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41.
To explore the concentrations and dynamics of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in Finnish semi-domesticated reindeer (Rangifer tarandus tarandus L.) the reindeer milk and tissue samples were collected from the sub-arctic northern Finland. Reindeer milk's PCB sum (1.20 ng g(-1) wet weight) and PCDD/F sum (0.70 pg g(-1) ww) in autumn were higher than in summer (PCBs 0.50 ng g(-1) ww and PCDD/Fs 0.20 pg g(-1) ww). The mean fat content in autumn milk (26%) was significantly higher than in summer (10%). Concentrations in reindeer milk were generally far below 50% of that in adult reindeer body burden. However, the bioaccumulation factors were multiple in milk/reindeer calf ratio and that aroused the question of other important exposure routes than lactation. The muscle and liver of reindeer calves had higher PCDD/F and PCB concentrations than adult animals that possibly indicate the significance of transfer of these compounds from dam to calf through lactation and placenta. However, PBDE concentrations were higher in adult reindeer, especially in liver. In addition, reindeer liver seems to have a special feature to collect highly toxic PCDD/Fs, although the PCB sum concentrations (range from 0.33 to 1.69 ng g(-1) wet weight) were clearly higher than the sums of PCDD/Fs (range from 3.78 to 39.2 pg g(-1) ww). Stillborn reindeer calves represented individuals who had got their PCDD/F, PCB and PBDE load only via the placenta. Concentrations in muscle and brown adipose tissue samples did not indicate dependency on fat content. Obviously effective placental transfer of PCBs and PBDEs from reindeer dam to foetus was seen in this study.  相似文献   
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The aim of this research is to determine the lethal concentration (LC(50-96 h)) of fungicide tebuconazole for common carp (Cyprinus carpio) and to investigate the occurrence of oxidative stress and metabolic changes after acute exposure to different concentrations of tebuconazole. For this purpose, several parameters were assessed as whole-body levels of thiobarbituric acid-reactive substance (TBARS), protein carbonyl, catalase, superoxide dismutase, glutathione S-transferase, nonprotein thiols, ascorbic acid, glycogen, glucose, lactate, protein, amino acids and ammonia in tebuconazole-exposed fish. The calculated LC(50-96 h) was 2.37 mg L(-1). Fish exhibited significant increase in TBARS levels in all concentrations used while the enzymatic and nonenzymatic antioxidants were decreased. Among the metabolic parameters, glycogen and glucose increased at 1.19 mg L(-1) and protein levels decreased at 1.78 and 2.37 mg L(-1). In conclusion, the fish health was adversely affected by exposure to tebuconazole, and those changes can compromise animal survival in the natural environment. The results indicate that the some of the parameters measured like a possible biomarkers of exposure to tebuconazole for this species of fish.  相似文献   
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Service quality in a construction technology laboratory can result in an improvement in construction companies’ competitiveness. This research aims to evaluate the service quality provided by a construction technology laboratory, specifically in the segment of performing testing through the rupturing of concrete samples. For this research, a survey was conducted using a structured questionnaire that was created based on a literature review regarding the surveying of laboratory customers at a university in the south of Brazil. Our research was both exploratory and quantitative, and the data were analyzed by applying multivariate data analysis. The conclusions of this study show that the dimensions of quality services are: communication, reliability, responsiveness, credibility, and tangibility. These five dimensions together provide a high explained variance standard of 79.75%. Having a suitable number of attendants available to serve customers and presenting agility in the construction laboratory is one of the managerial research contributions. Moreover, through information availability, this research generates greater traceability that can be used both by customers and by institutional management. Constantly and thoroughly monitoring the customer service cycle is another relevant factor that can improve the quality of the services provided.  相似文献   
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Secondary sexual characters have most likely evolved through sexual selection because such traits indicate the genetic or phenotypic quality of the bearer. While genetic variation in such fitness-related traits should be depleted by directional selection, there are many cases in which variation is higher than expected. One hypothesis explaining this variation is that different phenotypes within a population are adapted to different environmental conditions. We tested this hypothesis by comparing the offspring quality of male pied flycatchers, Ficedula hypoleuca, with different degrees of melanin-based dorsal plumage coloration under different environmental conditions. To create different environmental growth conditions and to be able to separate offspring genotype effects from paternal effects on offspring body mass, we used a partial cross-foster design where the brood size was reduced or enlarged by one chick. We also examined the interactive effects of temperature and male phenotype because previous correlative studies suggest such temperature-dependent effects in this species. We show that, while manipulated brood size did not interact with male phenotype to affect offspring quality, temperature during the nestling period influenced the offspring quality of dark and brown foster (but not genetic) fathers. When the temperature was relatively low during the nestling period, foster offspring of black males were lighter than those raised by brown males; the opposite was true if temperature was relatively high. These results add a new aspect to our understanding of how variation in the degree of melanin-based coloration is maintained in wild populations and how phenotypic variation may be maintained in general.  相似文献   
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Surrogate species are used in standard toxicity tests for the environmental risk assessment of chemicals. Test results are then extrapolated to the situation in the field, which is often associated with a large degree of uncertainty. Since a vulnerable species in the field is not only characterised by its intrinsic sensitivity to a stressor but also by its potential for exposure and its population resilience, the identification of focal species based on these three components of vulnerability is needed for a more ecologically relevant risk assessment. This study listed European fish species that are susceptible to pesticide exposure in the field and thus achieved the first step towards identifying focal species for the risk assessment of pesticides for fish in Europe. A step-wise filtering approach was applied to list freshwater fish species that are native to Europe and widespread in the European Union, which inhabit streams, ditches or ponds in agricultural landscapes and therefore, are at an elevated risk of being exposed to pesticides. Out of the 579 fish species occurring in European freshwater, 27 species met the filtering criteria. The resulting list was verified based on monitoring studies that were conducted in agricultural landscapes over the past 20 years. Focal fish species that can be used for a more ecologically relevant environmental risk assessment of pesticides in Europe can be identified from the produced list of species by further assessing their ecological (life history and dispersal characteristics) and intrinsic sensitivities.  相似文献   
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