596 research outputs found

    Sensibilizar para a entrega de medicamentos usados na farmácia: Qual a importância para o ambiente e fauna selvagem?

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    Actualmente, é cada vez mais importante tratar devidamente os resíduos perigosos para diminuir o seu impacto nos ecossistemas. Neste grupo destacam-se os produtos farmacêuticos que não são considerados resíduos perigosos pelos cidadãos comuns, sendo por isso geralmente depositados no lixo comum. Este facto constui um problema ambiental grave já que vários trabalhos de investigação indicam que a contaminação por fármacos têm efeitos nocivos na fauna e nos ecossistemas

    Behaviour of shot peening combined with WC-Co HVOF coating under complex fretting wear and fretting fatigue loading conditions

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    This study investigated the fretting and fretting fatigue performance of tungsten carbide–cobalt (WC–Co) HVOF spray coating systems. Fretting wear and fretting fatigue tests of specimens with shot peening and WC–Co coatings on 30NiCrMo substrates were conducted. The WC-Co coating presents very good wear resistance and decreases by more than 9 times the energy wear coefficient (α) under fretting conditions. The tested coating reduces crack nucleation under both fretting and fretting fatigue studied situations. Finally the crack arrest conditions are evaluated by the combined fretting and fretting fatigue investigation. It is shown and explained how and why this combined surface treatment (shot peening and WC–Co) presents a very good compromise against wear and cracking fretting damage

    Flight-call as species-specific signal in South American parrots and the effect of species relatedness in call similarity

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    Vocal communication is fundamental to regulate the social interactions in most gregarious species especially after dispersal movements for foraging or predator escape. A species common acoustic signal may be beneficial to group members and is especially critical in species that disperse large distances like parrots. In this study, we investigated whether parrots flight-calls carry species-specific characteristics and tested its variability within and across species. We also assessed the hypothesis of relationship between similarity in species flight-calls and phylogeny. We studied the flight-calls of 10 parrot species all occurring in Cerrado habitat in central Brazil. Our results show that, spectrum wise, there is not a discrete spectral partition between species flight-calls. Flight-calls are conservative within most of the species. Both spectral and temporal dimensions contribute to the difference between species. The species specificity of the calls was confirmed by cross correlation approach. Nevertheless, we found a difference in the call variability with some species exhibiting stereotyped calls (e.g. Amazona aestiva) while others exhibited variable calls (Brotogeris chiriri), suggesting that the function of the flight-call may differ between species, from conveying species signatures to more specific information like group or individual signature. As expected, closely related species have more similar calls. These results show that parrots flight-calls have species-specific characteristics. In some species, these calls can potentially be used in the maintenance of the group or could code other type of information, suggesting that flight-calls may play different roles depending of the species life history.FCT - Fundação para a Ciência e Tecnologiainfo:eu-repo/semantics/publishedVersio

    Extensive beef cattle production in Portugal

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    Portugal, located in the Mediterranean region, one of the "Hot Spot" of the planet, has a huge variability in terms of topography, soils, climate, agriculture, traditions, resulting in a high diversity of animal genetic resources, represented by 15 native cattle breeds, most of them threatened. A significant percentage of extensive beef cattle production in Portugal is based on the use of animals, differing from north to south region, with good maternal aptitude, hardiness, a low growth performance and exceptional adaptation to the environment where they live, and especially to the local feed, naturally produced. In the north of the country and the Azores, dairy breeds predominate, while in the south beef breeds are most prevalent. Portugal is not self-sufficient in beef production, however it is possible to appreciate an market for beef produced by indigenous breeds from extensive and organic production systems. Beef from indigenous breeds is considered to be a high quality product, mainly because of the superior taste and structure of the meat resulting from the production system: slow growth rate and type of vegetation consumed. This product differentiation has allowed the enlargement of small niche markets and has led to an increase in the value of meat with a Protected Designation of Origin (PDO) or with organic beef. Since portuguese agriculture cannot compete on quantity or production cost with other competitors, differentiation and quality seem to be the alternatives that may stimulate rural activities in Less Favoured Areas (LFAs) and create a regional added value able to contribute to sustainable development. Extensive animal production systems can be an important component of environmental and landscape protection, as well as contribute to the decrease of the human, physical desertification of our rural areas and animal genetic resources

    Indicadores econômicos da produção orgânica de minitomate em casas de vegetação

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    Financial profitability is a factor as important as quantifying production using new technologies. This study was installed to evaluate short and long term financial viability of organic production of cherry tomatoes. Plants were grown in a greenhouse under diverse technological degrees for partial control of micrometeorological elements. The experiment was carried out at the experimental field FEAGRI/UNICAMP in three greenhouses with automated mechanical ventilation systems, evaporative cooling and thermo reflective screen. We cultivated Carolina cultivar in a spacing of 0.5x0.9 m, each plant conducted with two stems, under organic production and fertilization management. The average of production data of treatments {three greenhouses (A= climate-controlled, B= mobile screen and C= fixed screen), two cultivation systems (pots and soil beds) and five biofertilizer doses (0, 50, 100, 150, and 200%)} were evaluated using joint analysis. Thus, the economic indicators {cost benefit ratio (B/C), net present value (NPV), internal rate of return (IRR) and Payback (PV)} were evaluated through revenues and production costs. The best alternative to net monthly cycle profitability (500 m2) was approximately 1 and 1.5 minimum wage with and without particular labor, respectively, associated with the greenhouse of medium technological level, using soil bed cultivation system. The economic viability of the project in long-term interest rates above 3% (a.a) was consistent, but the payback period even with a rate of 1% a.a was high (6.54 years) in financing conditions.362246252A rentabilidade financeira é um fator tão importante quanto quantificar a produção utilizando novas tecnologias. Assim, objetivou-se analisar em curto e longo prazo a rentabilidade financeira da produção orgânica de minitomates em casas de vegetação com diferentes graus tecnológicos de controle parcial dos elementos micrometeorológicos. O experimento foi desenvolvido no campo experimental da FEAGRI/UNICAMP (SP) em três casas de vegetação com sistemas automatizados de ventilação mecânica, resfriamento evaporativo e tela termorrefletora, sendo estas cultivadas com a cultivar Carolina em espaçamento 0,5x0,9 m em duas hastes, e manejo da produção e adubação orgânica. As médias dos dados de produção dos tratamentos {três casas de vegetação (A= climatizada, B= tela móvel e C= tela fixa), duas formas de cultivo (vasos e canteiros) e cinco doses de biofertilizante (0, 50, 100, 150, e 200%)} foram avaliadas em análise conjunta. Assim, avaliou-se através das receitas e custos de produção os indicadores econômicos {relação benefício custo (B/C), valor presente líquido (VPL), Taxa interna de retorno (TIR) e Payback (PV)}. De acordo com os resultados, a melhor alternativa de rentabilidade líquida mensal ciclo (500 m2) foi de aproximadamente 1 e 1,5 salários mínimo para a condição com e sem mão de obra particular, respectivamente, associado à casa de vegetação de médio grau tecnológico, utilizando a forma de cultivo em canteiros. A viabilidade econômica do projeto em longo prazo a taxas de juros acima de 3% (a.a) mostrou-se consistente, porém o período de payback mesmo à taxa de juros 1% a.a foi elevada (6,54 anos) em condições de financiamento

    Toxicity of synthetic cathinones in human kidney (HK-2) cells

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    From invasion percolation to flow in rock fracture networks

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    The main purpose of this work is to simulate two-phase flow in the form of immiscible displacement through anisotropic, three-dimensional (3D) discrete fracture networks (DFN). The considered DFNs are artificially generated, based on a general distribution function or are conditioned on measured data from deep geological investigations. We introduce several modifications to the invasion percolation (MIP) to incorporate fracture inclinations, intersection lines, as well as the hydraulic path length inside the fractures. Additionally a trapping algorithm is implemented that forbids any advance of the invading fluid into a region, where the defending fluid is completely encircled by the invader and has no escape route. We study invasion, saturation, and flow through artificial fracture networks, with varying anisotropy and size and finally compare our findings to well studied, conditioned fracture networks.Comment: 18 pages, 10 figure
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