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961.
Capps and Lederman, in a paper published in this journal in 2015, argued that, at the time, the dismal circumstances of the Ebola outbreak in West Africa was an opportunity to revisit public health responses to emergent infectious diseases. Using a One Health lens, they argued for an ecological perspective—one that looked to respond to zoonoses as an environmental as well as public health concern. Using Ebola virus disease as an example, they suggested shared immunity as a strategy to vaccinate both humans and great apes. Since then, vaccination as a conservation strategy in this case has been debated and at least one great ape vaccination trial has been proposed: some, however, are less convinced of the ethical arguments to pursue vaccinating wild animals. Using this opportunity, we review Capps and Lederman’s arguments and directly respond to the plausible objections to them.  相似文献   
962.
963.
The focus of this paper is on normative ethical theories and endangered species. To be exact, I examine two theories: the theory of obligation and care ethics, and ask which is better-suited in the case of endangered species. I argue that the aretic, feminist-inspired ethics of care is well-suited in the case of companion animals, but ill-suited in the case of endangered species, especially in the case of “unlovable” species. My argument presupposes that (1) we now live an era where human disturbances to planetary ecosystems are triggering a sixth mass species extinction, and (2) widespread interventions will be needed to save many species from extinction.  相似文献   
964.
EGR is one of the most significant strategies for reducing especially nitrogen oxides (NOx) emissions from internal combustion engines. The thermal efficiency of spark ignition engines is lower than compression ignition engines because of its lower compression ratio. If the compression ratio is increased to obtain higher thermal efficiency, there may be a knocking tendency in spark ignition engines. EGR can be used in order to reduce NOx emissions and avoid knocking phenomena at higher compression ratios. In-cylinder temperature at the end of combustion is decreased and heat capacity of fresh charge is increased when EGR applied. Besides EGR, spark timing is another significant parameter for reducing exhaust emissions such as nitrogen oxides, and unburned hydrocarbon (UHC). In this study the effects of EGR and spark timing on spark ignition engine were investigated numerically. KIVA codes were used in order to model combustion process. The combustion process has been modeled for a single cylinder, four stroke and gasoline direct injection (GDI) spark ignition engine. The results showed that in-cylinder pressure and heat release rate decrease as EGR ratio increase. In-cylinder pressure increases with the advancing of spark timing. Advancing spark timing increases the heat release rate and in-cylinder temperature. The simulation results also showed that EGR reduced exhaust gas temperature and NOx emissions.  相似文献   
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966.
967.
In the scientific literature, few valuations of biodiversity and ecosystem services following the impacts of toxicity are available, hampered by the lack of ecotoxicological documentation. Here, tributyltin is used to conduct a contingent valuation study as well as cost–benefit analysis (CBA) of measures for improving the environmental status in Swedish coastal waters of the Baltic Sea. Benefits considering different dimensions when assessing environmental status are highlighted and a quantitative environmental assessment framework based on available technology, ecological conditions, and economic valuation methodology is developed. Two scenarios are used in the valuation study: (a) achieving good environmental status by 2020 in accordance with EU legislation (USD 119 household−1 year−1) and (b) achieving visible improvements by 2100 due to natural degradation (USD 108 household−1 year−1) during 8 years. The later scenario was used to illustrate an application of the assessment framework. The CBA results indicate that both scenarios might generate a welfare improvement.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0682-4) contains supplementary material, which is available to authorized users.  相似文献   
968.
969.
Intensifying global trade will result in increased numbers of plant pest and pathogen species inadvertently being transported along with cargo. This paper examines current mechanisms for prevention and management of potential introductions of forest insect pests and pathogens in the European Union (EU). Current European legislation has not been found sufficient in preventing invasion, establishment and spread of pest and pathogen species within the EU. Costs associated with future invasions are difficult to estimate but past invasions have led to negative economic impacts in the invaded country. The challenge is combining free trade and free movement of products (within the EU) with protection against invasive pests and pathogens. Public awareness may mobilise the public for prevention and detection of potential invasions and, simultaneously, increase support for eradication and control measures. We recommend focus on commodities in addition to pathways, an approach within the EU using a centralised response unit and, critically, to engage the general public in the battle against establishment and spread of these harmful pests and pathogens.  相似文献   
970.
There is a growing demand for alternatives to Sweden’s current dominant silvicultural system, driven by a desire to raise biomass production, meet environmental goals and mitigate climate change. However, moving towards diversified forest management that deviates from well established silvicultural practices carries many uncertainties and risks. Adaptive management is often suggested as an effective means of managing in the context of such complexities. Yet there has been scepticism over its appropriateness in cases characterised by large spatial extents, extended temporal scales and complex land ownership—characteristics typical of Swedish forestry. Drawing on published research, including a new paradigm for adaptive management, we indicate how common pitfalls can be avoided during implementation. We indicate the investment, infrastructure, and considerations necessary to benefit from adaptive management. In doing so, we show how this approach could offer a pragmatic operational model for managing the uncertainties, risks and obstacles associated with new silvicultural systems and the challenges facing Swedish forestry.  相似文献   
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