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131.
Environmental Science and Pollution Research - The sensitivity of anuran to the effects of habitat destruction and contamination has led to a preoccupying global decline in their populations....  相似文献   
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This paper provides an introduction to the special issue of the Journal of Cleaner Production on “The Sustainability of Seafood Production and Consumption”. The purpose of the special issue is to bring together a series of papers that will form a nucleus for the growth of an emerging area of scholarship. Overfishing and marine habitat damage have generated a global crisis in the production of seafood. In order to respond to this crisis we need systems for the management of seafood production and consumption that will comprehensively reduce and eventually eliminate wastefulness in both capture fisheries and aquaculture systems. Thirteen papers address these issues, with focuses on: seafood harvesting practices, fish processing, life cycle assessment, eco-efficiency, management of wastes, seafood distribution and consumption, total energy costs, eco-labeling, and the conservation of resources and biodiversity. We conclude that major changes are required in our approaches to the management of both the marine environment and our seafood capture and production systems. We also conclude that steps have been taken in this direction, but there is still far to go.  相似文献   
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Social aphid species provide ideal systems to study the ecological influences upon the evolution of sociality because they consist of discrete colonies which are entirely clonal and therefore devoid of any genetic conflict over altruistic behaviour. Although selfishness can be discounted as an obstacle preventing the evolution of altruistic defenders, the vast majority of aphid species are not social. To examine the key life-history and ecological characteristics that interact to facilitate social evolution, we designed a matrix population model based on the natural history of one of the unique aphid species with soldiers, Pemphigus spyrothecae. In addressing the life-history factors, our special interest was to examine the optimal trade-off faced by colonies that can increase their defence investment by producing defenders at birth and/or increasing the duration of the defensive stage. The level and period of exposure to predation and a declining colony birth rate were key factors that selected for social defence. The model demonstrated that, in species which have soldiers that can facultatively develop to make a direct contribution to colony fitness, temporal extension of the soldier stage is a key mechanism of increasing defence investment. This extension is particularly favoured when predation is high and the lifetime of a colony is long. An increase in production of defenders at birth was favoured when mortality due to predation was strongly biased towards defenders. The model suggests that, in species which have the defensive flexibility of choosing whether soldiers remain as such, there is little requirement for flexibility in the morph allocations made at birth. All these predictions were found to be fully compatible with the available empirical data.  相似文献   
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Activities are already underway within the development community to improve climate-change adaptation decision making. In these and related efforts, a focus on building resilience is an important objective, one that resonates with development objectives. Compiling and applying indicators will help development practitioners consider resilience in projects, plans, and decision making. Exactly how to do this is a challenging, but important task. Drawing on diverse methods in the literature, this paper identifies factors important to understanding the evolution of resilience over time and space, and suggests a framework for developing indicators that analysts might select as useful for particular places or sectors. The paper lays the groundwork for an assessment framework that can make future development and adaptation choices more resilient. The framework is intended as a starting point for wider discussions of factors that contribute to building resilience and thus provide the basis to develop a toolkit of metrics and approaches. These discussions will need to bridge research on climate-change adaptation and resilience with practice.  相似文献   
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Meliaceae plant products have been shown to exert pesticidal properties against a variety of insect species. In agricultural pest control programs, such products may have the potential to be used successfully as botanical insecticides. The effect of the neem (Azadirachta indica) limonoids azadirachtin, salannin, deacetylgedunin, gedunin, 17-hydroxyazadiradione and deacetylnimbin on the biology and mortality of rice leaffolder larvae was investigated. In laboratory experiments, treatment with neem limonoids suppressed leaf folding behaviour of C. medinalis. Biological parameters (larval duration, pupal duration adult longevity and fecundity) were also affected by the treatment. Azadirachtin, salannin, and deacetylgedunin showed high bioactivity at all doses, while the rest of the neem limonoids were less active, and were only biologically active at high doses. Azadirachtin was most potent in all experiments and produced almost 100% larval mortality at 1 ppm concentration. These results indicate neem limonoids affect the larval behaviour. These effects are most pronounced in early instars.  相似文献   
138.
Individuals’ relationships to place play an important role in their interactions with their residential environments. Prior research has suggested that neighbourhood satisfaction is closely related to neighbourhood attachment, and that attachment is linked to disaster recovery. This study uses data from a survey of residents of the East Shore neighbourhoods of Staten Island, New York, an area that experienced severe storm surge flooding during Hurricane Sandy, to test the association between neighbourhood satisfaction and self-reported recovery from the storm. Perceived recovery from Sandy is treated as the dependent variable in several ordinal logistic regression models. The key independent variable measure tested is neighbourhood satisfaction rating. A statistically significant direct positive relationship is found between neighbourhood satisfaction and perceived recovery from Sandy. This finding is robust across multiple models with various controls and other covariates. These results suggest that place satisfaction may contribute to disaster recovery.  相似文献   
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Summary In this study of early Chinese scientific thought and practice, the author examines the manner in which Chinese scientific and technical studies related to the rest of their thought, and how this impaired the mathematization of hypotheses about Nature, and therefore, the development of modern science in China. Taking as a starting point his study of the works of Shen Kua (1031–1095), the author, through a thorough-going critique of previous work on the Scientific Revolution problem which exposes its assumptions, fallacies and inadequacies, suggests that the initial heuristic question of the title has served its purpose and considers some of the factors that would need to be explored before a comparative history of scientific development can become a possibility.Dr N. Sivin is Professor of both Chinese Culture and the History of Science at the University of Pennsylvania. Much of the substance of this paper was given at a recent Edward H. Hume Lecture at Yale University.  相似文献   
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