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Reboredo F.H.,New University of Lisbon | Lidon F.,New University of Lisbon | Pessoa F.,New University of Lisbon | Ramalho J.C.,New University of Lisbon | Ramalho J.C.,Instituto Investigacao Cientifica Tropical
Trends in Biotechnology | Year: 2016

This analysis is focused on the effect of the abrupt decline of oil prices on biofuels, particularly second-generation ethanol. The efforts to decrease the production costs of biofuels, especially cellu- losic ethanol (CE), will be greatly threatened if current oil prices remain low, especially since pro- duction is not slowing. Only huge state subsidies could alleviate this threat, but the challenge is to per- suade citizens that this sacrifice is worthwhile. © 2015 Elsevier Ltd. Source

Ramalho R.S.,University of Bristol | Ramalho R.S.,Lamont Doherty Earth Observatory | Brum Da Silveira A.,University of Lisbon | Fonseca P.E.,University of Lisbon | And 6 more authors.
Geochemistry, Geophysics, Geosystems | Year: 2015

The transition from seamount to oceanic island typically involves surtseyan volcanism. However, the geological record at many islands in the NE Atlantic - all located within the slow-moving Nubian plate - does not exhibit evidence for an emergent surtseyan phase but rather an erosive unconformity between the submarine basement and the overlying subaerial shield sequences. This suggests that the transition between seamount and island may frequently occur by a relative fall of sea level through uplift, eustatic changes, or a combination of both, and may not involve summit volcanism. In this study, we explore the consequences for island evolutionary models using Madeira Island (Portugal) as a case study. We have examined the geologic record at Madeira using a combination of detailed fieldwork, biostratigraphy, and 40Ar/39Ar geochronology in order to document the mode, timing, and duration of edifice emergence above sea level. Our study confirms that Madeira's subaerial shield volcano was built upon the eroded remains of an uplifted seamount, with shallow marine sediments found between the two eruptive sequences and presently located at 320-430 m above sea level. This study reveals that Madeira emerged around 7.0-5.6 Ma essentially through an uplift process and before volcanic activity resumed to form the subaerial shield volcano. Basal intrusions are a likely uplift mechanism, and their emplacement is possibly enhanced by the slow motion of the Nubian plate relative to the source of partial melting. Alternating uplift and subsidence episodes suggest that island edifice growth may be governed by competing dominantly volcanic and dominantly intrusive processes. © 2015. American Geophysical Union. All Rights Reserved. Source

Lidon F.J.C.,New University of Lisbon | Ramalho J.C.,Instituto Investigacao Cientifica Tropical | Pais I.P.,Instituto Nacional Of Investigacao Agraria | Carvalho C.S.,Instituto Nacional Of Investigacao Agraria | And 2 more authors.
Acta Horticulturae | Year: 2012

The use of antagonistic yeasts to control pathogen-induced post harvest diseases, as an alternative to fungicides, appears to be promising. In this context, the yeast-like fungus Aureobasidium pullulans, a wide-spread saprophyte in the phyllosphere, is known to control the Penicillium expansum (blue mold pathogen) in pears. This infection initiates in wounds at harvest and packing, and is closely associated with the synthesis of reactive oxygen species (ROS). As ROS induced oxidative stress may have many detrimental effects, microorganisms that attempt to colonize fresh wounds must cope with this stress triggered at wounding. During longterm storage at low-temperature, oxidative stress may be alleviated by superoxide dismutase and catalase. These enzymes play an important role in the formation and degradation of H2O 2, while ascorbate peroxidase and glutathione reductase are involved in ascorbate regeneration. In this work, the control by A. pullulans on the pathogen P. expansum was investigated, following the hypothesis that an effective antagonist must possess resistance mechanisms to oxidative stress. To this purpose, the interactions between ascorbate content, the kinetics of superoxide dismutase (EC, ascorbate peroxidase (EC, glutathione reductase (EC and catalase (EC were assessed on 'Rocha' pears (Pyrus communis L. 'Rocha') harvested at commercial maturity stage (based on color attributes, L*a*b*) and stored for 5 months at 0.5°C and 95% RH. In wounds infected with P. expansum and inoculated with A. pullulans, the levels of ascorbate decreased whereas the activities of superoxide dismutase, ascorbate peroxidase, glutathione reductase and catalase increased. The antioxidant defence systems are discussed considering the implications on the metabolic retardation of tissue senescence. Source

Nogueira H.,University of Coimbra | Gama A.,University of Coimbra | Gama A.,University of Lisbon | Mourao I.,University of Tras os Montes e Alto Douro | And 4 more authors.
American Journal of Human Biology | Year: 2013

Objectives: This study analyses the associations between children's obesity, sports activity (SA), and perceived environmental characteristics with the children's SES. Methods: A sample of 1,885 Portuguese children, aged 3-10 years, living in Coimbra, Portugal, was observed. Weight and height were measured and obesity was defined by age-and sex-specific, BMI cut-off points. Questionnaires included variables on SA levels, SES and parental neighborhood perceptions were done. A CATPCA was performed and two neighborhood dimensions were achieved. The independent associations of SES with obesity, SA and perceived neighborhood dimensions was analyzed using ordered logistic regressions. Results: Children of low [odds ratio (OR)=1.76; confidence interval (CI)=1.25-1.99] and medium SES (OR=1.57; CI=1.34-2.33) were more likely to be obese than their high-SES peers, less likely to participate in SA (low SES OR=0.177; CI=0.12-0.26; medium SES OR=0.357; CI=0.24-0.53), and their parents were less likely to have positive perceptions of their built environment (low SES OR=0.516; CI=0.38-0.70; medium SES OR=0.565; CI=0.37-0.86). Conclusions: Obesity increases and SA decreases among children with the lowest SES and these living in neighborhoods with higher perceived risk. This finding suggests a model of environmental injustice, whereby differential access to the neighborhood's resources overlaps with familial socioeconomic disadvantage. © 2013 Wiley Periodicals, Inc. Source

Nogueira H.,University of Coimbra | Ferrao M.,University of Coimbra | Gama A.,University of Coimbra | Gama A.,University of Lisbon | And 4 more authors.
Health and Place | Year: 2013

This study investigates the links between parents' perceptions of their social and built residential environment and obesity among Portuguese school boys and girls. A total of 1885 children, 952 girls and 933 boys, aged 3.0-10.0 years, were observed. The children's weight and height were measured, and their parents filled out the "Environmental Module" questionnaire of the International Physical Activity Prevalence Study. Age and sex-specific BMI cut-off points were used to define being overweight/obese. Environmental characteristics were combined into 2 composite neighborhood indices that were used as predictors in logistic regression models. Girls living in neighborhoods perceived as having poorly built environmental conditions had increased odds of being obese (OR=1.47; p<0.005), and girls living in neighborhoods perceived as being unsafe and dangerous had also increased odds of being obese (OR=1.339; p<0.005). These relationships were not evident for boys. Improvements in the neighborhood environment could be a strategy for tackling the growing epidemic of childhood obesity and can simultaneously contribute to reduce health iniquities across population subgroups. © 2012 Elsevier Ltd. Source

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