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Particulate matter (PM) has become a major research issue receiving increasing attention because of its significant negative impact on human health. There are main indicators that next to the morphological characteristics of the particle, also the chemical composition plays an important role in the adverse health effects of PM. In this context, the rather polar organic fraction of PM is expected to play a major role, and advanced analytical techniques are developed to improve the knowledge on the molecular composition of this fraction. One component class that deserves major attention consists of the oxygenated polycyclic aromatic hydrocarbons (PAHs). Those compounds are considered to be among the key compounds in PM toxicity. This paper presents a comprehensive review focusing on the analysis, fate and behavior of oxygenated PAHs in the atmosphere. The first part of the paper briefly introduces (i) the main sources and atmospheric pathways of oxygenated PAHs, (ii) available physical–chemical properties and (iii) their health effects. The second and main part of this paper gives a thorough discussion on the entire analytical sequence necessary to identify and quantify oxygenated PAHs on atmospheric PM. Special attention is given to critical parameters and innovations related to (i) sampling, (ii) sample preparation including both extraction and clean-up, and (iii) separation and detection. Third, the state-of-the-art knowledge about the atmospheric occurrence of oxygenated PAHs is discussed, including an extended overview of reported concentrations presented as a function of sampling season and geographical location. A clear seasonal effect is observed with the median of the oxygenated PAHs concentrations during winter being a factor of 3–4 higher than during summer. However, the oxygenated PAH/parent PAH ratio is about 20 times higher during summer, indicating the importance of photochemical activity in the atmosphere.  相似文献   
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There is a science‐practice gap in organizational behavior (OB) whereby entire bodies of scholarly knowledge are ignored by practitioners. We identify research needed to improve performance management practices that is likely to enhance the relevance of OB in the eyes of practitioners and thus help reduce the science‐practice gap. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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Environmental Economics and Policy Studies - Money can be understood from an individual perspective as an abstract form of wealth. From a communal perspective, however, money is better regarded as...  相似文献   
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Harnessing the economic potential of the oceans is key to combating poverty, enhancing food security, and strengthening economies. But the concomitant risk of intensified resource extraction to migratory species is worrying given these species contribute to important ecological processes, often underpin alternative livelihoods, and are mostly already threatened. We thus sought to quantify the potential conflict between key economic activities (5 fisheries and hydrocarbon exploitation) and sea turtle migration corridors in a region with rapid economic development: southern and eastern Africa. We satellite tracked the movement of 20 loggerhead (Caretta caretta) and 14 leatherback (Dermochelys coriacea) turtles during their postnesting migrations. We used movement‐based kernel density estimation to identify migration corridors for each species. We overlaid these corridors on maps of the distribution and intensity of economic activities, quantified the extent of overlap and threat posed by each activity on each species, and compared the effects of activities. These results were compared with annual bycatch rates in the respective fisheries. Both species’ 3 corridors overlapped most with longline fishing, but the effect was worse for leatherbacks: their bycatch rates of approximately 1500/year were substantial relative to the regional population size of <100 nesting females/annum. This bycatch rate is likely slowing population growth. Artisanal fisheries may be of greater concern for loggerheads than for leatherbacks, but the population appears to be withstanding the high bycatch rates because it is increasing exponentially. The hydrocarbon industry currently has a moderately low impact on both species, but mining in key areas (e.g., Southern Mozambique) may undermine >50 years of conservation, potentially affecting >80% of loggerheads, 33% of the (critically endangered) leatherbacks, and their nesting beaches. We support establishing blue economies (i.e., generating wealth from the ocean), but oceans need to be carefully zoned and responsibly managed in both space and time to achieve economic (resource extraction), ecological (conservation, maintenance of processes), and social (maintenance of alternative livelihood opportunities, alleviate poverty) objectives.  相似文献   
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