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11.
Andréia Dalla Vecchia Mariana Kluge Joseane V. dos Santos da Silva Juliana Comerlato Manoela T. Rodrigues Juliane D. Fleck Roger B. da Luz Thais F. Teixeira Paulo M. Roehe Roberta Capalonga Ana Beatriz Oliveira Fernando R. Spilki 《Food and environmental virology》2013,5(1):41-45
Torque teno virus (TTV) was surveyed in tap water collected in schools from three municipalities located in the south of Brazil. TTV genomes were found in 11.7 % (4/34) of the samples. TTV DNA was detected in 10.5 % (2/19) of the samples collected at the city of Caxias do Sul and in 25 % (2/8) of the samples from Pelotas. Those cities have a low rate of sewage treatment. All samples from Santa Cruz do Sul, which has nearly 92 % of its sewage treated, were negative. These results suggest that the amount of sewage treated may have an effect on the detection rates of TTV DNA in drinking water in a given urban area, showing a mild negative correlation (r = ?0.76), when comparing the percentage of sewage treatment to the detection of TTV genomes. The detection rate of TTV was also compared with Escherichia coli, showing a strong correlation (r = 0.97), indicating that TTV may be a suitable marker of fecal contamination. 相似文献
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Samira Veiga Ravaiano Ríudo de Paiva Ferreira Lucio Antonio de Oliveira Campos Gustavo Ferreira Martins 《Die Naturwissenschaften》2014,101(8):603-611
The sensilla of insects are integumental units that play a role as sensory structures and are crucial for the perception of stimuli and for communication. In this study, we compared the antennal sensilla of females (workers and queens), males (haploid (n) and diploid (2n)), and queen-like males (QLMs, resulting from 2n males after juvenile hormone (JH) treatment) in the stingless bee Melipona quadrifasciata. Images of the dorsal antenna surfaces were acquired using a scanning electron microscope. As reported for other hymenopterans, this species exhibits a heterogeneous sensillar distribution along the antennae. Thirteen different types of sensilla were found in the antennae of M. quadrifasciata: trichodea (subtypes I to VI), chaetica (subtypes I and II), placodea, basiconica, ampullacea, coeloconica, and coelocapitula. Sensilla trichodea I were the most abundant, followed by sensilla placodea, which might function in olfactory perception. Sensilla basiconica, sensilla chaetica I, sensilla coeloconica, and sensilla ampullacea were found exclusively in females. In terms of the composition and size of the sensilla, the antennae of QLMs most closely resemble those of the 2n male, although QLMs exhibit a queen phenotype. This study represents the first comparative analysis of the antennal sensilla of M. quadrifasciata. The differences found in the type and amount of sensilla between the castes and sexes are discussed based on the presumed sensillary functions. 相似文献
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The behaviour of ashes and heavy metals during the co-combustion of sewage sludges in a fluidised bed 总被引:1,自引:0,他引:1
Helena Lopes M Abelha P Lapa N Oliveira JS Cabrita I Gulyurtlu I 《Waste management (New York, N.Y.)》2003,23(9):859-870
Co-combustion tests of dry sewage sludges with coal were performed in a pilot bubbling FBC aiming at the characterization of ashes and determining the behaviour of heavy metals in the process. The tests showed compliance with the regulatory levels as far as heavy metal emissions were concerned. The bottom ashes, which accounted for about 70% of the total ash production, were obtained in a granular form, with diameters ranging from 0.5 to 4 mm. The heavy metals were distributed in ashes obtained from different locations of the installation and their concentrations were found to vary depending on the location of capture. The increase in heavy metals content in bottom ashes was not found to lead to higher leachability and ecotoxicity compared to sewage sludges, suggesting that there could be opportunities for their further use. Mercury suffered vaporisation inside the reactor, thus leaving bottom ashes free of contamination by it. However, there was observed a strong retention of mercury in cyclone ashes due to the presence of unburned carbon which probably acted as an adsorbent. The effluent mercury was also found to be mostly associated with the particulate fraction, being less than 20% emitted in gaseous forms. The results suggested that the combustion of the sewage sludge could successfully be carried out and the amount of unburned carbon leaving the combustor but captured in cyclone was large enough to ensure substantial retention of mercury at low temperatures, hence could contribute to an improvement of the mercury release which still remains an issue of great concern to resolve during combustion of waste materials. 相似文献
16.
Most harvestmen are nocturnal, nonacoustical, and nonvisual arthropods. They have a pair of exocrine glands on the cephalothorax that produce defensive volatile secretions. We investigated in the field the possible alarm effect of these secretions in the gregarious harvestman Goniosoma aff. proximum. A cotton swab soaked with the species' own exudate (treatment), or with water (control), was held 1-2 cm from the center of harvestmen aggregations. The results showed that the gland secretion elicits an alarm response in Goniosoma: whereas 73.3% of the aggregations dispersed after being stimulated with the gland exudate, only 3.3% responded to the water control. Respondent groups are larger than nonrespondent groups, and the time of reaction to the secretion was inversely related to group size. This is the first demonstration of a chemically-mediated alarm effect in harvestmen. The alarm response in gregarious harvestmen has possibly evolved as a by-product of a primarily defensive reaction in the context of predator avoidance. The discovery of this novel function of scent-gland secretion is meaningful in view of the widespread occurrence of gregarious habit among species of the order Opiliones. 相似文献
17.
Nelzair A. Vianna Daniel Gonçalves Flavia Brandão Roberta P. de Barros Gilberto M. Amado Filho Rodrigo O. Meire João Paulo M. Torres Olaf Malm Argemiro D’Oliveira Júnior Leonardo R. Andrade 《Environmental science and pollution research international》2011,18(3):416-427
Purpose
The aims of this paper were to quantify the heavy metals (HM) in the air of different sites in Rio de Janeiro (RJ) and Salvador (SA) using Tillandsia usneoides (Bromeliaceae) as a biomonitor, and to study the morphology and elemental composition of the air particulate matter (PM) retained on the Tillandsia surface. 相似文献18.
Otávio José de Oliveira Camila Roberta Muniz Serra Pinheiro 《Journal of Cleaner Production》2009,17(9):883-885
Among the difficulties found in the implementation of ISO 14001 systems, resistance to change can always be found. It is mainly a consequence of the hurry to change, loss of focus, concentration of decision making at the level of top management, arbitrary imposition of objectives and results, faulty communication, and the absence of motivational and financial incentive for change.Therefore, the main objective of this paper is to present best practices with respect to the management of organizational change due to the implementation of ISO 14001 norms in two industrial companies in the Midwest region of the State of São Paulo – Brazil. 相似文献
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Otávio José de Oliveira José Roberto Serra Manoel Henrique Salgado 《Journal of Cleaner Production》2010,18(18):1797-1806
As a result of increasing global awareness about the importance of the environment, depletion of natural resources and legal pressures for companies to manage their processes in a sustainable manner, ISO 14001 systems have been gaining increasingly more importance in the organizational scenario. These elements are even more critical in emerging nations due to less awareness and fewer demands by governments and the population in relation to environmental issues. Therefore, the main objective of this study is to verify the benefits and difficulties of Environmental Management Systems based on ISO 14001 at industries in the state of São Paulo – Brazil (an emerging country) by conducting a survey to subsidize the proposal for actions in the public, academic and private sectors to promote the use of this standard of reference and strengthen its results in Brazil. A questionnaire was sent to 194 companies from the National Institute of Metrology, Standardization and Industrial Quality database. 69 answered, representing a return rate of 35.36%. The main benefits identified are related to the development of preventive environmental actions, reduction in the consumption of power, water, gas and fuel oil, and a positive influence on other internal management processes. The main difficulties are related to cost increases from ISO 14001 management systems and the constant changes in environmental legislation in Brazil. Some actions are proposed at the end of the analyses to intensify the use and improve the results of this standard, such as changes in government legislation and its collective development and implementation in industries. 相似文献