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Lucas-Borja M.E.,University of Castilla - La Mancha | Fonseca T.F.,University of Tras os Montes e Alto Douro | Lousada J.L.,Center for the Research and Technology of Agro Environmental and Biological science | Silva-Santos P.,Modelling and Environment | And 2 more authors.
Ecological Research | Year: 2012

Information on plant seed dispersal, natural loss dynamics of seeds and germination are critical for understanding natural regeneration mechanisms. The aim of this study was to assess the effect of different forest stand densities on seedfall, seed predation, and seedling germination of two populations of the endangered Spanish black Pine forests located at lower (Central population) and higher elevation near the limit of the species' range (peripheral population) in the Cuenca Mountains of Central Spain. The seed predation and germination experiment also included a nested site preparation treatment. Seed fall varied significantly between 2006 and 2005 or 2007 in both populations. During the only mast year of 2006, higher seedfall was observed at lower elevation and in higher density stands. Predation rates were influenced by the seed crop since predators consumed more than 75 % of seeds in years with lower production and less than 15 % in a mast year. Seed germination is influenced by forest habitat, stand density and soil scalping. For common habitat types, and in a high seed production year, better seed germination rates were observed in medium and dense stands (25-30 and 35-40 m 2 ha -1, respectively, in terms of basal area). No statistical difference in seed germination rate was found for Spanish black pine forest at its ecological distribution limit between lower and higher densities (15-20 and 35-40 m 2 ha -1, in terms of basal area). In both sites, closed stands with soil scalping exhibited higher germination rates. © 2012 The Ecological Society of Japan. Source

Rainha N.,University of The Azores | Lima E.,University of The Azores | Baptista J.,University of The Azores | Fernandes-Ferreira M.,Center for the Research and Technology of Agro Environmental and Biological science | And 2 more authors.
Natural Product Research | Year: 2013

This study reports the first quantification study of pseudohypericin (PsHyp) and hypericin (Hyp) in Hypericum undulatum Schousb. ex Willd in vitro cultures developed by a Portuguese company. Both compounds were quantified by high-performance liquid chromatography and their levels were compared with those in commercial samples of Hypericum perforatum. PsHyp was found to be the major naphthodianthrone of H. undulatum, with an average ratio of 3.73:1 compared to Hyp. Significant statistical differences were found between the content of Hyp and PsHyp in H. undulatum regenerated shoots compared to in vivo samples. The mean concentration of total Hyps varied from 178.41 to 358.93 g g-1 dry extract in H. undulatum regenerated shoots, which is on average two to three times less than naphthodianthrone levels found in H. undulatum in vivo and H. perforatum commercial samples. However, none of the analysed samples presented the levels of Hyps required by the European and United States Pharmacopoeias. © 2013 Taylor & Francis. Source

Monteiro-Cardoso V.F.,University of Tras os Montes e Alto Douro | Oliveira M.M.,University of Tras os Montes e Alto Douro | Melo T.,University of Aveiro | Domingues M.R.M.,University of Aveiro | And 4 more authors.
Journal of Alzheimer's Disease | Year: 2014

Brain mitochondria are fundamental to maintaining healthy functional brains, and their dysfunction is involved in age-related neurodegenerative disorders such as Alzheimer's disease (AD). In this study, we conducted a research on how both non-synaptic and synaptic mitochondrial functions are compromised at an early stage of AD-like pathologies and their correlation with putative changes on membranes lipid profile, using 3 month-old nontransgenic and 3xTg-AD mice, a murine model of experimental AD. Bioenergetic dysfunction in 3xTg-AD brains is evidenced by a decrease of brain ATP levels resulting, essentially, from synaptic mitochondria functionality disruption as indicated by declined respiratory control ratio associated with a 50% decreased complex I activity. Lipidomics studies revealed that synaptic bioenergetic deficit of 3xTg-AD brains is accompanied by alterations in the phospholipid composition of synaptic mitochondrial membranes, detected either in phospholipid class distribution or in the phospholipids molecular profile. Globally, diacyl- and lyso-phosphatidylcholine lipids increase while ethanolamine plasmalogens and cardiolipins content drops in relation to nontransgenic background. However, the main lipidomic mark of 3xTg-AD brains is that cardiolipin cluster-organized profile is lost in synaptic mitochondria due to a decline of the most representative molecular species. In contrast to synaptic mitochondria, results support the idea that non-synaptic mitochondria function is preserved at the age of 3 months. Although the genetically construed 3xTg-AD mouse model does not represent the most prevalent form of AD in humans, the present study provides insights into the earliest biochemical events in AD brain, connecting specific lipidomic changes with synaptic bioenergetic deficit that may contribute to the progressive synapses loss and the neurodegenerative process that characterizes AD. © 2015 - IOS Press and the authors. Source

Monteiro-Cardoso V.F.,University of Tras os Montes e Alto Douro | Castro M.,University of Tras os Montes e Alto Douro | Oliveira M.M.,University of Tras os Montes e Alto Douro | Moreira P.I.,University of Coimbra | And 2 more authors.
Current Alzheimer Research | Year: 2015

The emergence of Alzheimer's disease as a systemic pathology shifted the research paradigm toward a better understanding of the molecular basis of the disease considering the pathophysiological changes in both brain and peripheral tissues. In the present study, we evaluated the impact of disease progression on physiological relevant features of skeletal muscle obtained from 3, 6 and 12 month-old 3xTg-AD mice, a model of Alzheimer's disease, and respective age-matched nonTg mice. Our results showed that skeletal muscle functionality is already affected in 3-month-old 3xTg-AD mice as evidenced by deficient acetylcholinesterase and catalase activities as well as by alterations in fatty acid composition of mitochondrial membranes. Additionally, an age-dependent accumulation of amyloid-p1-40 peptide occurred in skeletal muscle of 3xTg-AD mice, an effect that preceded bioenergetics mitochondrial dysfunction, which was only detected at 12 months of age, characterized by decreased respiratory control ratio and ADP/O index and by an impairment of complex I activity. HPLC-MS/MS analyses revealed significant changes in phospholipid composition of skeletal muscle tissues from 3xTg-AD mice with 12 months of age when compared with age-matched nonTg mice. Increased levels of lyso-phosphatidylcholine associated with a decrease of phosphatidylcholine molecular species containing arachidonic acid were detected in 3xTg-AD mice, indicating an enhancement of phospholipase A2 activity and skeletal muscle inflammation. Additionally, a decrease of phosphatidylethanolamine plasmalogens content and an increase in phosphatidylinositol levels was observed in 3xTg-AD mice when compared with age-matched nonTg mice. Altogether, these observations suggest that the skeletal muscle of 3xTg-AD mice are more prone to oxidative and inflammatory events. © 2015 Bentham Science Publishers. Source

Sanches Fernandes L.F.,Royal University | Sanches Fernandes L.F.,Center for the Research and Technology of Agro Environmental and Biological science | Terencio D.P.S.,Royal University | Pacheco F.A.L.,UTAD | Pacheco F.A.L.,Chemistry Research Center
Science of the Total Environment | Year: 2015

A rainwater harvesting system (RHS) was designed for a waste treatment facility located near the town of Mirandela (northern Portugal), to be used in the washing of vehicles and other equipment, the cleaning of outside concrete or asphalt floors, and the watering of green areas. Water tank volumes representing 100% efficiency (Vr) were calculated by the Ripple method with different results depending on two consumption scenarios adopted for irrigation. The RHS design was based on a precipitation record spanning a rather long period (3 decades). The calculated storage capacities fulfilled the water demand even when prolonged droughts occurred during that timeframe. However, because the drought events have been rather scarce the Vr values were considered oversized and replaced by optimal volumes. Notwithstanding the new volumes were solely half of the original Vr values, the projected RHS efficiency remained very high (around 90%) while the probability of system failure (efficiency < 100%) stayed very low (in the order of 5%). In both scenarios, the economic savings related to the optimization of Vr were noteworthy, while the investment's return periods decreased substantially from the original to the optimized solutions. A high efficiency with a low storage capacity is typical of low demanding applications of rainwater harvesting, where water availability (Vw) largely exceeds water demand (Cw), that is to say where demand fractions (Cw/. Vw) are very low. Based on the results of a literature review covering an ample geographic distribution and describing a very large number of demand fraction scenarios, a Cw/. Vw=. 0.8 was defined as the threshold to generally distinguish the low from the high demanding RHS applications. © 2015 Elsevier B.V. Source

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