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- A sedução libertina como arte do equívoco em Crébillon e LaclosPublication . Carvalho, Ana Alexandra Mendonça Seabra da Silva Andrade deDe entre toda a literatura que encena a libertinagem, de Ovídio aos nossos dias, Claude Crébillon e Laclos terão sido daqueles que mais argutamente trataram a questão da linguagem equívoca de Eros. No universo fechado e policiado em que circulam as suas personagens, feira de vaidades tão requintada como cruel, o duplo sentido das palavras, não detectado a tempo ou mal interpretado, pode conduzir a uma mise à mort, mesmo quando apenas moral e social, da incauta vítima. Cerimonial estratégico, a sedução é aqui uma relação dual e agonística que visa a derrota/conquista do objecto do desejo, por vezes de forma violenta, empregando o sedutor todas as armas à sua disposição. Discurso essencialmente estratégico, a sedução utiliza um código linguístico e retórico que dissimula as reais intenções do libertino sob a máscara do discurso amoroso.
- Effect of photoperiod on flavonoid pathway activity in sweet potato (Ipomoea batatas (L.) Lam.) leavesPublication . Carvalho, Isabel Saraiva de; Cavaco, Teresa; Carvalho, Lara M.; Duque, PaulaCompared with those of major commercial leafy vegetables, leaves of sweet potato have higher contents of flavonoids and phenolic acids, which provide significant health benefits and may be used as natural colourants. We have analysed the expression of key flavonoid biosynthesis genes using RT-PCR and the accumulation of polyphenolic compounds using high-performance liquid chromatography coupled to a photodiode-array detector, during the development of leaves of sweet potato plants growing under either long day or short day photoperiods. A massive induction of flavonoid pathway gene expression, correlating with a dramatic increase in the content of an anthocyanin, catechins, flavonols, hydroxycinnamic acids and hydroxybenzoic acids, was observed during sweet potato leaf exposure to a long day photoperiod. These results provide further support for the protective role of flavonoids and phenolic acids against enhanced light exposure in plants.
- Projeto mobilidade sustentável. Manual de boas práticas para uma mobilidade sustentávelPublication . Vilão, Regina; Venâncio, Catarina; Silva, Fernando Nunes da; Lajas, Renata; Martins, Rita; Rosa, Maria Manuela PiresO Manual de Boas Práticas para uma Mobilidade Sustentável, doravante designado Manual, surge na sequência dos trabalhos realizados no âmbito do Projecto Mobilidade Sustentável, desenvolvido pela Agência Portuguesa do Ambiente (ex-Instituto do Ambiente) com a colaboração de 15 Centros de Investigação / Universidades de referência no contexto nacional e da articulação interministerial com os elementos do Grupo de Trabalho Ambiente e Transportes (vide Volume I da presente edição). Constituem objectivos deste Manual apresentar os principais tipos de constrangimentos à mobilidade que a vasta experiência acumulada no Projecto Mobilidade Sustentável permitiu reunir e aferir, bem como proceder à divulgação do tipo de soluções que foi possível gizar – e mesmo em alguns casos implementar. De realçar que num contexto de cooperação entre académicos e investigadores, técnicos municipais e autarcas, foi possível testar, em termos de acuidade face aos constrangimentos detectados e à aceitabilidade social e política das soluções propostas, as acções a desenvolver no curto e médio prazos.
- On the possibility of non-invasive multilayer temperature estimation using soft-computing methodsPublication . Teixeira, C. A.; Pereira, W. C. A.; Ruano, Antonio; Ruano, M. GraçaObjective and motivation: This work reports original results on the possibility of non-invasive temperature estimation (NITE) in a multilayered phantom by applying soft-computing methods. The existence of reliable non-invasive temperature estimator models would improve the security and efficacy of thermal therapies. These points would lead to a broader acceptance of this kind of therapies. Several approaches based on medical imaging technologies were proposed, magnetic resonance imaging (MRI) being appointed as the only one to achieve the acceptable temperature resolutions for hyperthermia purposes. However, MRI intrinsic characteristics (e. g., high instrumentation cost) lead us to use backscattered ultrasound (BSU). Among the different BSU features, temporal echo-shifts have received a major attention. These shifts are due to changes of speed-of-sound and expansion of the medium. Novelty aspects: The originality of this work involves two aspects: the estimator model itself is original (based on soft-computing methods) and the application to temperature estimation in a three-layer phantom is also not reported in literature. Materials and methods: In this work a three-layer (non-homogeneous) phantom was developed. The two external layers were composed of (in % of weight): 86.5% degassed water, 11% glycerin and 2.5% agar agar. The intermediate layer was obtained by adding graphite powder in the amount of 2% of the water weight to the above composition. The phantom was developed to have attenuation and speed-of-sound similar to in vivo muscle, according to the literature. BSU signals were collected and cumulative temporal echo-shifts computed. These shifts and the past temperature values were then considered as possible estimators inputs. A soft-computing methodology was applied to look for appropriate multilayered temperature estimators. The methodology involves radial-basis functions neural networks (RBFNN) with structure optimized by the multi-objective genetic algorithm (MOGA). In this work 40 operating conditions were considered, i.e. five 5-mm spaced spatial points and eight therapeutic intensities (I(SATA)): 0.3, 0.5, 0.7, 1.0, 1.3, 1.5, 1.7 and 2:0 W/cm(2). Models were trained and selected to estimate temperature at only four intensities, then during the validation phase, the best-fitted models were analyzed in data collected at the eight intensities. This procedure leads to a more realistic evaluation of the generalisation level of the best-obtained structures. Results and discussion: At the end of the identification phase, 82 (preferable) estimator models were achieved. The majority of them present an average maximum absolute error (MAE) inferior to 0.5 degrees C. The best-fitted estimator presents a MAE of only 0.4 degrees C for both the 40 operating conditions. This means that the gold-standard maximum error (0.5 degrees C) pointed for hyperthermia was fulfilled independently of the intensity and spatial position considered, showing the improved generalisation capacity of the identified estimator models. As the majority of the preferable estimator models, the best one presents 6 inputs and 11 neurons. In addition to the appropriate error performance, the estimator models present also a reduced computational complexity and then the possibility to be applied in real-time. Conclusions: A non-invasive temperature estimation model, based on soft-computing technique, was proposed for a three-layered phantom. The best-achieved estimator models presented an appropriate error performance regardless of the spatial point considered (inside or at the interface of the layers) and of the intensity applied. Other methodologies published so far, estimate temperature only in homogeneous media. The main drawback of the proposed methodology is the necessity of a-priory knowledge of the temperature behavior. Data used for training and optimisation should be representative, i.e., they should cover all possible physical situations of the estimation environment. (C) 2009 Elsevier B.V. All rights reserved.
- On the assessment of time-shift variations from backscattered ultrasound for large temperature changes in biological phantomsPublication . Teixeira, C. A.; Ruano, M. Graça; Pereira, W. C. A.; Garreton, L. G.This work reports the assessment of time-shifts (TS) from backscattered ultrasound (BSU) signals when large temperature variations (up to 15 degrees C) were induced in a gel-based phantom. The results showed that during cooling temperature is linear with TS at a rate of approximately 74 ns/degrees C. However during a complete heating/cooling cycle, the relation is highly non-linear. This can be explained by the fact that during cooling the temperature distribution is more uniform. Another problem to report is that TS is very sensitive to external movements.
- Acclimation of seagrass Zostera noltii to co-occurring hydrodynamic and light stressesPublication . de los Santos, Carmen B.; Brun, Fernando G.; Bouma, Tjeerd J.; Vergara, Juan J.; Pérez-Lloréns, J. LucasSeagrasses may frequently experience a combination of velocity and light stresses, as elevated hydrodynamics often enhances turbidity and the subsequent light reduction. The objective of this study was to investigate the effects that these stressors induce on morphometric and dynamic seagrass features depending on the initial biomass partitioning. For this purpose, a factorial mesocosm experiment was conducted on plants of Zostera noltii subjected to combinations of 2 contrasting light levels (2.5 ± 0.6 and 15.6 ± 2.5 mol photons m–2 d–1) and 3 unidirectional flow velocities (0.35, 0.10 and 0.01 m s–1). No interactive effects between the 2 variables were recorded, except on plant survival and leaf length, and generally, light effects prevailed over hydrodynamic ones. Plants responded to light reduction regardless of the flow velocity treatments, showing low survival rates (which improved at high velocity), high aboveground/belowground biomass ratios (AG/BG) and a poorly developed root-rhizome system compared to plants under saturating light conditions. Plant morphometry only responded to hydrodynamic stress under saturating light: at high current velocity, plants preferentially allocated biomass into BG structures, bearing short leaves and displaying high internode and root appearance rates. Overall, light reduction promoted similar responses in plants with different AG/BG biomass ratios, but dissimilarities were recorded for current velocity. Thus, it can be concluded that, under simultaneous light and hydrodynamic stresses, light effects prevailed over hydrodynamic ones in Z. noltii, while acclimation to hydrodynamics only occurred under saturating light
- Olfactory sensitivity to bile fluid and bile salts in the European eel (Anguilla anguilla), goldfish (Carassius auratus) and Mozambique tilapia (Oreochromis mossambicus) suggests a 'broad range' sensitivity not confined to those produced by conspecifics alonePublication . Huertas, Mar; Hagey, L.; Hofmann, A. F.; Cerda, J.; Canario, Adelino V. M.; Hubbard, PeterTeleosts have high olfactory sensitivity to bile salts. To assess whether this phenomenon is involved in intra-specific chemical communication alone, or is part of a more ‘broad range’ sensitivity to bile salts produced by heterospecifics, we investigated possible differences in the odour of bile between the sexes and among different species – the eel (Anguilla anguilla), goldfish (Carassius auratus) and Mozambique tilapia (Oreochromis mossambicus) – using the electro-olfactogram (EOG). We also identified the main bile constituents by liquid chromatography and mass spectrometry. There were marked differences in olfactory response of the eel to thin-layer chromatography fractions of bile from both sexes, and mature and immature conspecifics. Smaller differences were seen in the potency of fractions of bile from male and female goldfish and tilapia. Eels, goldfish and tilapia demonstrated similar olfactory sensitivity to bile from a range of different species, with no apparent correlation between the olfactory potency of bile and a phylogenetic closeness and/or similarity of diet of the donor to the receiver. The three species were able to detect odorants in thin-layer chromatography fractions of heterospecific bile even in the absence of activity in conspecific bile. Eels, goldfish and tilapia responded to both sulphated C27 bile salts (5-scymnol-sulphate and 5-cyprinol sulphate) and to taurine-conjugated C24 bile salts (taurochenodeoxycholic acid, taurolithocholic acid and taurocholic acid), irrespective of whether these bile salts were present in conspecific bile. Together, these results suggest that teleosts have a broad-range olfactory sensitivity to bile salts, with potential roles in both intra-specific chemical communication and in inter-specific interactions.
- Uma viagem através da LuzPublication . Mesquita, José Carlos VilhenaEste livro gira em torno duma espécie de viagem cósmica impulsionada à velocidade da luz pela força da palavra. A ideia incomensurável do universo físico está patente neste livro através da persistente alusão aos seus elementos constituintes, com particular acinte na luz solar, fonte e gérmen de vida, nos astros que integram o nosso sistema astronómico (estrelas, cometas, planetas, quasares), assim como nas figuras que compõem o nosso universo mítico, como a fénix, a cobra alada, a pedra filosofal, os grifos das trevas e os cavaleiros do apocalipse, os mitos da Esfinge, de Andrómeda e de Prometeu, enfim toda uma panóplia de aparente fantasia científica, que aqui é tratada e transmitida de forma etérea na volatilidade do verso poético.
- The European sea bass Dicentrarchus labrax genome puzzle: comparative BAC-mapping and low coverage shotgun sequencingPublication . Kuhl, H.; Beck, Alfred; Wozniak, Grzegorz; Canario, Adelino V. M.; Volckaert, F.; Reinhardt, RichardAbstract Background Food supply from the ocean is constrained by the shortage of domesticated and selected fish. Development of genomic models of economically important fishes should assist with the removal of this bottleneck. European sea bass Dicentrarchus labrax L. (Moronidae, Perciformes, Teleostei) is one of the most important fishes in European marine aquaculture; growing genomic resources put it on its way to serve as an economic model. Results End sequencing of a sea bass genomic BAC-library enabled the comparative mapping of the sea bass genome using the three-spined stickleback Gasterosteus aculeatus genome as a reference. BAC-end sequences (102,690) were aligned to the stickleback genome. The number of mappable BACs was improved using a two-fold coverage WGS dataset of sea bass resulting in a comparative BAC-map covering 87% of stickleback chromosomes with 588 BAC-contigs. The minimum size of 83 contigs covering 50% of the reference was 1.2 Mbp; the largest BAC-contig comprised 8.86 Mbp. More than 22,000 BAC-clones aligned with both ends to the reference genome. Intra-chromosomal rearrangements between sea bass and stickleback were identified. Size distributions of mapped BACs were used to calculate that the genome of sea bass may be only 1.3 fold larger than the 460 Mbp stickleback genome. Conclusions The BAC map is used for sequencing single BACs or BAC-pools covering defined genomic entities by second generation sequencing technologies. Together with the WGS dataset it initiates a sea bass genome sequencing project. This will allow the quantification of polymorphisms through resequencing, which is important for selecting highly performing domesticated fish.
- Connectivity patterns inferred from the genetic structure of white seabream (Diplodus sargus L.)Publication . Gonzalez-Wanguemert, Mercedes; Canovas, Fernando; Perez-Ruzafa, A.; Marcos, C.; Alexandrino, PauloThemarine environment seems, at first sight, to be a homogeneousmediumlacking barriers to species dispersal. Nevertheless, populations of marine species show varying levels of gene flow and population differentiation, so barriers to gene flow can often be detected. Weaimto elucidate the role of oceanographical factors ingenerating connectivity among populations shaping the phylogeographical patterns in the marine realm, which is not only a topic of considerable interest for understanding the evolution ofmarine biodiversity but also formanagement and conservation of marine life. For this proposal,we investigate the genetic structure and connectivity between continental and insular populations ofwhite seabreamin North East Atlantic (NEA) and Mediterranean Sea (MS) aswell as the influence of historical and contemporary factors in this scenario using mitochondrial (cytochrome b) and nuclear (a set of 9 microsatellite) molecular markers. Azores population appeared genetically differentiated in a single cluster using Structure analysis. This result was corroborated by Principal Component Analysis (PCA) and Monmonier algorithm which suggested a boundary to gene flow, isolating this locality. Azorean population also shows the highest significant values of FST and genetic distances for both molecular markers (microsatellites and mtDNA). We suggest that the breakdown of effective genetic exchange between Azores and the others' samples could be explained simultaneously by hydrographic (deep water) and hydrodynamic (isolating current regimes) factors acting as barriers to the free dispersal of white seabream(adults and larvae) and by historical factors which could be favoured for the survival of Azorean white seabream population at the last glaciation. Mediterranean islands show similar genetic diversity to the neighbouring continental samples and nonsignificant genetic differences. Proximity to continental coasts and the current system could promote an optimal larval dispersion among Mediterranean islands (Mallorca and Castellamare) and coasts with high gene flow.