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Glycera dibranchiata Ehlers and G. americana Leidy are two closely related and similar species of polychaetes. Electrophoretic studies of 11 enzyme systems encoded by 15 loci reveal that both species are polymorphic at about 50% of their enzyme loci, but that G. dibranchiata is the more variable as judged by heterozygosity per individual, genetic diversity, and effective number of alleles per locus. Both species show marked heterozygote deficiencies at nearly all polymorphic loci, possibly as the result of life-history features. Genetic similarity between the Glycera species suggests divergence at a level between species and sibling species compared to the Drosophila willistoni complex. 相似文献
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Gusti Mykola Forsell Nicklas Havlik Petr Khabarov Nikolay Kraxner Florian Obersteiner Michael 《Mitigation and Adaptation Strategies for Global Change》2019,24(6):1123-1141
Mitigation and Adaptation Strategies for Global Change - Climate change mitigation policies for the land use, land use change, and forestry (LULUCF) sector are commonly assessed based on marginal... 相似文献
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Pharmaceuticals in STP effluents and their solar photodegradation in aquatic environment 总被引:34,自引:0,他引:34
The presence of pharmaceutical compounds in surface waters is an emerging environmental issue. Sewage treatment plants (STPs) are recognized as being the main point discharge sources of these substances to the environment. A monitoring campaign of STP effluents was carried out in four European countries (Italy, France, Greece and Sweden). More than 20 individual pharmaceuticals belonging to different therapeutic classes were found. For six selected pharmaceuticals (carbamazepine, diclofenac, clofibric acid, ofloxacin, sulfamethoxazole and propranolol) present in the STP effluents, the persistence towards abiotic photodegradation was evaluated submitting them to solar experiments at 40° N latitude during spring and summer. Based on experimentally measured quantum yields for the direct photolysis in bi-distilled water, half-life times (t1/2) at varying seasons and latitude were predicted for each substance. In salt- and organic-free (bi-distilled) water carbamazepine and clofibric acid are characterized by calculated half-life times of the order of 100 days at the highest latitudes (50° N) in winter, whereas under the same conditions sulphamethoxazole, diclofenac, ofloxacin and propranolol undergo fast degradation with t1/2 respectively of 2.4, 5.0, 10.6 and 16.8 days. For almost all studied compounds, except propranolol the presence of nitrate ions in aqueous solutions results in a reduction of t1/2. When present, humic acids act as inner filters towards carbamazepine and diclofenac, and as photosensitizers towards sulphamethoxazole, clofibric acid, oflaxocin and propranolol. 相似文献
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