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41.
The aim of the study was to investigate the hypothesis that consumption of fish liver increases cancer risk in humans due to increased intake of persistent organic pollutants (POPs). This study is based on data from the Norwegian Women and Cancer Study (NOWAC). The study has a prospective cohort design with questionnaire data from 64 285 randomly selected Norwegian women (aged 40-70 at baseline) and linkage to the Norwegian Cancer Registry. Cox proportional hazards regression was used to calculate risk ratios associated with consumption of fish liver and total cancer and cancer in breast, uterus, and colon. Fish liver consumption was, after adjusting for known risk factors, associated with a significant reduced risk for total cancer (RR = 0.92, 95% CI: 0.85, 0.99), and non-significant reduced risk for breast cancer (RR = 0.90, 95% CI: 0.78, 1.04), and colon cancer (RR = 0.82, 95% CI: 0.63, 1.07). Relative risk for uterus cancer was 0.82 (95% CI: 0.61-1.12). No significant dose-response effect was found for frequency of fish liver consumption (when divided into three intake groups) and total cancer, nor for any of the other cancer sites.We have concluded that in Norwegian women, fish liver consumption was not associated with an increased cancer risk in breast, uterus, or colon. In contrast, a decreased risk for total cancer was found.  相似文献   
42.
A questionnaire study was performed among Swedish organic livestock farmers to determine their view of animal welfare and other ethical issues in animal production. The questionnaire was sent to 56.5% of the target group and the response rate was 75.6%. A principal components analysis (exploratory factor analysis) was performed to get a more manageable data set. A matrix of intercorrelations between all pairs of factors was computed. The factors were then entered into a series of multiple regression models to explain five dependent variables. Respondents were well educated and had long experience of farming. 81% were full-time farmers. They generally had a very positive attitude towards organic animal husbandry. They considered allowing animals their natural behavior a central aim, which is in accordance with organic philosophy. Farmers tended to be less approving of concepts like animal rights, dignity, and intrinsic value. When analyzing correlations between the factors, two groups of farmers emerged that were only partially correlated, representing different attitudes and behavioral dispositions. These may be interpreted as two subpopulations of organic livestock farmers in Sweden: those who saw organic farming as a lifestyle (``pioneer attitude') and entrepreneurs, who considered making money and new challenges more important. Their view of animal welfare differed. While the pioneers considered natural behavior a key issue, this was less important to the entrepreneurs, who also had a more approving attitude towards invasive operations such as castration and were more critical of the organic standards.  相似文献   
43.
The major purpose of this paper is to explore the potential value of benefit–cost evaluation for stormwater quality management decisions at a local level. A preliminary benefit–cost analysis (BCA) screening method is used for maximum extent practicable (MEP) analysis, identifying promising management practices, and identifying societal and economic tradeoffs for local stormwater problems. Ballona Creek, a major urban storm drain in Los Angeles, California, USA, is used to illustrate the practicality of the benefit–cost evaluation. The Ballona Creek example demonstrates the economic limits of stormwater management in an urban region and attests to the value of coordinated basinwide management compared to uncoordinated management by individual landowners. Evaluation results suggest that in urban areas, the benefit of stormwater quality improvements might be far greater if accompanied by comprehensive redesign of drainage networks and neighboring land uses. In this case, benefit–cost analysis is found to be useful for evaluating and understanding stormwater management alternatives despite the uncertainties in characterizing stormwater quality and the effects of stormwater management on improving receiving water quality.  相似文献   
44.
Recently the European Council agreed on a CO2 reduction target of 10% by the year 2010. In accordance with this, Denmark decided to reduce its CO2 emissions by 25% over the same time period. One important element of both the European and Danish agreements is energy saving in industries and in private households. Typically industries and private households are also expected to participate in other kinds of environmental improvements, e.g. waste treatment. Such improvements in environmental performances are normally accounted for. In industry, for example, green accounting or environmental auditing are techniques used to measure progress in environmental performance. But when it comes to the environmental performance of people or households very few book-keeping principles have been developed. This paper describes a Danish share-housing project's efforts to formulate an environmental policy and outline an environmental accounting system which can keep track of a household environmental record. It describes the environmental accounting methods, the results and experiences from its first five years.  相似文献   
45.
Antarctic fishes contain large quantities of lipid in adipose tissue, blood and oxidative muscle. In this study, the fatty acyl compositions of free fatty acids (FFA) and triacylglycerol (TAG) in serum, adipose tissue and oxidative muscle were determined in two species of Antarctic fishes, Trematomus newnesi Boulenger, 1902, and Notothenia gibberifrons Lönnberg, 1905, collected off the Antarctic Peninsula in February and March 1987. Total lipid contents of serum and oxidative muscle in each species also were measured. T. newnesi, a mesopelagic species, has significantly more lipid in the serum than N. gibberifrons, a demersal species (17.6±2.4 and 10.4±1.0 mg lipid g-1 serum, respectively). The oxidative muscle of T. newnesi also contains more lipid than does that of N. gibberifrons (12.5 and 9.3% by dry weight, respectively). Fatty acids comprising greater than 5% of one or more of the lipid pools assayed in both species include 14:0, 16:0, 16:1, 16:2, 18:0, 18:1, 20:5 and 22:6. The percentages of 16:1 were lower (p<0.05) in oxidative muscle FFA than in all other assayed lipid pools in both species, suggesting a catabolic preference for some monoenes in oxidative muscle of these fishes. The percentage of 14:0 was two-to three-fold higher in adipose tissue TAG than in all other lipid pools in both species. Differences in fatty acid compositions between lipid pools indicate than proteins involved in the mobilization, transport or catabolism of fatty acids exhibit differential recognition of fatty acids in T. newnesi and N. gibberifrons.  相似文献   
46.
The kinetics and efficiency of sterol production and bioconversion of phytosterols in two heterotrophic protists Oxyrrhis marina and Gyrodinium dominans were examined by feeding them two different algal species (Rhodomonas salina and Dunaliella tertiolecta) differing in sterol profiles. R. salina contains predominantly brassicasterol (?99%) and <2% cholesterol. The major sterols in D. tertiolecta are ergosterol (45–49%), 7-dehydroporiferasterol (29–31%) and fungisterol (21–26%). O. marina fed R. salina metabolized dietary brassicasterol to produce 22-dehydrocholesterol and cholesterol. O. marina fed D. tertiolecta metabolized dietary sterols to produce cholesterol, 22-dehydrocholesterol, brassicasterol and stigmasterol. G. dominans fed either R. salina or D. tertiolecta metabolized dietary sterols to make cholesterol, brassicasterol and a series of unknown sterols. When protists were fed R. salina, which contains cholesterol, the levels of cholesterol were increased to a magnitude of nearly 5- to 30-fold at the phytoplankton-heterotrophic protist interface, equivalent to a production of 172.5 ± 16.2 and 987.7 ± 377.7 ng cholesterol per mg R. salina carbon consumed by O. marina and G. dominans, respectively. When protists were fed D. tertiolecta, which contains no cholesterol, a net production of cholesterol by the protists ranged from 123.2 ± 30.6 to 871.8 ± 130.8 ng per mg algal C consumed. Cholesterol is not only the dominant sterol, but a critical precursor for many physiologically functional biochemicals in higher animal. As intermediates, these heterotrophic protists increase the amount of cholesterol at the phytoplankton–zooplankton interface available to higher trophic levels relative to zooplankton feeding on algae directly.  相似文献   
47.
Are you interested in making the job of complying with federal environmental requirements cheaper and smarter for your business? The U.S. Environmental Protection Agency is committed to helping business and other sectors make more sense of environmental requirements through a number of innovative programs, one of the most far‐reaching being Project XL. © 2000 John Wiley & Sons, Inc.  相似文献   
48.
A wide range of delta morphologies occurs along the fringes of the Young Sound in Northeast Greenland due to spatial heterogeneity of delta regimes. In general, the delta regime is related to catchment and basin characteristics (geology, topography, drainage pattern, sediment availability, and bathymetry), fluvial discharges and associated sediment load, and processes by waves and currents. Main factors steering the Arctic fluvial discharges into the Young Sound are the snow and ice melt and precipitation in the catchment, and extreme events like glacier lake outburst floods (GLOFs). Waves are subordinate and only rework fringes of the delta plain forming sandy bars if the exposure and fetch are optimal. Spatial gradients and variability in driving forces (snow and precipitation) and catchment characteristics (amount of glacier coverage, sediment characteristics) as well as the strong and local influence of GLOFs in a specific catchment impede a simple upscaling of sediment fluxes from individual catchments toward a total sediment flux into the Young Sound.  相似文献   
49.
The need for enhanced environmental planning and management for highland aquatic resources is described and a rationale for integrated action planning is presented. Past action planning initiatives for biodiversity conservation and wetland management are reviewed. A reflective account is given of integrated action planning from five sites in China, India and Vietnam. Eight planning phases are described encompassing: stakeholder assessment and partner selection; rapport building and agreement on collaboration; integrated biodiversity, ecosystem services, livelihoods and policy assessment; problem analysis and target setting; strategic planning; planning and organisation of activities; coordinated implementation and monitoring; evaluation and revised target setting. The scope and targeting of actions are evaluated using the Driving forces, Pressures, State, Impacts and Responses framework and compatibility with biodiversity conservation and socio-economic development objectives are assessed. Criteria to evaluate the quality of planning processes are proposed. Principles for integrated action planning elaborated here should enable stakeholders to formulate plans to reconcile biodiversity conservation with the wise use of wetlands.  相似文献   
50.
Carbon capture and storage (CCS) may become a key technology to limit human-induced global warming, but many uncertainties prevail, including the necessary technological development, costs, legal ramifications, and siting. As such, an important question is the scale of carbon dioxide abatement we require from CCS to meet future climate targets, and whether they appear reasonable. For a number of energy technology and efficiency improvement scenarios, we use a simple climate model to assess the necessary contribution from CCS to ‘fill the gap’ between scenarios’ carbon dioxide emissions levels and the levels needed to meet alternative climate targets. The need for CCS depends on early or delayed action to curb emissions and the characteristics of the assumed energy scenario. To meet a 2.5°C target a large contribution and fast deployment rates for CCS are required. The required deployment rates are much faster than those seen in the deployment of renewable energy technologies as well as nuclear power the last decades, and may not be feasible. This indicates that more contributions are needed from other low-carbon energy technologies and improved energy efficiency, or substitution of coal for gas in the first half of the century. In addition the limited availability of coal and gas by end of the century and resulting limited scope for CCS implies that meeting the 2.5°C target would require significant contributions from one or more of the following options: CCS linked to oil use, biomass energy based CCS (BECCS), and CCS linked to industrial processes.  相似文献   
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