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Mourato S.,Polytechnic Institute of Leiria | Mourato S.,Institute of Mediterranean Agricultural and Environmental science ICAAM | Moreira M.,University of Evora | Moreira M.,Institute of Mediterranean Agricultural and Environmental science ICAAM | Corte-Real J.,Institute of Mediterranean Agricultural and Environmental science ICAAM
Journal of Urban and Environmental Engineering | Year: 2014

Regional climate models provided precipitation and temperature time series for control (1961-1990) and scenario (2071-2100) periods. At southern Portugal, the climate models in the control period systematically present higher temperatures and lower precipitation than the observations. Therefore, the direct input of climate model data into hydrological models might result in more severe scenarios for future water availability. Three bias correction methods (Delta Change, Direct Forcing and Hybrid) are analysed and their performances in water availability impact studies are assessed. The Delta Change method assumes that the observed series variability is maintained in the scenario period and is corrected by the evolution predicted by the climate models. The Direct Forcing method maintains the scenario series variability, which is corrected by the bias found in the control period, and the Hybrid method maintains the control model series variability, which is corrected by the bias found in the control period and by the evolution predicted by the climate models. To assess the climate impacts in the water resources expected for the scenario period, a physically based spatially distributed hydrological model, SHETRAN, is used for runoff projections in a southern Portugal basin. The annual and seasonal runoff shows a runoff decrease in the scenario period, increasing the water shortage that is already experienced. The overall annual reduction varies between -80% and -35%. In general, the results show that the runoff reductions obtained with climate models corrected with the Delta Change method are highest but with a narrow range that varies between -80% and -52%. © 2014 Journal of Urban and Environmental Engineering (JUEE). All rights reserved.

Veiga A.,University of Evora | Dordio A.,University of Evora | Carvalho A.J.P.,University of Evora | Teixeira D.M.,University of Evora | And 2 more authors.
Analytica Chimica Acta | Year: 2010

A multi-walled carbon nanotubes (MWCNTs) film-coated glassy carbon electrode (GCE) was used for the voltammetric determination of carbamazepine (CBZ). The results showed that this simple modified electrode exhibited excellent electrocatalytic activity towards the oxidation of CBZ. The voltammetric response of CBZ at this film-modified electrode increased significantly when compared with that at a bare glassy carbon electrode and the sensor response was reproducible. The proposed method was applied to the quantification of CBZ in wastewater samples, collected in a municipal wastewater treatment plant, and in pharmaceutical formulations. The developed methodology yields results in accord with those obtained by chromatographic techniques commonly used in the quantification of pharmaceutical compounds in real samples. Good recoveries have been obtained and the limits of detection and quantification (40 and 140. nM, respectively) are among the lowest that have been reported to date for this pharmaceutical compound using voltammetric techniques. © 2010 Elsevier B.V.

Calado J.M.G.,University of Evora | Calado J.M.G.,Institute of Mediterranean Agricultural and Environmental science ICAAM | Basch G.,University of Evora | Carvalho M.,University of Evora
Planta Daninha | Year: 2011

The emergence of weed plants depends on environmental conditions, especially temperature and soil moisture. The latter is extremely important in Mediterranean environments which are characterized by irregular amount and distribution of rain throughout the year, which influences the beginning of the growth cycle of the annual species (seed germination). This paper studies the influence of rainfall, in particular accumulated rainfall in autumn, on the emergence of weed plants. The experiment was carried out on Luvisols, and the appearance of flora under field conditions was observed. Through analysis of the results, it can be concluded that a high percentage of weed plants (> 85% related to the highest registered value) was obtained with more than 90 mm of accumulated rainfall from the beginning of September. Thus, in those years in which this amount of rainfall (90 mm) is registered until the end of October, the appearance of potential weed plants can be ensured, under Mediterranean conditions, in a period before sowing the autumn-winter crops.

Lavrador C.,Institute of Mediterranean Agricultural and Environmental science ICAAM | Mascarenhas R.,Institute of National Agricultural and Veterinary Research INIAV | Coelho P.,University of Lisbon | Brites C.,University of Coimbra | And 2 more authors.
Journal of Materials Science: Materials in Medicine | Year: 2016

Abstract: Bone substitutes have been a critical issue as the natural source can seldom provide enough bone to support full healing. No bone substitute complies with all necessary functions and characteristics that an autograft does. Polyurethane sponges have been used as a surgical alternative to cancellous bone grafts for critical bone defect donor sites. Critical bone defects were created on the tibial tuberosity and iliac crest using an ovine model. In group I (control-untreated), no bone regeneration was observed in any animal. In group II (defects left empty but covered with a microporous polymeric membrane), the new bone bridged the top ends in all animals. In groups III and IV, bone defects were implanted with polyurethane scaffolds modified with biologically active compounds, and bone regeneration was more efficient than in group II. In groups III and IV there were higher values of bone regeneration specific parameters used for evaluation (P < 0.05) although the comparison between these groups was not possible. The results obtained in this study suggest that biodegradable polyurethane substitutes modified with biologically active substances may offer an alternative to bone graft, reducing donor site morbidity associated with autogenous cancellous bone harvesting. Graphical Abstract: [Figure not available: see fulltext.] © 2016, Springer Science+Business Media New York.

Calado J.M.G.,University of Evora | Calado J.M.G.,Institute of Mediterranean Agricultural and Environmental science ICAAM | Basch G.,University of Evora | Basch G.,Institute of Mediterranean Agricultural and Environmental science ICAAM | And 4 more authors.
Plant Protection Quarterly | Year: 2013

Emergence of weeds is influenced by disturbance of the top soil layer which, in general, creates favourable environmental conditions for the germination of seeds and consequent plant emergence. This study reports the influence of soil disturbance on the emergence of weeds under different soil moisture levels. The experiments were carried out under controlled environment conditions, using rings containing undisturbed soil cores collected from the top soil layer (0-2.5 cm and 0-5.0 cm depths) of a Luvisol. The treatments comprised two depths and four moisture levels in disturbed and undisturbed soil. The results showed that both moisture level and soil disturbance greatly influence weed seedling emergence. Emerged seedlings in the disturbed soil, which had been subject to a moisture level greater than or equal to two thirds field capacity, was higher in number than in the undisturbed soil. However, soil subject to saturation followed by desiccation produced fewer seedlings when the soil was disturbed.

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