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Kirkfeldt Trine Skovgaard Hansen Anne Merrild Olesen Pernille Mortensen Lucia Hristova Kameliya Welsch Alexander 《Regional Environmental Change》2017,17(3):725-737
Regional Environmental Change - The Arctic Region is characterised by vulnerable ecosystems and residing indigenous people, dependent on nature for subsistence fishing and hunting. The Arctic also... 相似文献
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Sustainable Aquaculture: Are We Getting There? Ethical Perspectives on Salmon Farming 总被引:1,自引:0,他引:1
Ingrid Olesen Anne Ingeborg Myhr G. Kristin Rosendal 《Journal of Agricultural and Environmental Ethics》2011,24(4):381-408
Aquaculture is the fastest growing animal producing sector in the world and is expected to play an important role in global
food supply. Along with this growth, concerns have been raised about the environmental effects of escapees and pollution,
fish welfare, and consumer health as well as the use of marine resources for producing fish feed. In this paper we present
some of the major challenges salmon farming is facing today. We discuss issues of relevance to how to ensure sustainability,
by focusing on animal production systems, breeding approaches, sources for feed ingredients, and genetic engineering strategies.
Other crucial issues such as animal welfare, environmental quality, and ethics are elaborated with regard to relevance for
the sustainability of aquaculture. Additionally, we comment on socio-economic distributive implications by intellectual property
rights (IPR) strategies on access to genetic material and traceability. To improve sustainability of salmon farming we suggest
that there is a need for new approaches to guide research, for identification of ethical issues, and for engaging stakeholders
in resolving these challenges. 相似文献
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We assessed the discriminatory efficiency and cost-effectiveness of a novel way of organising first trimester screening for Down syndrome (DS), contingent testing, where a serological test (PAPP-A and β-hCG: the double test) is made in early first trimester and followed by nuchal translucency testing (NT) only in women with an intermediate risk, e.g. <1:65 and >1:1000, and not in all women as in normal first trimester screening (NFTS). Using Monte Carlo simulation contingent testing had a detection rate (DR) of 78.9% and a false-positive rate (FPR) of 4.0% for DS with 19.4% of women offered NT testing. The DR of NFTS was 85.5% and the FPR 4.4%. The decrease in NT screening was associated with an increase from 23% to 29% in the proportion of DS cases born. The cost of the contingent testing programme was £53 000 per DS case not born and £91 000 in NFTS. The number of aborted fetuses per DS case were 0.35 and 0.36, respectively. Thus, contingent testing is an organisation of first trimester screening where costs can be reduced with a marginal decrease in performance. Contingent testing is attractive in areas where NT screening is the bottleneck preventing the introduction of first trimester screening. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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In order to elucidate the consistency between generally used age-dependent risk values for Down syndrome (DS) and estimates of the probability of miscarriage in Down pregnancies we have compared expected numbers with estimated numbers of births with DS in Denmark had no intervention at all been carried out. The expected numbers were calculated from the distribution of newborn children according to maternal age combined with the age-related risk of DS. The estimated numbers of children that actually would have been born without any intervention were estimated from observed numbers of cases of DS, i.e. the cases born plus – with corrections because of the high probability of miscarriage in DS pregnancies – a proportion of those cases discovered prenatally. The analysis was carried out separately for mothers aged 35 years or older and for younger mothers. We found a high degree of compatibility between expected and estimated numbers, probably with a minor underestimation of the expected values for the older mothers. The performance of DS screening in Denmark in the period under consideration (1980–1998) is discussed in relation to the figures presented. Despite the fact that 11.8% of all pregnancies were subjected to an invasive diagnostic procedure, only about 38% of all births with DS were prevented. This means that in the period 1990–1998, reluctance to accept serological screening has indirectly resulted in the birth of almost 300 cases of DS in Denmark and at the same time the miscarriage of an unreasonable high number of normal fetuses. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Stephen J. Leisz Kjeld Rasmussen Jørgen E. Olesen Tran Duc Vien Bo Elberling Lars Christiansen 《Regional Environmental Change》2007,7(4):187-208
The northern mountain region of Vietnam (NMR) is dominated by swidden/fallow farming systems. The fallow land of these systems is populated by small trees and bushes. Since the 1960s the government of Vietnam has tried to limit or stop swiddening and replace it with permanent upland agricultural fields, paddy, fruit trees and animal husbandry. Discussion in the policy debate and literature focuses on the impacts these changes have on local people’s livelihoods. There have been no attempts to evaluate the impact of these changes on greenhouse gas (GHG) emissions. This paper examines the realities of current farming system changes taking place at the hamlet level and other changes that could take place due to government land use policies and extension programs. The paper answers the following questions: How could farming system changes influence net GHGs? Which farming system changes in the NMR, the trajectories of changes that are currently observed or those that would be followed if farmers adhere strictly to government policies and programs, will have a greater affect on the GHG contributions from agriculture in the region? Could ‘clean development mechanism’ (CDM) projects make a difference in the profitability of the pathways mentioned? Results show: (1) if farming systems in the NMR continue along currently observed change trajectories there will be increases in GHG emissions; (2) if the NMR farming systems change according to government policies and programs there will be a net sequestration of carbon in regrowing vegetation during the initial 20 years; (3) over the longer term, in areas where systems change to fit government policies, increased GHG emissions from other changes in the farming systems (e.g. increased paddy and increased pig raising in sties) will overtake the amounts of carbon sequestered in vegetation; (4) CMD projects only make a difference if (a) maximum biomass potential of regrowing fallow can be reached; (b) a favourable baseline is chosen; (c) timing and length of the accounting period is correct; and (d) farmers do not take compensatory action in response to government policies. Given these conditions it does not appear that currently envisioned clean development mechanisms would be beneficial to farmers in the NMR. 相似文献
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Severin Olesen Larsen Karen R. Wøjdemann Anne-Cathrine Shalmi Karin Sundberg Michael Christiansen Ann Tabor 《黑龙江环境通报》2002,22(13):1207-1208
The influence of fetal gender on the level in the first trimester of the serological markers alpha-fetoprotein (AFP), pregnancy-associated plasma protein-A (PAPP-A) and free beta human chorionic gonadotropin (βhCG) and on nuchal translucency is described for 2637 singleton pregnancies with normal outcome. Mean log MoM values for pregnancies with female and male fetuses were calculated using regression of log marker values on gestational age expressed as crown rump length and on maternal weight. A pronounced gender impact was found for free βhCG, being 16% higher for female than for male fetuses. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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