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Claims of employment and productivity gains from environmental taxation are examined in the context of recent policy developments which have extended the traditional role of economic instruments in environmental regulation. Although the general existence of such spin-offs cannot be established, the debate has clarified guidelines for designing and implementing specific environmentally based taxes to help deliver sustainable development. Recent UK tax proposals have started to draw on the flexibility of fiscal instruments to tackle environmental problems. Innovations include earmarking taxes to fund allied spatial and sectoral programmes, recycling revenues to provide fiscally neutral improvements in tax efficiency and using taxation to help promote eco-efficiency.  相似文献   
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Fetal sacrococcygeal teratoma can lead to a high output cardiac failure resulting in hydrops fetalis. One of the prenatal therapeutic options is to occlude the feeding vessels by radiofrequency ablation. We present a case of fetal sacrococcygeal teratoma diagnosed at 13 weeks of gestation. The tumour increased in size more than 100-fold over 5 weeks causing polyhydramnios and cardiac and placental enlargement. Thermocoagulation was performed at 18 weeks' gestation by passing an insulated electric wire through an 18-gauge needle placed close to the feeding vessels of the tumour at its neck. Blood supply to the tumour was successfully reduced. However, fetal death was diagnosed 2 days after the procedure. We speculate that it may be safer to limit the extent of coagulation in one attempt but to repeat the procedure at a later stage when necessary. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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Our massive tampering with the world's interdependent web of life-coupled with the environmental damage inflicted by deforestation, species loss, and climate change-could trigger widespread adverse effects, including unpredictable collapses of critical biological systems whose interactions and dynamics we only imperfectly understand. Uncertainty over the extent of these effects cannot excuse complacency or delay in facing the threats ... We the undersigned, senior members of the world's scientific community, hereby warn all humanity of what lies ahead. A great change in our stewardship of the earth and the life on it is required, if vast human misery is to be avoided and our global home on this planet is not to be irretrievably mutilated. (Union of Concerned Scientists, 1992)  相似文献   
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Assessing the impact of global changes and protection effectiveness is a key step in monitoring marine fishes. Most traditional census methods are demanding or destructive. Nondisturbing and nonlethal approaches based on video and environmental DNA are alternatives to underwater visual census or fishing. However, their ability to detect multiple biodiversity factors beyond traditional taxonomic diversity is still unknown. For bony fishes and elasmobranchs, we compared the performance of eDNA metabarcoding and long-term remote video to assess species’ phylogenetic and functional diversity. We used 10 eDNA samples from 30 L of water each and 25 hr of underwater videos over 4 days on Malpelo Island (pacific coast of Colombia), a remote marine protected area. Metabarcoding of eDNA detected 66% more molecular operational taxonomic units (MOTUs) than species on video. We found 66 and 43 functional entities with a single eDNA marker and videos, respectively, and higher functional richness for eDNA than videos. Despite gaps in genetic reference databases, eDNA also detected a higher fish phylogenetic diversity than videos; accumulation curves showed how 1 eDNA transect detected as much phylogenetic diversity as 25 hr of video. Environmental DNA metabarcoding can be used to affordably, efficiently, and accurately census biodiversity factors in marine systems. Although taxonomic assignments are still limited by species coverage in genetic reference databases, use of MOTUs highlights the potential of eDNA metabarcoding once reference databases have expanded.  相似文献   
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This investigation consisted of a questionnaire survey of the graduate selection methods used by 536 organizations in the U.K. The use of application forms for pre-selection purposes was widespread, although only a minority of organizations appeared to have approached this task in a systematic way. While references were also widely used, they were often taken up very late in the selection process, and only a minority of organizations sought specific information about job related abilities from referees. Interviews were universally used, both on their own, and as a component of an assessment centre. A total of 44 per cent of organizations used assessment centres as part of graduate recruitment. For most of those organizations using assessment centres, the interview was reported as being the most important component of the centre in determining final selection decisions. Most organizations provided some training for their selectors but this was typically general in nature, rather than being specific to graduate recruitment. The results are discussed in terms of their implications, both for practical application, and for future research.  相似文献   
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