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681.
O. Tully  V. O'Donovan  D. Fletcher 《Marine Biology》2000,137(5-6):1031-1040
 The accumulation of lipofuscin, which is an indictor of physiological age, in the brain of juvenile European lobster (Homarus gammarus L.) was monitored for 22 mo in three experimental temperature regimes that simulated seasonal variation in temperature in the geographic range of this species. Metabolic rate responses to changes in temperature were estimated by measuring the activity of the electron transport system (ETS) in muscle tissue and in vivo rates of oxygen consumption. Lipofuscin accumulation oscillated with simulated seasonal changes in temperature and was described by seasonalised von Bertalanffy growth functions. The incremental accumulation in lipofuscin between sampling dates was linearly related to the number of degree days that accumulated between dates, irrespective of the amplitude of temperature fluctuation that had occurred. ETS activity increased with acclimation temperature and was modelled using a polynomial function. This indicated a lower temperature sensitivity in the temperature mid-range (12 to 16 °C), although the Q10 for this mid-range was 2.1. ETS activity in lobsters acclimated to 8 and 18 °C and assayed at 13 °C was similar, indicating no compensation for changes in environmental temperature. Oxygen consumption rate was significantly higher at 14 °C than at 10.5 °C and had a Q10 of 3.6, again suggesting no compensation to temperature change. The absence of metabolic compensation in response to temperature change in H. gammarus is consistent with the predictability of changes in temperature and food availability in the sub-littoral environment of this species. As lipofuscin accumulates according to metabolic rate, and metabolic rate in H. gammarus is directly correlated with temperature, geographic differences and long-term temporal trends in temperature will need to be considered when converting physiological age indices, obtained from lipofuscin estimates, to a chronological scale. Received: 27 April 2000 / Accepted: 21 July 2000  相似文献   
682.
683.
Bakewell O 《Disasters》2000,24(2):103-116
This paper draws on a study of Angolan refugees in Zambia to suggest ways that the perspectives and interests of the local population can be included in the assessment of relief interventions. Taking an actor-oriented approach, the paper suggests stepping back from the categorisation of the situation as an emergency and particular groups of people as the beneficiaries. Such categories are imposed from outside and may not reflect local people's outlook on the situation. In the case of Angolans in Zambia, the category of refugees had dissolved in the border villages to the extent that it was practically impossible to distinguish between refugees and hosts. This was in contrast to the official settlements where people were marked out as refugees and the label was maintained and reproduced over many years. Investigating outcomes in the border villagers in terms of refugees and the refugee problem would have been futile. The paper calls for evaluations of humanitarian assistance in complex emergencies to look beyond the 'beneficiaries' and to investigate the wider context of 'normality'. Neglecting the life and world of local people will make it impossible to understand the process by which external interventions are mediated at the local level to give particular outcomes, and valuable lessons which could help alleviate suffering will be lost.  相似文献   
684.
Environmental Science and Pollution Research - In the indoor environment of dental clinics, dental personnel and patients are exposed to a risk of infection because of the transmission of...  相似文献   
685.
Major mining companies have recently embraced the sustainable development paradigm, in seeking to improve their competitiveness and increase shareholder returns. Successful mine closure is one important element of this process. Improved performance in this area is essential if surrounding communities are to see mining companies as responsible corporate and social partners.
In Indonesia, the new approach has coincided with the development of specific mine closure legislation. To facilitate the legislation, a consortium of mining companies joined to form the Industry Mine Closure Steering Committee. This Committee has lobbied the Government, actively negotiating to incorporate sustainable development ideals and practices into the new legislation. The Committee's aim has been to foster continued development of the mining industry, while taking account of variation in environmental, social and community conditions. In describing the process, this article seeks to provide guidance for the development of mine closure legislation in other nations.  相似文献   
686.
The overall objective of this research was to develop and test a method of determining emission rates of volatile organic compounds (VOCs) and other gases from soil surfaces. Soil vapor clusters (SVCs) were designed as a low dead volume, robust sampling system to obtain vertically resolved profiles of soil gas contaminant concentrations in the near surface zone. The concentration profiles, when combined with a mathematical model of porous media mass transport, were used to calculate the contaminant flux from the soil surface. Initial experiments were conducted using a mesoscale soil remediation system under a range of experimental conditions. Helium was used as a tracer and trichloroethene was used as a model VOC. Flux estimations using the SVCs were within 25% of independent surface flux estimates and were comparable to measurements made using a surface isolation flux chamber (SIFC). In addition, method detection limits for the SVC were an order of magnitude lower than detection limits with the SIFC. Field trials, conducted with the SVCs at a bioventing site, indicated that the SVC method could be easily used in the field to estimate fugitive VOC emission rates. Major advantages of the SVC method were its low detection limits, lack of required auxiliary equipment, and ability to obtain real-time estimates of fugitive VOC emission rates.  相似文献   
687.
Environmental Science and Pollution Research - Air particulate matter exposure has been linked to cardiovascular and atherosclerosis as a result of increase oxidative stress and inflammatory...  相似文献   
688.
Environmental Science and Pollution Research - A real industrial effluent from the pre-treatment and painting processes was polished through adsorption using alternative biochar derived from grape...  相似文献   
689.
Environmental Science and Pollution Research - Sustainable desalination can be achieved by adopting renewable energy-based low-cost and low-impact desalting techniques. In this investigation,...  相似文献   
690.
Russian Journal of Ecology - Responses to contamination of several soil types with crude oil were comparatively analyzed in organisms of different trophic groups. Samples of soddy podzolic, light...  相似文献   
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