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51.
/ The Council on Environmental Quality's (CEQ's) principal aims in implementing the National Environmental Policy Act (NEPA) are (1) to reduce paperwork, (2) to avoid delay, and most importantly (3) to produce better decisions that protect, restore, and enhance the environment. This paper presents four strategies for improving the NEPA process along with tools that can be used to implement each strategy. The tools include guidelines for project management and problem definition, tips for acquiring existing information and identifying issues of public concern, worksheets on how to identify and analyze potential impacts on resources, ideas for enhancing NEPA documents, and a NEPA process checklist. The tools can be used at various stages of the NEPA process and provide a toolbox of guidelines and techniques to improve implementation of the NEPA process by focusing the pertinent information for decisionmakers and stakeholders. KEY WORDS: National Environmental Policy Act; NEPA; Environmental impact assessment; Ecosystem management  相似文献   
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Environmental Science and Pollution Research - The current study has assessed whether the oral and/or dermal exposure of C57Bl/6 J mice to tannery effluent (a complex pollutant consisting of...  相似文献   
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An analysis of surface ozone measurements at a west coast site in northern California (Trinidad Head) demonstrates that this location is well situated to sample air entering the west coast of the US from the Pacific Ocean. During the seasonal maximum in the spring, this location regularly observes hourly average ozone mixing ratios 50 ppbv in air that is uninfluenced by the North American continent. Mean daytime values in the spring exceed 40 ppbv. A location in southern California (Channel Islands National Park) demonstrates many of the characteristics during the spring as Trinidad Head in terms of air flow patterns and ozone amounts suggesting that background levels of ozone entering southern California from the Pacific Ocean are similar to those in northern California. Two inland locations (Yreka and Lassen Volcanic National Park) in northern California with surface ozone data records of 20 years or more are more difficult to interpret because of possible influences of local or regional changes. They show differing results for the long-term trend during the spring. The 10-year ozone vertical profile measurements obtained with weekly ozonesondes at Trinidad Head show no significant longer-term change in tropospheric ozone.  相似文献   
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The effects of varying concentrations of landfill leachate on the growth, frond area, chlorophyll content and fluorescence of four strains of Lemna minor were assessed. Growth fluorescence and frond chlorophyll content decreased after seven days exposure to leachate, although responses differed between the strains and end parameters. A L. minor bioassay was used to assess leachate toxicity and the effectiveness of a constructed wetland treatment system and pre-treatment aeration and settlement in reducing toxicity. Pre-treatments were found to significantly reduce toxicity, so their incorporation in any treatment system may increase pollutant stripping.  相似文献   
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Reintroductions are important components of conservation and recovery programs for rare plant species, but their long-term success rates are poorly understood. Previous reviews of plant reintroductions focused on short-term (e.g., ≤3 years) survival and flowering of founder individuals rather than on benchmarks of intergenerational persistence, such as seedling recruitment. However, short-term metrics may obscure outcomes because the unique demographic properties of reintroductions, including small size and unstable stage structure, could create lags in population growth. We used time-to-event analysis on a database of unusually well-monitored and long-term (4–28 years) reintroductions of 27 rare plant species to test whether life-history traits and population characteristics of reintroductions create time-lagged responses in seedling recruitment (i.e., recruitment time lags [RTLs]), an important benchmark of success and indicator of persistence in reintroduced populations. Recruitment time lags were highly variable among reintroductions, ranging from <1 to 17 years after installation. Recruitment patterns matched predictions from life-history theory with short-lived species (fast species) exhibiting consistently shorter and less variable RTLs than long-lived species (slow species). Long RTLs occurred in long-lived herbs, especially in grasslands, whereas short RTLs occurred in short-lived subtropical woody plants and annual herbs. Across plant life histories, as reproductive adult abundance increased, RTLs decreased. Highly variable RTLs were observed in species with multiple reintroduction events, suggesting local processes are just as important as life-history strategy in determining reintroduction outcomes. Time lags in restoration outcomes highlight the need to scale success benchmarks in reintroduction monitoring programs with plant life-history strategies and the unique demographic properties of restored populations. Drawing conclusions on the long-term success of plant reintroduction programs is premature given that demographic processes in species with slow life-histories take decades to unfold.  相似文献   
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An Erratum has been published for this article in Prenatal Diagnosis 22 (5) 2002, 451. Preimplantation genetic diagnosis (PGD) requires the combined efforts of geneticists and workers in the field of reproductive medicine. This was studied on the basis of a questionnaire, sent to 35 members of the PGD Consortium of the European Society of Human Reproduction and Embryology (ESHRE). A reply was obtained from 20 centres. They represent the majority of activities in the field of PGD in the world. It is obvious that many of the activities (in vitro fertilisation, embryo culture and biopsy) take place in IVF units while others (counselling and diagnosis) are the responsibility of genetic diagnostic centres. The distances between both units vary considerably. In all but one centre sex determination is offered. Aneuploidy screening is offered in 13 out of 20 centres. PGD of translocations and other structural chromosome abnormalities is offered in all but one centre. The number of monogenic diseases offered varies considerably. In comparison to prenatal diagnosis PGD is more expensive. The majority of these costs are due to the IVF or ICSI procedure. The charges for PGD vary between about € 600 and € 4000. In 16 out of 20 centres the parents to be must sign an informed consent form. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
59.
We report our experience of 14 preimplantation genetic diagnosis (PGD) cycles in eight couples carrying five different single gene disorders, during the last 18 months. Diagnoses were performed for myotonic dystrophy (DM), cystic fibrosis (CF) [ΔF508 and exon 4 (621+1 G>T)], fragile X and CF simultaneously, and two disorders for which PGD had not been previously attempted, namely neurofibromatosis type 2 (NF2) and Crouzon syndrome. Diagnoses for single gene disorders were carried out on ideally two blastomeres biopsied from Day 3 embryos. A highly polymorphic marker was included in each diagnosis to control against contamination. For the dominant disorders, where possible, linked polymorphisms provided an additional means of determining the genotype of the embryo hence reducing the risk of misdiagnosis due to allele dropout (ADO). Multiplex fluorescent polymerase chain reaction (F-PCR) was used in all cases, followed by fragment analysis and/or single-stranded conformation polymorphism (SSCP) for genotyping. Embryo transfer was performed in 13 cycles resulting in one biochemical pregnancy for CF, three normal deliveries (a twin and a singleton) and one early miscarriage for DM and a singleton for Crouzon syndrome. In each case the untransferred embryos were used to confirm the diagnoses performed on the biopsied cells. The results were concordant in all cases. The inclusion of a polymorphic marker allowed the detection of extraneous DNA contamination in two cells from one case. Knowing the genotype of the contaminating DNA allowed its origin to be traced. All five pregnancies were obtained from embryos in which two blastomeres were biopsied for the diagnosis. Our data demonstrate the successful strategy of using multiplex PCR to simultaneously amplify the mutation site and a polymorphic locus, fluorescent PCR technology to achieve greater sensitivity, and two-cell biopsy to increase the efficiency and success of diagnoses. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
60.
Summary This, The First World Conservation Lecture, was presented at the Royal Institution, London, UK, on 12 March 1981. The Lecture celebrated the 20th anniversary of the World Wildlife Fund, and the first anniversary of the World Conservation Strategy. The Lecture was organized by the World Wildlife Fund, UK.Published with the kind permission of the World Wildlife Fund, UK.Edward Max Nicholson, CB, CVO, Commandeur (Netherlands), Order of the Golden Ark, holds honorary doctorates from the University of Aberdeen, and The Royal College of Art London. He was educated at the University of Oxford, and was a member of the University's expeditions to Greenland (1928) and to British Guiana (1929). He was General Secretary (until 1940), later Chairman of PEP (Political and Economic Planning): now Vice-President of its successor body, the Policy Studies Institute. From 1945 to 1952 he was Secretary of the Office of the Lord President of the Council, then Deputy Prime Minister of the United Kingdom. He was member of the Advisory Council on Scientific Policy from 1948–1964. In 1952 he was leader of the joint UN/FAO Development Team in Baluchistan. Charter Member from 1949, and Director-General (1952–1966) of the Nature Conservancy, London, UK. From 1963 to 1974 he was Convenor of the Conservation Section of the International Council of Scientific Unions' International Biological Programme. President of the IUCN Technical Meeting in Edinburgh in 1956, concerned with rehabilitation of areas biologically devastated by human disturbance, and relation of ecology to landscape planning. Member, Panel on Landscape Action Program, The White House Conference (USA) on Natural Beauty (1965). Secretary, HRH The Duke of Edinburgh's Study Conference on The Countryside in 1970 (1963 and 1965). Council and Board Member of IIED. Godman-Salvin Medallist British Ornithologist Unions. Phillips Medallist and Member of Honour IUCN, Geoffroy St. Hilaire Gold Medal, Société Nationale de Protection de Nature de France, Premio Europeo Cortina-Ulisse (1971), Europa Preis für Landespflege (1972), Hon Member of World Wildlife Fund, Chairman Ecological Parks Trust, President RSPB, 1980. Principal Consultant and Chairman of Land Use Consultants Ltd (London) since 1966. Author of many books,Birds and Men (1951);Britain's Nature Reserves (1958),The System (1967);The Environmental Revolution (1970).  相似文献   
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