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Edmilson F. de Oliveira-Filho Kennya G. S. Lopes Deivson S. Cunha Virginia S. Silva Clara N. Barbosa Daniel F. Brandespim José Wilton Pinheiro Junior Giovani R. Bertani Laura H. V. G. Gil 《Food and environmental virology》2017,9(3):256-259
Anti-HEV antibodies were detected in animals from abattoir and in farms from northeast Brazil. Our results suggest that HEV is highly disseminated in the swine population and might present a great risk to animal handlers and for consumption of raw or undercooked meat and meat products in northeast Brazil. 相似文献
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The recycling of municipal solid waste has a remarkable importance in the preservation of the environment and the welfare of the society. However, it is also important that this service can be provided with efficient costs. This paper aims to search for economies of output density and economies of size in the selective collection and recycling activities in Portugal and to identify the size the utilities should have to become more cost efficient. The sample comprises all Portuguese recycling utilities operating in the wholesale segment in the period 2006–2010. The results show that the Portuguese recycling utilities should increase the quantities of municipal solid waste for recycling (especially glass and paper) and also become larger to dimensions corresponding to a supply of 400–550 thousand inhabitants. With the increasing amount of glass collected, utilities are simultaneously struggling to fulfill the targets established by the European legislation and explore the existing economies of output density. The results also show that the management of these services carried out by private companies and the use of incineration (by utilities) seem to reduce the costs of utilities while the regulation of these services and the composting of waste held by utilities tend to increase costs. 相似文献
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This paper examines the merits and the perverse effects of quality of service regulation in the performance of urban waste services when implemented alone and compares the performance of different economic regulatory methods. By means of a productivity analysis, we investigate the influence of a five-year period of regulation on the performance of Portuguese urban waste utilities using an unbalanced panel data for the period 2001-2008. Different non-parametric methods were applied to estimate the productivity change, all leading to similar outcomes. We observed a tendency of productivity decline in the urban waste utilities and concluded that in spite of the unequivocal improvements in the quality of service induced by sunshine regulation, more should be done as far as economic regulation is concerned. We also found that the use of sunshine regulation together with low incentive economic regulatory methods is not positive, leading to overinvestment rather than to value for money. 相似文献
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Margarida Liz Martins Luís M. Cunha Sara S.P. Rodrigues Ada Rocha 《Waste management (New York, N.Y.)》2014,34(8):1362-1368
The aim of this study was to validate the visual estimation method for aggregated plate waste of main dish at Portuguese primary school canteens. For this purpose plate waste at school lunch was measured for 505 individual servings, using weighing individual servings and plate waste and visual estimation method by a 6-point scale, as developed by Comstock et al. (1981). A high variability of initial serving weights was found with serving sizes ranging from 88.9 to 283.3 g and with a coefficient of variation ranging from 5.5% to 24.7%. Mean plate waste was 27.5% according to the weighing method. There was a significant bias in the conversion of the visual waste estimations to actual waste, being overestimated by an average of 8.0 g (ranging from ?12.9 g to 41.4 g). According to Bland and Altman plot, the mean difference between methods was of 8.0 g and the amplitude interval was 102.6 g. The study showed that the visual estimation method is not as accurate as the weighing method in assessing nonselective aggregated plate waste at primary school canteens. Our findings are thus very important on considering plate waste assessment, since the wide variation on initial servings introduces a relevant bias when considering standard portions or a random sample of initial servings. Although, greater convenience, time-saving and the possibility to monitor plate waste of large groups, make the visual estimation method an important method to assess plate waste at school canteens, these results highlighted the need of portions standardization and control of initial servings to allow for its use. 相似文献
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dos Santos Clécia Andrade de Souza Cruz Daiane Requião da Silva Wenes Ramos de Jesus Gleyce Kelly Santos Alessandra Ferreira da Cunha Graziele Costa Wisniewski Alberto Romão Luciane Pimenta Cruz 《Environmental science and pollution research international》2021,28(19):23929-23945
Environmental Science and Pollution Research - A simple, efficient, environmentally friendly, and inexpensive synthesis route was developed to obtain a magnetic nano-hybrid (GH) based on graphene... 相似文献
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Susana Garrido Rui Rosa Radhouan Ben-Hamadou Maria Emilia Cunha Maria Alexandra Chícharo Carl D. van der Lingen 《Marine Biology》2008,154(6):1053-1065
Temporal variation in the fatty acid (FA) composition of stomach contents of Iberian sardines was compared to the relative
contribution to dietary carbon made by different prey types for fish from two areas off Portugal. The effect of the FA content
of the diet on sardine muscle FA composition was also studied, aiming at (1) analysing if FA biomarkers can be used as a complementary
technique for the study of sardine diet and (2) to relate spatial and temporal variations of prey FA content with sardine
condition and reproduction. Significant spatial differences in the FA composition of sardine diet occurred with concentrations
of n-3 polyunsaturated FA, namely eicosapentaenoic acid [EPA, 20:5n-3] and linolenic acid 18:3n-3, being significantly higher
in the diet of sardines from the west coast, whilst the diet of sardines from the south coast was richer in monounsaturated
fatty acids (MUFA), namely the carnivory biomarker oleic acid 18:1n-9. These results are in agreement with the higher contribution
made by diatoms and dinoflagellates to the diet of sardines off the west coast. Spatial variation in sardine dietary FA was
also detected in their muscle composition, specifically for EPA, and the eicosapentaenoic/docosahexaenoic acid and (n-3)/(n-6)
ratios, which were higher in sardines from the west coast. No difference in FA composition was detected between sexes, and
the seasonal variability in sardine total FA concentration was primarily related to the seasonality of spawning. Sardines
accumulate high concentrations of FAs during the resting stage of reproduction when the feeding intensity is similar or lower
to that observed during the spawning season. Additionally, sardines show a high selective retention of MUFA and polyunsaturated
FA (PUFA) throughout the year except at the beginning of the spawning season, when these FAs are largely invested in the formation
of the gonads. Therefore, temporal and regional differences of prey environments are strong enough to be reflected in fish
body composition, namely on the accumulation of essential FAs, which can have a strong impact on reproduction success for
this species. 相似文献
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Pedro Simões Kristof De Witte Rui Cunha Marques 《Waste management (New York, N.Y.)》2010,30(6):1130-1137
This research computes the influence of the operational environment on the efficiency of the Portuguese urban solid waste services. A sample of 29 solid waste utilities encompassing the whole continental country was used for this purpose. Particularly, we apply the non-parametric double bootstrap model to estimate the effect of various explanatory factors on robust data envelopment analysis estimates. In general, we find a significant influence of the environmental context on the solid waste utilities’ performance. The environmental context is characterized by gross domestic product per capita, distance to treatment facilities, population density, regulation, type of management, composting and incineration services. 相似文献