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This case study examines the ability of the cytochrome P4501A (CYP1A) biomarker to distinguish the pollution status of two small streams, Kr?henbach and K?rsch, receiving different levels of urban and agricultural impact, with low to moderate contamination by arylhydrocarbon receptor (AhR)-binding PAHs and PCBs. Brown trout, Salmo trutta, exposed in enclosure restrictions, showed significant between-stream differences of hepatic CYP1A levels. EROD activities were the better discriminator than CYP1A protein levels. The CYP1A response was consistent and repeatable over the 5-year observation period from 1995 to 1999. In contrast to brown trout, hepatic CYP1A of stone loach, Barbatula barbatula, did not clearly distinguish the streams. The findings of this long-term study lend support to the use of CYP1A as a biomarker of degraded environmental conditions, provided that sufficiently long observation periods are used to average out confounding factors, that sufficiently sensitive detection methods are used, and that a responsive monitoring species is chosen.  相似文献   
23.
The main issues of the studies described were the validation of a test design for the assessment of the bioaccumulation potential of environmental pollutants and the applicability ofEisenia fetida as a model-organism and artificial soil (OECD) as a standard test substrate. The test organisms used wereE. fetida of our own breeding stock andAllolobophora caliginosa, Allolobophora chlorotica, Allolobophora longa and Lumbricus rubellus sampled from a field site. Test soils used were the artificial soil (OECD) and a BBA field soil. Soils were each contaminated with 10 mg HCB and Pyrene per soil dry-weight. Within the test period of 4 weeks, samples were taken weekly for residue analysis in the worms and soils. Bioaccumulation factors (AF) calculated forE. fetida and the free-living species were in the range of 10–17 (HCB) and 0.9–1.7 (Pyrene) depending on the soil used. By re-calculation of the concentrations in soil to concentrations in soil water, the resulting bioconcentration factors are compared with published BCF values determined from QSAR’s of other worm species and fresh water fish. It could be concluded that the existing earthworm tests (OECD 1984, ISO 1998) represent an appropriate design for testing the bioconcentration potential of chemicals in soil.  相似文献   
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Whereas some bird species are heavily affected by blood parasites in the wild, others reportedly are not. Seabirds, in particular, are often free from blood parasites, even in the presence of potential vectors. By means of polymerase chain reaction, we amplified a DNA fragment from the cytochrome b gene to detect parasites of the genera Plasmodium, Leucocytozoon, and Haemoproteus in 14 seabird species, ranging from Antarctica to the tropical Indian Ocean. We did not detect parasites in 11 of these species, including one Antarctic, four subantarctic, two temperate, and four tropical species. On the other hand, two subantarctic species, thin-billed prions Pachyptila belcheri and dolphin gulls Larus scoresbii, were found infected. One of 28 thin-billed prions had a Plasmodium infection whose DNA sequence was identical to lineage P22 of Plasmodium relictum, and one of 20 dolphin gulls was infected with a Haemoproteus lineage which appears phylogenetically clustered with parasites species isolated from passeriform birds such as Haemoproteus lanii, Haemoproteus magnus, Haemoproteus fringillae, Haemoproteus sylvae, Haemoproteus payevskyi, and Haemoproteus belopolskyi. In addition, we found a high parasite prevalence in a single tropical species, the Christmas Island frigatebird Fregata andrewsi, where 56% of sampled adults were infected with Haemoproteus. The latter formed a monophyletic group that includes a Haemoproteus line from Eastern Asian black-tailed gulls Larus crassirostris. Our results are in agreement with those showing that (a) seabirds are poor in hemosporidians and (b) latitude could be a determining factor to predict the presence of hemosporidians in birds. However, further studies should explore the relative importance of extrinsic and intrinsic factors on parasite prevalence, in particular using phylogenetically controlled comparative analyses, systematic sampling and screening of vectors, and within-species comparisons.  相似文献   
25.
Although studies on the evolution and function of female ornaments have become more numerous in the last years, the majority of these studies were carried out in cases where female ornaments were a smaller and duller version of the ornaments found in males. There are substantially fewer studies on species with female-specific ornaments. However, no study so far investigated the potential of female-specific colouration as a quality signal in birds with conventional sex roles. We studied female-specific ornamentation in a strongly sexually dichromatic species, the upland goose Chloephaga picta leucoptera, in two consecutive years. Male upland geese have white head and breast feathers and black legs, whereas females have reddish-brown head and breast feathers and conspicuous yellow-orange legs. We found that female-specific colouration in upland geese can reliably indicate different aspects of female phenotypic quality. Females with more orange coloured legs and more red-like head colours had higher clutch and egg volumes than females with a paler leg and head colouration, and a more reddish plumage colouration was related to a higher body condition. These relationships provide the theoretic possibility for males to assess female phenotypic quality on the basis of colouration. Furthermore, the females with a more orange-like tarsus colouration had higher plasma carotenoid levels. Both tarsus colouration and carotenoid concentrations of individual females were highly correlated across years, indicating that tarsus colour is a stable signal. Despite this correlation, small individual differences in plasma carotenoid concentrations between the two study years were related to differences in tarsus colouration. We thus show for the first time in a wild bird and under natural conditions that carotenoid-based integument colouration remains consistent between individuals in consecutive years and is also a dynamic trait reflecting individual changes in carotenoid levels. In this species, where pairs form life-long bonds, the honesty of the carotenoid-based integument colouration suggests that it may be a sexually selected female ornament that has evolved through male mate choice.  相似文献   
26.
Objective: Norway introduced a “Vision Zero” strategy in 2001, using multiple approaches, aiming toward a future in which no one will be killed or seriously injured in road traffic crashes (RTCs). Official statistics show that the number of fatally injured road users has declined substantially from 341 deaths in 2000 to 117 in 2015. In-depth crash investigations of all fatal RTCs started in Norway in 2005. The aim of this study was to investigate whether fatal crash characteristics, vehicle safety features, and prevalence of drugs and/or alcohol among fatally injured drivers and riders has changed during 2005–2015, accompanying the reduction in road fatalities.

Methods: Data on all car/van drivers and motorcycle/moped riders fatally injured in RTCs during 2005–2015 were extracted from Norwegian road traffic crash registries and combined with forensic toxicology data.

Results: The proportion of cars and motorcycles with antilock braking systems and cars with electronic stability control, increased significantly during the study period. The prevalence of nonuse of seat belts/helmets and speeding declined among both fatally injured drivers and riders. In addition, the prevalence of alcohol declined, though no significant change in the total prevalence of other substances was noted.

Conclusion: The observed changes toward more safety installations in cars and motorcycles and lower prevalence of driver-related risk factors like alcohol use, speeding, and nonuse of seat belts/helmets among fatally injured drivers/riders may have contributed to the decrease in road traffic deaths.  相似文献   

27.
Ecotoxicity of nanosized TiO2. Review of in vivo data   总被引:1,自引:0,他引:1  
This report presents an exhaustive literature review of data on the effect of nanoparticulate TiO2 on algae, higher plants, aquatic and terrestrial invertebrates and freshwater fish. The aim, to identify the biologically important characteristics of the nanoparticles that have most biological significance, was unsuccessful, no discernable correlation between primary particle size and toxic effect being apparent. Secondary particle size and particle surface area may be relevant to biological potential of nanoparticles, but insufficient confirmatory data exist. The nanotoxicity data from thirteen studies fail to reveal the characteristics actually responsible for their biological reactivity because reported nanotoxicity studies rarely carry information on the physicochemical characteristics of the nanoparticles tested. A number of practical measures are suggested which should support the generation of reliable QSAR models and so overcome this data inadequacy.  相似文献   
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29.
Climate change is increasingly affecting organisms and ecosystems. The amount of research and the number of articles in this field is overwhelming. However, single studies necessarily consider limited aspects. Hence, there is an increasing need for structuring the research approaches and findings in climate change research in order to direct future action in an efficient way towards research gaps and areas of uncertainty. Here, we review the current state of knowledge accumulated over the last 10 years (2003–2012) about impacts of climate change on species and ecosystems. Almost 1,200 articles of the scientific literature listed in the ISI Web of Science are analysed. We explore the geographical distribution of knowledge gain, the studied taxonomic groups, ecosystems and environmental parameters as well as the applied methods. Several knowledge gaps arise. Most of the first authors of the analysed articles are residents of North America, Australia or Europe. A similar pattern is found for the study areas. Vascular plants and therewith forests are the most studied taxonomic group and ecosystem. The use of models to estimate potential impacts of climate change is well established in climate change impact research and is continuously developing. However, there is a lack of empirical data derived from experimental climate change simulations. In a rapidly evolving research landscape, this review aims at providing an overview of the current patterns of knowledge distribution and research demands arising from knowledge gaps and biases. Our results should help to identify future research needs and priorities.  相似文献   
30.
Organohalogen contaminants were investigated in Baltic herring caught from three catchment areas in the Baltic Sea, off the coasts of Finland. Pools of both small and large herring were analysed for polychlorinated biphenyls (PCB), dibenzo-p-dioxins, dibenzofurans, naphthalenes, camphenes (toxaphene), polybrominated diphenyl ethers and the pesticide DDT and its metabolites. PCB concentrations per fresh weight in small herring were at the same level in all catchment areas, i.e. the Bothnian Bay, the Bothnian Sea and the Gulf of Finland, revealing no hot spots and reflecting most likely long term emissions and atmospheric deposition. Differences in the levels and/or congener profiles of other contaminants between catchment areas may be explained by point sources. Similar concentrations in small and large herring in the Gulf of Finland were possibly due to their common nutrition. In the other areas, differences between small and large herring most likely reflected their different food sources.  相似文献   
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