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581.
Determinants of consumer behavior related to organic foods   总被引:1,自引:0,他引:1  
Shepherd R  Magnusson M  Sjödén PO 《Ambio》2005,34(4-5):352-359
There have been many studies of what influences consumers in their decisions to purchase or consume organic foods, mainly concerned with fresh organic foods. These show a discrepancy between attitudes and behavior with people being positive about organic foods but often not purchasing them. This discrepancy seems to be explained by the fact that consumers do not consider "organically produced" to be an important purchase criterion, that organic foods are not perceived to surpass conventional foods regarding taste and shelf life (two qualities rated to be of great importance), and because of the perceived premium prices of organic foods. In two Swedish studies, health benefits were demonstrated to be more strongly related to attitudes and behavior toward organic foods than were perceived environmental benefits. A new European Union (EU) project will investigate the influences on both fresh and processed organic foods and investigate the role of moral, ethical, and affective influences on choice across eight EU countries.  相似文献   
582.
Temporal variations of polycyclic aromatic hydrocarbon (PAH) concentrations in leaves of a Mediterranean evergreen oak, Quercus ilex L., were investigated in order to assess the suitability of this species to biomonitor PAH air contamination. Leaf samples were collected at six sites of the urban area of Naples (Italy) and at a control site in the Vesuvius National Park, in May and September 2001, and in January and May 2002. PAH extraction was conducted by sonication in dichloromethane-acetone and quantification by GC-MS. In winter, leaf total PAH concentrations showed, at all the urban sites, values 2-fold higher than in all the other samplings, reflecting the temporal trend reported for PAH air contamination in the Naples urban area. Moreover, leaf PAH concentrations showed, at all the urban sites, a decrease in May 2002 after the winter accumulation. At the control site leaf PAH concentrations showed lower values and smaller temporal variations than at the urban sites. The findings support the suitability of Q. ilex leaves to monitor temporal variations in PAH contamination. The highest winter concentrations of total PAHs were due to the medium molecular weight PAHs that increased with respect to both low and high molecular weight PAHs. The medium molecular weight PAHs showed the same temporal trend both at the urban and remote sites.  相似文献   
583.
The growing importance of technical regulation affecting the use and sale of chemical products is a topic of interest not only for the chemical industry, but also for governments, nongovernmental organizations, consumers, and interested communities. The results of such regulation on behalf of the environment, health and safety of individuals, as well as its economic effects on industrial activity, are well understood in the United States and recently in the European Union. In less developed countries, however, the general level of public understanding of these issues is still minimal. It is common knowledge that the so-called "regulatory asymmetry" between countries at different levels of development contributes to the establishment of technical barriers to trade. Such asymmetries, however, also have other impacts: the displacement of polluting industrial sectors to countries which have less demanding regulations, the concentration of unsafe and harmful environmental conditions in certain parts of the globe, and the competitive disadvantage for industries located in countries where control is more rigid. This study analyses information on a wide range of technical regulations issued by World Trade Organization (WTO) members, and focuses on those regulations that affect the chemical industry. This information is available through the WTO Enquiry Points, organizations created in each country to administrate the Technical Barriers to Trade Agreement (TBT). This article consists of an analysis of 4,301 notifications of technical regulations by WTO member states in the 7-year period following the establishment of the WTO in 1995. Starting from this mass of information, 585 notifications that affect the circulation or use of chemical products were isolated. Of this group, 71% refer to only 15 countries. This group of notifications was further classified according to their motivation (the environment, health, safety), by the type of product affected (medications, fuels, hazardous products, etc.), by the type of country where it was established (developed, emerging or developing) and the existing conformity assessment mechanism (prohibition, licenses, certification, labeling, etc.). Beyond identifying tendencies in specific industrial sectors, the notifications studied here reach more than 100 chemical products, substances, preparations and other materials, which are subject to various levels of restrictions in different parts of the globe because of their composition or adverse reactions during their life cycles.  相似文献   
584.
The study aimed at verifying a hypothesis that supporting a visual signal of regulation deviation with an auditory one could improve the quality of regulation; the operator would have better information on machine operation. A special simulator was applied to follow-up tracking with a manual lever which controlled vertical movements of a cursor on a monitor screen. Simultaneously with visual information on screen, the operator was provided with an auditory deviation signal of pre-determined characteristics. 33 young males underwent the test. It was found that supporting a visual signal with an auditory one resulted in an improvement in the regulation quality by 5-6%, which proved synergy between those signals. The results may be used in designing tele- and servo-mechanisms, especially for remote control machinery, e.g., inspection robots or micromanipulators controlled by operators in a follow-up system.  相似文献   
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This study was performed to investigate mercury (Hg) tolerance, accumulation, and translocation within the genus Salix for the potential use of this plant to remediate Hg-contaminated sites. Six clones of willow (Salix spp.) were tested on tolerance to Hg by treating plants grown in solution culture with 0 to 15 microM HgCl(2). Results showed that willow had a large variation in its sensitivity to Hg. However, the accumulation and translocation of Hg to shoots was similar in the eight tested willow clones as shown by cold vapor atomic absorption spectrometry analysis when plants were treated with 0.5 microM HgCl(2) in a nutrient solution. The majority of total Hg accumulated was localized to the roots, whereas only 0.45 to 0.62% of the total Hg accumulated via roots was translocated to the shoots. Thus, the root system is the main tissue of willow that accumulates Hg and the majority of the Hg in the root system (80%) was bound in the cell wall.  相似文献   
589.
The results of an assessment study of both industrial and non-industrial dioxin and furan (PCDD/Fs) emissions in the Lombardy Region (Italy) are outlined below. The main data source refer to 1997, and are compiled from the Lombardy Emissions Inventory (developed under the framework of the Regional Air Quality Plan) together with documented emissions factors available. Due to the uncertain nature of the emissions assessment, results are provided as a most probable value within a given range. Total PCDD/Fs emissions in Lombardy average 33 g I-TEQ y(-1), ranging from minimum 13 g I-TEQ y(-1) to maximum 88 g I-TEQ y(-1). The main PCDD/Fs sources are waste incineration, electric arc furnace for steel production, vehicle diesel combustion and residential wood combustion. Incineration emission factors are expected to decrease over the period 2005-2010, in compliance with legal requirements. This will prioritize control over the remaining main PCDD/Fs contributors. Due to limited information available concerning this data, the accuracy of which is uncertain, further research is needed to evaluate the future role of these sources.  相似文献   
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