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151.
Consumption rates of marine predators are vital to assessing their trophic impacts and potential consequences of fisheries removal and habitat alteration, yet are rarely estimated. Standard metabolic rates were estimated for juvenile brown stingrays, Dasyatis lata, and used as input parameters for a bioenergetics model to predict consumption rates. Temperature and mass had significant effects on metabolic rates. The energy budget of juvenile brown stingrays was heavily weighted toward metabolism, accounting for 66 % of consumed energy. Growth accounted for 7 % of the energy budget indicating very slow growth potentially due to limited food resources. Population consumption rates suggest potential for strong top-down effects on prey populations due to stingray predation. This study suggests the use of Kāne‘ohe Bay as a nursery habitat for juvenile brown stingrays is a trade-off between increased juvenile survival through predator avoidance and a late age at first maturity due to slow growth rates resulting from low prey availability.  相似文献   
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This paper explores the role that Internet and online technologies played in research dissemination and knowledge mobilization in a recent climate change research project, MC3. In addition, the team looked at the potential of online expert-practitioner research collaborations for these purposes. Electronic communication was seen as a key element for creating distributed networks essential to the project and for building new practitioner/research knowledge collaboratives. The paper discusses how online communication strategies and technologies were used for wide dissemination of its research outcomes. MC3's research dissemination and knowledge mobilization strategies are analyzed, using engagement as the primary measure, to gain insights on the effectiveness and challenges of using Internet-based tools for communicating climate change innovations and actions.  相似文献   
156.
The electrostatic granular filter developed by Combustion Power Company combines a moving-bed filter with an electrostatic grid for high-efficiency collection of particulate. The coulomb charge occurring naturally on particulate from combustion or other processes in which tribocharging occurs is sufficient such that imposition of an electric field substantially enhances mechanical collection in the packed filter. A mathematical model is presented which accounts for the major parameters affecting electrostatic performance. Experimental data developed in an industrial unit retrofitted with electrostatic equipment and a pilot-scale filter demonstrates dramatic improvement in opacity and outlet loading; the industrial unit achieved 99% collection efficiency with less that 4 Iwd (1kPa) pressure drop. Data from the pilot-scale filter has shown that collection of micron-size particulate is especially enhanced with the electric field and has confirmed the 99% overall collection capability demonstrated in the industrial unit. The design of a 420,000 acfm (1200 m3/min) system being installed at Weyerhaeuser Company's Longview, Washington plant is also discussed.  相似文献   
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The complexity of relationships between social change and natural resource management has generated interest in the identification of indicators that might provide more streamlined means for monitoring and planning. In the case of Australia's National Land and Water Resources Audit, interest has focused on the capacity of resource managers to implement more sustainable resource-use practices. This paper reports on an attempt to develop indicators of 'capacity for change' that are statistically reliable and both meaningful and useful to resource managers at a variety of scales. It will be argued, however, that social, spatial and temporal variability in change processes means that no discrete list of social indicators can achieve this task. At the same time that rigorous testing is needed to challenge common-sense assumptions about who is capable of change and where to target capacity-building programmes, data collection and interpretation must be embedded in processes of ongoing negotiation and adaptation among all those involved in, or affected by, resource management.  相似文献   
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This paper presents an evaluation of the long‐term impact of microfinance programmes on Acehnese children during the post‐tsunami recovery. The study, conducted from June to August 2010, examined the impact of microfinance programming six years after the tsunami. The sample consisted of 185 microfinance participants, with a comparison group of 192 individuals who did not participate in microfinance programmes. All respondents were parents, interviewed through a structured survey. The study used four child protection indicators—diet, health, childcare and education—in contrast to traditional repayment rate indicators. The primary results were insignificant with respect to all four child protection indicators, suggesting that, with respect to these indicators, there was no long‐term difference between the impact of microfinance on beneficiaries' children and non‐beneficiaries' children. These findings signify a need for microfinance actors to move beyond traditional indicators of economic success to evaluate the social changes microfinance programmes are presumed to effect.  相似文献   
160.
MR Cull  AJ Dobbs 《Chemosphere》1984,13(9):1085-1089
The results of analyses for polychlorodibenzofuran (PCDF) content in two samples of polychlorobiphenyl (PCB) from used electrical transformers are presented and discussed. In neither sample was there evidence for enhanced PCDF concentrations even though one of them had been subjected to overheating while in service.  相似文献   
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