Browsing by Issue Date, starting with "2018-06"
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- Soft-bottom fishes and spatial protection: findings from a temperate marine protected areaPublication . Sousa, Inês; Gonçalves, Jorge Manuel Santos; Claudet, Joachim; Coelho, Rui; Gonçalves, Emanuel J.; Erzini, KarimNumerous studies over the last decades have focused on marine protected areas (MPAs) and their effects on fish communities. However, there is a knowledge gap regarding how species that live associated with soft-substrates (e.g., sand, mud) respond to spatial protection. We analyzed abundance, biomass and total lengths of the soft-bottom fishes in a multiple-use MPA in the north-eastern Atlantic, the Luiz Saldanha Marine Park (Portugal), during and after the implementation of its management plan. Data were collected by experimental fishing in areas with three different levels of protection, during the implementation period and for three years after full implementation of the MPA. Univariate analysis detected significant biomass increases between the two periods. Fish assemblages were mainly structured by depth and substrate, followed by protection level. Community composition analyses revealed significant differences between protection levels and between the two periods. Species exhibited a broad variation in their response to protection, and we hypothesize that factors such as species habitat preferences, body size and late maturity might be underlying determinants. Overall, this study provides some evidence of protection effectiveness in soft-bottom fish communities, supported by the significant increase in biomass in the protected areas and the positive trends of some species.
- Light is more important than nutrient ratios of fertilization for cymodocea nodosa seedling developmentPublication . Alexandre, Ana; Silva, João; Santos, RuiRestoration of seagrass beds through seedlings is an alternative to the transplantation of adult plants that reduces the impact over donor areas and increases the genetic variability of restored meadows. To improve the use of Cymodocea nodosa seedlings, obtained from seeds germinated in vitro, in restoration programs, we investigated the ammonium and phosphate uptake rates of seedlings, and the synergistic effects of light levels (20 and 200 mu mol quanta m(-2) s(-1)) and different nitrogen to phosphorus molar ratios (40 mu M N:10 mu M P, 25 mu M N:25 mu M P, and 10 mu N:40 mu M P) on the photosynthetic activity and growth of seedlings. The nutrient content of seedlings was also compared to the seed nutrient reserves to assess the relative importance of external nutrient uptake for seedling development. Eighty two percent of the seeds germinated after 48 days at a mean rate of 1.5 seeds per day. All seedlings under all treatments survived and grew during the 4 weeks of the experiment. Seedlings of C. nodosa acquired ammonium and phosphate from the incubation media while still attached to the seed, at rates of about twice of adult plants. The relevance of external nutrient uptake was further highlighted by the observation that seedlings' tissues were richer in nitrogen and phosphorus than non-germinated seeds. The uptake of ammonium followed saturation kinetics with a half saturation constant of 32 mu M whereas the uptake of phosphate increased linearly with nutrient concentration within the range tested (5 - 100 mu M). Light was more important than the nutrient ratio of fertilization for the successful development of the young seedlings. The seedlings' photosynthetic and growth rates were about 20% higher in the high light treatment, whereas different nitrogen to phosphorus ratios did not significantly affect growth. The photosynthetic responses of the seedlings to changes in the light level and their capacity to use external nutrient sources showed that seedlings of C. nodosa have the ability to rapidly acclimate to the surrounding light and nutrient environment while still attached to the seeds. C. nodosa seedlings experiencing fertilization under low light levels showed slightly enhanced growth if nourished with a balanced formulation, whereas a slight increase in growth was also observed with unbalanced formulations under a higher light level. Our results highlight the importance of high light availability at the seedling restoration sites.
- Persistence of travel and leisure sector equity indicesPublication . Andraz, Jorge; Guerreiro, Raúl Filipe C.; Rodrigues, Paulo M. M.Volatility persistence of travel and leisure sector equity indices and of some of its components is analyzed, and tests of whether persistence has changed over time are performed. Given the typical leading indicator behavior of financial variables, understanding and characterizing the properties of these indices may help shed light on the behavior of the tourism sector and of its resilience to crises. For the purpose of analysis, our sample is split into three subsamples according to the World tourism cycle: (i) from January 1996 to December 2002; (ii) from January 2003 to August 2007; and (iii) from September 2007 to July 2014. Results suggest the existence of long-memory dynamics driving series volatility, and that shocks to volatility tend to be more persistent during periods of turmoil and affect regions differently.
- The use of artificial neural networks to estimate seismic damage in traditional masonry buildingsPublication . Ferreira, Tiago Miguel; Estêvão, João Manuel Carvalho; Maio, Rui; Vicente, RomeuThe present paper aims to discuss alternative strategies to estimate earthquake damage inflicted to traditional masonry buildings through a comparative analysis of the results obtained resorting to two different approaches: a seismic vulnerability index scoring method and physical damage estimation, widely used in the past in numerous large-scale earthquake risk assessment studies, and an innovative approach based on the use of Artificial Neural Networks. The post-earthquake damage data collected in the aftermath of the magnitude VII earthquake that struck the Azores archipelago (in Portugal) on July 9, 1998, was used to generate real damage data for a set of traditional masonry buildings located in the island of Faial. This data was then compared to the analytical results obtained through the referred approaches for different macroseismic intensities, IEMS-98. Finally, the fitting of the mean damage grade values estimated by the scoring method and calculated through the artificial neural network are compared and critically discussed.
- O monstruoso na literatura e outras artesPublication . Carvalho, João Carlos Firmino Andrade de; Carvalho, Ana Alexandra Mendonça Seabra da Silva Andrade deEntre 20 de outubro de 2017 e 9 de fevereiro de 2018 realizou-se um Ciclo de Conferências, dedicado à temática da representação do monstruoso na literatura e outras artes, iniciativa resultante da parceria entre o Departamento de Artes e Humanidades da Faculdade de Ciências Humanas e Sociais da Universidade do Algarve e a Biblioteca Municipal de Faro “António Ramos Rosa”. O evento, que decorreu nas instalações da Biblioteca Municipal de Faro e da delegação regional do Instituto Português do Desporto e Juventude, teve por objetivo a divulgação da temática teratológica, quer no plano literário quer no de outras artes, suscitando a reflexão analítico-interpretativa em torno de diferentes formas de configuração da monstruosidade em diversos momentos históricos (da Antiguidade à Contemporaneidade), e dirigiu- -se a um público heterogéneo, constituído por círculos de leitores e usuários da Biblioteca, por círculos escolares, universitários e culturais da cidade e da região, bem como por outros interessados na especificidade da temática abordada. Reúnem-se agora, neste livro, as versões escritas dessas nove conferências proferidas por especialistas das áreas da literatura e outras artes, disponibilizando, deste modo, ao Leitor, o resultado escrito da reflexão, análise e interpretação propostas por cada um dos autores. Queremos deixar aqui o nosso agradecimento aos autores que, prontamente, aderiram a esta iniciativa e disponibilizaram os seus textos, bem como ao Centro de Literaturas e Culturas Lusófonas e Europeias da Faculdade de Letras da Universidade de Lisboa (CLEPUL) que tornou possível a sua publicação.
- Migrations and habitat use of the smooth hammerhead shark (Sphyrna zygaena) in the Atlantic OceanPublication . Santos, Catarina C.; Coelho, RuiThe smooth hammerhead shark, Sphyrna zygaena, is a cosmopolitan semipelagic shark captured as bycatch in pelagic oceanic fisheries, especially pelagic longlines targeting swordfish and/or tunas. From 2012 to 2016, eight smooth hammerheads were tagged with Pop-up Satellite Archival Tags in the inter-tropical region of the Northeast Atlantic Ocean, with successful transmissions received from seven tags (total of 319 tracking days). Results confirmed the smooth hammerhead is a highly mobile species, as the longest migration ever documented for this species (> 6600 km) was recorded. An absence of a diel vertical movement behavior was noted, with the sharks spending most of their time at surface waters (0-50 m) above 23 degrees C. The operating depth of the pelagic long-line gear was measured with Minilog Temperature and Depth Recorders, and the overlap with the species vertical distribution was calculated. The overlap is taking place mainly during the night and is higher for juveniles (similar to 40% of overlap time). The novel information presented can now be used to contribute to the provision of sustainable management tools and serve as input for Ecological Risk Assessments for smooth hammerheads caught in Atlantic pelagic longline fisheries.
- The use of chloroplast genome sequences to solve phylogenetic incongruences in Polystachya Hook (Orchidaceae Juss)Publication . de Abreu, Narjara Lopes; Valka Alves, Ruy Jose; Sodre Cardoso, Sergio Ricardo; Bertrand, Yann J. K.; Sousa, Filipe; Hall, Climbie Ferreira; Pfeil, Bernard E.; Antonelli, AlexandreBackground: Current evidence suggests that for more robust estimates of species tree and divergence times, several unlinked genes are required. However, most phylogenetic trees for non-model organisms are based on single sequences or just a few regions, using traditional sequencing methods. Techniques for massive parallel sequencing or next generation sequencing (NGS) are an alternative to traditional methods that allow access to hundreds of DNA regions. Here we use this approach to resolve the phylogenetic incongruence found in Polystachya Hook. (Orchidaceae), a genus that stands out due to several interesting aspects, including cytological (polyploid and diploid species), evolutionary (reticulate evolution) and biogeographical (species widely distributed in the tropics and high endemism in Brazil). The genus has a notoriously complicated taxonomy, with several sections that are widely used but probably not monophyletic. Methods: We generated the complete plastid genome of 40 individuals from one clade within the genus. The method consisted in construction of genomic libraries, hybridization to RNA probes designed from available sequences of a related species, and subsequent sequencing of the product. We also tested how well a smaller sample of the plastid genome would perform in phylogenetic inference in two ways: by duplicating a fast region and analyzing multiple copies of this dataset, and by sampling without replacement from all non-coding regions in our alignment. We further examined the phylogenetic implications of non-coding sequences that appear to have undergone hairpin inversions (reverse complemented sequences associated with small loops). Results: We retrieved 131,214 bp, including coding and non-coding regions of the plastid genome. The phylogeny was able to fully resolve the relationships among all species in the targeted clade with high support values. The first divergent species are represented by African accessions and the most recent ones are among Neotropical species. Discussion: Our results indicate that using the entire plastid genome is a better option than screening highly variable markers, especially when the expected tree is likely to contain many short branches. The phylogeny inferred is consistent with the proposed origin of the genus, showing a probable origin in Africa, with later dispersal into the Neotropics, as evidenced by a clade containing all Neotropical individuals. The multiple positions of Polystachya concreta (Jacq.) Garay & Sweet in the phylogeny are explained by allotetraploidy. Polystachya estrellensis Rchb.f. can be considered a genetically distinct species from P. concreta and P. foliosa (Lindl.) Rchb.f., but the delimitation of P. concreta remains uncertain. Our study shows that NGS provides a powerful tool for inferring relationships at low taxonomic levels, even in taxonomically challenging groups with short branches and intricate morphology.
- Incorporation of capric acid in pumpkin seed oil by sn-1,3 regioselective lipase-catalyzed acidolysisPublication . Sousa, Vanessa; Campos, Vitor; Nunes, Patricia; Pires-Cabral, PaulaStructured lipids (SLs) are novel triacylglycerols obtained by changing the native fatty acid (FA) profiles or by the incorporation of a new desired FA in the acylglycerol backbone. These modified fats present important medical and functional properties for food applications. This work aimed to synthetize a MLM-type SL, which consists of triacylglycerols containing a medium-chain FA (M) at sn-1,3 positions and a long-chain FA (L) at sn-2 position, by acidolysis of pumpkin seed oil with capric acid, catalyzed by a commercial lipase preparation from Thermomyces lanuginosa (Lipozyme TL IM). Reactions were performed at 45 degrees C, in solvent-free media, at 1: 2 molar ratio (pumpkin seed oil: capric acid) and a fixed amount of immobilized lipase of 5%, 10%, 15% or 20%. Incorporations of C10: 0 increased with time up to 31 h (29.9 +/- 0.7 mol-%) when 5% lipase load was used. Significant differences were only observed between the results obtained with 5 and 20% of biocatalyst load. The subsequent experiment was carried out with 5% lipase load, at 45 degrees C, 1: 2 molar ratio and in the presence of n-hexane. The results showed slightly higher incorporation yields in the presence of solvent, namely at 48 h-reaction (34.7 +/- 1.0 mol-%). However, since the structured lipids are to be used in food products, together with environmental and economic concerns, solvent-free systems are preferred. In this study, the synthesis of a MLM-type SL from pumpkin seed oil for food uses was well succeeded.
- A minimum cross entropy approach to disaggregate agricultural data at the field levelPublication . Xavier, Antonio; Fragoso, Rui; Costa Freitas, M. B.; Rosario, Maria do Socorro; Valente, FlorentinoAgricultural policies have impacts on land use, the economy, and the environment and their analysis requires disaggregated data at the local level with geographical references. Thus, this study proposes a model for disaggregating agricultural data, which develops a supervised classification of satellite images by using a survey and empirical knowledge. To ensure the consistency with multiple sources of information, a minimum cross-entropy process was used. The proposed model was applied using two supervised classification algorithms and a more informative set of biophysical information. The results were validated and analyzed by considering various sources of information, showing that an entropy approach combined with supervised classifications may provide a reliable data disaggregation.
- Earthquake resilient schools in Algarve (Portugal) and Huelva (Spain)Publication . Estêvão, João Manuel Carvalho; Ferreira, Mónica A.; Morales-Esteban, Antonio; Martínez-Álvarez, Francisco; Fazendeiro-Sá, Luis; Requena-García-Cruz, Victoria; Segovia-Verjel, M. Luisa; Oliveira, Carlos S.Earthquake hazard is present in the south-western Iberian Peninsula (southern Portugal and south-western Spain), going beyond borders. Earthquakes cause important impacts in children. Consequently, schools play a vital role in increasing the seismic resilience. This can be regarded in two manners: (i) by decreasing the structural vulnerability launching retrofitting programs and (ii) by increasing the awareness and capacity of the student population in dealing with the phenomenon before, during and after the event. A project named Projetos de Escolas Resilientes aos SISmos no Território do Algarve e de Huelva, in Portuguese (PERSISTAH) aims the development of diagnostic tools, evaluation, management and rehabilitation of primary schools in both regions. Preparing support material for teachers is also intended. All these aims are developed in compliance with the National Civil Protection Policies of both Portugal and Spain. Both countries have signed the Hyogo and Sendai Agreements for disaster risk reduction. PERSISTAH proposes accomplishing the following tasks: creating a hierarchy system for the vulnerability of primary schools (school-score); forming mixed teams with experts from both countries to evaluate the school buildings; developing recommendations for rehabilitation with practical implementation in two pilot schools; and developing educational material and a practical guide to support the education and communication of risk to the school population. The general methodology to generate the school-score is presented in this paper.