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The measures undertaken for reducing the impact of POPs on the environment are discussed in international conventions concerned with these substances and are related to the reporting of obligations which should ensure the control of their implementation and verify the effects of these measures on the environment. An essential element of this reporting involves the data concerning the emissions and environmental impact of these substances in emission inventories. A summary of the current status of emission inventories for POPs with a special focus on atmospheric emissions under EMEP is also presented. There are considerable uncertainties of reported emission data by the individual countries and in expert evaluations regarding marine and atmospheric impacts. Harmonized instruments for emission evaluation are required and under development in the form of guidance documents for the marine environment in ‘Harmonized Quantification and Reporting Procedures for Hazardous Substances (HARP-HAZ)’ and under EMEP in the ‘Atmospheric Emission Inventory Guidebook for UNECE/LRTAP’. The problems and the reasons for uncertainties in the quantification of environmental impacts are presented using the example of lindanes (hexachlorocyclohexane, HCH), polychlorinated biphenyls (PCB), polycyclic aromatic hydrocarbons (PAH) und hexachlorobenzene (HCB).  相似文献   
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The Labyrinthulomycota are a relatively poorly studied group of heterotrophic unicellular eukaryotes. They comprise three lineages, labyrinthulids, thraustochytrids, and aplanochytrids, which are all primarily marine organisms and considered to be important components of marine microbial communities. Recently a number of Labyrinthulomycota have been implicated as parasites of marine (but also terrestrial) plants and marine molluscs. Here we describe a new species of thraustochytrid, Thraustochytrium caudivorum sp. nov. that we have isolated from laboratory cultures of Macrostomum lignano (Rhabditophora, Macrostomorpha), a marine free-living flatworm. In these worms T. caudivorum can cause lesions, which start at the tip of the tail plate and which can lead to the dissolution of the posterior part of the animal. Although the worms can frequently cure these lesions and regenerate the lost parts, the lesions can also result in the complete dissolution of the animal. We describe this thraustochytrid based on pure agar cultures and infestations in the worm cultures. Moreover, we describe its pathological effects on the worms and its morphology using both light and electron microscopy. In addition, we report a phylogenetic analysis using a partial 18S rDNA sequence that allows us to place this new species within the thraustochytrids. Finally, we outline a protocol that allows to permanently remove the parasites from infested worm cultures. We conclude that thraustochytrids represent a novel group of parasites of free-living flatworms. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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In contrast to other apes, humans have relatively greater amounts of armpit hair, which is thought to retain signaling molecules. Although armpit shaving is widespread cross-culturally, its effect on body odor has been little investigated. In four experiments, we tested the effect of shaving and the subsequent regrowth of axillary hair. Armpit odors were collected from men who regularly shaved (group S) or who had never shaved (group N) their armpits before. The samples were subsequently rated by women for intensity, pleasantness, and attractiveness. In Experiments I, II (group N) and III, subjects firstly shaved one armpit and then let the hair regrow over 6 or 10 weeks. In Experiments I, II (group S) and IV, subjects shaved both armpits before the sampling and subsequently shaved one armpit during the same period, leaving the second armpit unshaved. Odors of the shaved armpits were rated more pleasant, attractive, and less intense compared to the unshaved armpits (Experiment I (group N)). However, no significant differences found in Experiments II and III (group N) suggest the effect of shaving is relatively minor. Moreover, there were no significant differences in odor comparing unshaved armpits with armpits after 1 week of regrowth (Experiments I, II (group N) and III) or comparing regularly shaved armpits with armpits after 1 or 3 weeks of regrowth (Experiments I, II (group S) and IV). The odor of shaved armpits was rated significantly more attractive compared to the armpits where hair had been regrowing for 6 or 10 weeks.  相似文献   
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The concentrations of lead in the femura (Pb-F) and the 5-aminolaevulinic-acid-dehydratase in blood (ALA-D) have been determined in three pigeon populations (50 birds each), caught at urban sites with different traffic densities. The following mean concentrations were found (Pb-F [mg/kg wet wt.]/ALA-D [U/I]): 10.7/18.8 in the low burdened group, 27.9/10.8 in the moderate burdened group, and 49.5/5.6 in the high burdened group. These values were compared with a controlled group of 50 farm pigeons from two remote pigeonries, sited well away from motorways (Pb-F: 1.0/ALA-D: 35.6). The result was a strong positive correlation of the Pb-F and an inverse correlation of the ALA-D to the number of cars per day at the different sites. These local effects contributed much more to the differences of the Pb-F and ALA-D (in comparison with the rural pigeons) than the over-all elevated lead background level in the city. It has been concluded that the pigeon is an almost ideal animal for monitoring a narrow range of environmental lead burden. The main reason for this is that this species is exceptionally stationary; the usual ranges of the feeding, nesting, and sleeping sites of the pigeon are not greater than several hundred meters.  相似文献   
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