly of quartz monzonite. Les changements dans la granulometrie et les proprietes lithologiques et mineralogiques des sediments de gravel sablonneux servent d differencier les sources des depéts alluviaux de la Riviere Bella Coola sur la céte de la Colombie-Britannique. La variation spatiale des sources fondamentales donnent des sediments qui refletent les caracteristiques de la roche-mbe variant des quartz rnonzonites très résistants aux basaltes superficiellement altérés par les agents atmospheriques. Les augmentations locales dans la fraction D95 des echantillons de gravel et la fraction D50 des echantillons de sable peuvent être reliees la contribution des tributaires aux pentes plus escarpees et fortement glaciaires ou ceux qui traversent les basaltes fractures du Plateau Fraser. Cependant, quand il y a des similitudes dans la granulometrie de la source et le dépôt-échantillon, l'information granulometrique seule ne peut pas 6tre employee pour differencier les sources. La lithologie des alluvions de Bella Coola montre une correspondance avec la distribution générale des types de roches dans le bassin, suggérant des contributions proportionnelles des sources tributaires a long terme. Cependant, les échantillons de sable des plaines sujettes à inondations ont en grande part une affinité volcanique, indiquant que la dominance du sédiment provient des tributaires qui traversent ce type de roche. Une addition de sediments de sources plutonique est evidente dans le bas de la Riviere Bella Coola adjacent aux eventails alluviaux, aux ruisseaux tributaires affect& par une forte glaciation, ou aux murs de roches qui comprennent principalement des quartz monzonites. 相似文献
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Hudson Mark J. Bausch Ilona R. Robbeets Martine Li Tao White J. Alyssa Gilaizeau Linda 《Journal of World Prehistory》2021,34(2):121-158
Journal of World Prehistory - From northern China, millet agriculture spread to Korea and the Maritime Russian Far East by 3500–2700 BC. While the expansion of agricultural societies across... 相似文献
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An increasingly well‐developed body of research uses neighbourhood walks to better understand primary school children's experiences of local environments, yet virtually nothing is known about preschool‐aged children's connections to their neighbourhoods. A reason for this omission is the commonly held view that preschool children lack competency to reflect on lived environments beyond playgrounds, kindergartens, and other confined settings that dominate early childhood. However, preliterate children walk around, use, and create intimate relationships with local environments as shown by 10 children aged 3–5 years from Dunedin in New Zealand during go‐along interviews. We asked each to walk us around their locale, explaining and pointing out favourite and less beloved places and activities. In this article, we advance two arguments: first that preschoolers are knowledgeable meaning makers of place; second that walking with them is a key step to understanding their life worlds and provides a way for preliterate and preverbal children to demonstrate knowledge and understanding of their spatial worlds, including as research participants. We challenge the idea that children of this age lack large‐scale spatial competency and understanding. Walking with them generated an in‐depth appreciation of their experiences of environments and revealed deep connections they had with their locales at varied scales. The work enables us to offer novel insights into spatial competency, sociospatial complexities, and the multiple dimensions of young children's wellbeing affordances in urban environments. Such insights are highly relevant for geographers, planners, and others who shape children's urban environments. 相似文献