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Summary While considerable progress has been achieved in understanding and addressing environmental problems over the last 15 years, it is clear that much still remains to be done. Prominent among the concerns calling for further action are the dispersion of toxic substances from a large variety of sources and uses, the accumulating and widespread effects of air pollution, and inefficient management of the natural resource base needed to sustain future economic development. It is increasingly evident that work on these issues must be addressed in their global context, including the developing world.Mr Erik Lykke took up his duties as Director of Environment for the Organisation for Economic Co-operation and Development (OECD) on 5 November, 1984. He is Norwegian, and comes from the Norwegian Ministry of Environment, where he was appointed Director General when it was established in 1972. Before that appointment he held various posts in the Norwegian Ministry of Foreign Affairs and in the Norwegian Foreign Service, and worked in the Norwegian Embassies in Ottawa and London and the Delegation to NATO.Mr Lykke graduated from the University of Oslo in 1954 (MA in political science, history and sociology) and worked for a short time as a journalist. He was assistant to Mr. Trygve Lie (a former Secretary-General of the United Nations) and Foreign Minister Halvard Lange. He has worked on a number of national committees, dealing with space, nuclear research, research in science and technology, air, acid precipitation, and law of the sea and polar matters.From 1970, up to his appointment as OECD Director of Environment, he was closely involved in the development of Norwegian policy and practice on environmental protection and in international work in this field. He was actively engaged in the preparations for the 1972 UN Environment Conference and the 1972 Convention for the Prevention of Marine Pollution by Dumping from Ships and Aircraft (he was the first Chairman of the Oslo Commission). He was also Chairman of the UN-ECE and OECD Environment Committees, and has led Norwegian delegations to a number of international meetings and conferences.The opinions expressed in this paper are those of the author and do not necessarily represent the views of the OECD or of the Governments of its Member countries.  相似文献   
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Objectives

To give an overview of the genetic and structural abnormalities occurring in fetuses with nuchal translucency (NT) measurement exceeding the 95th percentile at first-trimester screening and to investigate which of these abnormalities would be missed if cell-free fetal DNA (cfDNA) were used as a first-tier screening test for chromosomal abnormalities.

Methods

This is a national study including 1901 pregnancies with NT≥95th percentile referred to seven university hospitals in the Netherlands between 1 January 2010 and 1 January 2016. All cases with unknown pregnancy outcome were excluded. Results of detailed ultrasound examinations, karyotyping, genotyping, pregnancy and neonatal outcomes, investigation by a clinical geneticist and post-mortem investigations were collected.

Results

In total, 821 (43%) pregnancies had at least one abnormality. The rate of abnormalities was 21% for fetuses with NT between 95th and 99th percentile and 62% for fetuses with NT≥99th percentile. Prevalence of single-gene disorders, submicroscopic, chromosomal and structural abnormalities was 2%, 2%, 30% and 9%, respectively.

Conclusion

Although cfDNA is superior to the combined test, especially for the detection of trisomy 21, 34% of the congenital abnormalities occurring in fetuses with increased NT may remain undetected in the first trimester of pregnancy, unless cfDNA is used in combination with fetal sonographic assessment, including NT measurement.  相似文献   
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In this paper a method for the study of the qualitative similarity of extractable humic substance (EHS) in marine sediments based on the realisation of UV spectral library of EHS is described. the spectral library was built including the digitised spectra of humic substance extracted from several marine sediments (46 samples) and two samples of standard materials (lignin sulphonate and humic substance) in a Statistica data file. the data matrix was elaborated by means of different multivariate statistic techniques such as Cluster Analysis (CA), Principal Components Analysis (PCA) and the univariate technique Spectral Correlation Analysis (SCA). This approach allows us to show the contribution of different organic compounds (aromatic, lipid and acid) to the composition of EHS and moreover it evidences also the structural characteristics of EHS in terms of similarities in the qualitative composition of samples such as presence of terrestrial and/or vegetal contributions. the UV library is an objective tool to study the qualitative composition of EHS and it represents a complementary approach to the most common methods based on the application of spectroscopic (IR, 13CNMR), potentiometric and chromatographic techniques.  相似文献   
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Industrial energy programs such as energy audit programs and long-term agreements (LTAs) are one of the most common means of promoting energy efficiency in industry. As a result of the European Energy End-Use Efficiency and Energy Services Directive from 2006, the Swedish Government Bill proposed a national energy program towards industrial small- and medium-sized enterprises (SMEs) using more than 500 MWh energy annually. The aim of this paper is to present the structure and design of the program, adopted in 2010, the logics in brief behind the structure, as well as an ex-ante evaluation of the program’s cost-effectiveness. The paper is aimed towards the part of the program involving industry, i.e. not the part involving companies within service and sales etc. The proposed design primarily includes a subsidized energy audit with some minor LTA-elements, such as the need to report results from the energy audit, to present a plan over which measures to conduct, and after three years present which measures that were implemented. The ex-ante evaluation of the program shows a cost-effectiveness of 0.25–0.50 Eurocents/kWh, yielding savings of about 700–1 400 GWh annually.  相似文献   
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