Browsing by Issue Date, starting with "2014-08"
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- Seismic vulnerability assessment of existing masonry buildings: case study of the old city centre of Faro, PortugalPublication . Vicente, Romeu; Ferreira, Tiago; Maio, Rui; Varum, Humberto; Costa, Alexandre A.; Costa, Aníbal; Oliveira, Carlos S.; Estêvão, João Manuel CarvalhoThe seismic vulnerability and risk assessment of old city centre areas is truly essential in urban rehabilitation programs and should not be focused exclusively over recognized historical and patrimonial valuable buildings but also in relation to current old masonry buildings that are highly valued in urban context. In addition, due to their geographical, demographic or historical features some old city centres are particularly interesting and critical, in respect to seismic risk mitigation. An excellent example of this reality is the old city of Faro, Capital of the Algarve, Portugal, which is one of the most popular summer touristic destination in Europe in a prone seismic region. This fact explains the high seasonal flux of population, which together with the moderate to high seismic hazard of the Algarve region and a vulnerable building stock increases both the seismic and tsunami risk in this area. From the exposed, this paper approaches the seismic vulnerability assessment of old building stock through the application of a simplified vulnerability method to the old city centre of Faro. Such method is based on a vulnerability index, which can be used to evaluate physical damage and to create human and economic loss scenarios in a broad sense (Vicente et al., 2011). 191 buildings were evaluated in accordance with the referred methodology and the results obtained were subsequently integrated into a Geographical Information System (GIS) tool, which allows the spatial analysis of results (Ferreira et al., 2013).This tool constitutes a very valuable instrument for city councils and regional authorities, whom can decide in a faster and more accurate way the best risk mitigation strategies to follow at the urban scale.
- Dynein-dependent transport of spindle assembly checkpoint proteins off kinetochores toward spindle polesPublication . Silva, PMA; Patrícia M.A. Silva; Reis, Rita M.; Bolanos-Garcia, Victor M.; Florindo, Claudia; Tavares, Alvaro; Bousbaa, HassanA predominant mechanism of spindle assembly checkpoint (SAC) silencing is dynein-mediated transport of certain kinetochore proteins along microtubules. There are still conflicting data as to which SAC proteins are dynein cargoes. Using two ATP reduction assays, we found that the core SAC proteins Mad1, Mad2, Bub1, BubR1, and Bub3 redistributed from attached kinetochores to spindle poles, in a dynein-dependent manner. This redistribution still occurred in metaphase-arrested cells, at a time when the SAC should be satisfied and silenced. Unexpectedly, we found that a pool of Hec1 and Mis12 also relocalizes to spindle poles, suggesting KMN components as additional dynein cargoes. The potential significance of these results for SAC silencing is discussed. (C) 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
- Applicability of the “Frame of Reference” approach for environmental monitoring of offshore renewable energy projectsPublication . Garel, Erwan; Rey, Cibran Camba; Ferreira, Óscar; van Koningsveld, MarkThis paper assesses the applicability of the Frame of Reference (FoR) approach for the environmental monitoring of large-scale offshore Marine Renewable Energy (MRE) projects. The focus is on projects harvesting energy from winds, waves and currents. Environmental concerns induced by MRE projects are reported based on a classification scheme identifying stressors, receptors, effects and impacts. Although the potential effects of stressors on most receptors are identified, there are large knowledge gaps regarding the corresponding (positive and negative) impacts. In that context, the development of offshore MRE requires the implementation of fit-for-purpose monitoring activities aimed at environmental protection and knowledge development. Taking European legislation as an example, it is suggested to adopt standardized monitoring protocols for the enhanced usage and utility of environmental indicators. Towards this objective, the use of the FoR approach is advocated since it provides guidance for the definition and use of coherent set of environmental state indicators. After a description of this framework, various examples of applications are provided considering a virtual MRE project located in European waters. Finally, some conclusions and recommendations are provided for the successful implementation of the FoR approach and for future studies.
- Characteristics of magnetic solar-like cycles in a 3D MHD simulation of solar convectionPublication . Passos, D.; Charbonneau, P.We analyse the statistical properties of the stable magnetic cycle unfolding in an extended 3D magnetohydroclynamic simulation of solar convection produced with the EULAG-MHD code. The millennium,simulation spans over 1650 years, in the course of which forty polarity reversals take place on a regular similar to 40yr cadence, remaining well-synchronized across solar hemispheres. In order to characterize this cycle and facilitate its comparison with measures typically used to represent solar activity, we build two proxies for the magnetic field in the simulation mimicking the solar toroidal field and the polar radial field. Several quantities that characterize the cycle are measured (period, amplitudes, etc.) and correlations between them are computed, These are then compared with their observational analogs. From the typical Gnevyshesv-Ohl pattern, to hints of Gleissberg modulation the simulated cycles share many of the characteristics of their observational analogs even though the simulation lacks poloidal field regeneration through active region decay, a mechanism nowadays often considered an essential component of the solar dynamo. Some significant discrepancies are, also identified, most notably the in-phase variation of the simulated poloidal and toroidal large-scale magnetic components, and the low degree of hemispheric coupling at the level of hemispheric cycle amplitudes. Possible causes underlying these discrepancies are discussed.
- Effects of active pharmaceutical ingredients mixtures in mussel Mytilus galloprovincialisPublication . Gonzalez-Rey, Maria; Mattos, J.J.; Piazza, C.E.; Bainy, A.C.D.; Bebianno, Maria JoãoActive pharmaceutical ingredients (APIs) are emergent environmental contaminants widely detected in surface waters as result of incomplete waste water treatment plant (WWTP) removal processes and improper disposal. The assessment of potential effects of APIs on non-target organisms is still scarce since besides presenting multiple chemical structures, properties and modes of action, these compounds occur as complex mixtures. This study comprises a 15-day exposure of mussels Mytilus galloprovincialis to mixtures (at environmentally relevant nominal concentrations) of non-steroidal inflammatory drugs ibuprofen (IBU) and diclofenac (DCF) (250 ng L(-1) each) and selective serotonin reuptake inhibitor (SSRI) fluoxetine (FLX) (75 ng L(-1)) (MIX 1) along with the addition of classical pro-oxidant copper (Cu) (5 μg L(-1)) (MIX 2). The goals included the assessment of oxidative stress, neurotoxic and endocrine effects on this sentinel species applying both a multibiomarker and gene expression (here and later gene expression is taken as synonym to gene transcription, although it is acknowledged that it is also affected by, e.g. translation, and mRNA and protein stability) analysis approaches. The results revealed a swifter antioxidant response in digestive glands than in gills induced by MIX 1, nevertheless the presence of Cu in MIX 2 promoted a higher lipid peroxidation (LPO) induction. Neither mixture altered acetylcholinesterase (AChE) activity, while both triggered the formation of vitellogenin-like proteins in females confirming the xenoestrogenic effect of mixtures. All these results varied with respect to those obtained in previous single exposure essays. Moreover, RT-PCR analysis revealed a catalase (CAT) and CYP4Y1 gene expression down- and upregulation, respectively, with no significant changes in mRNA levels of genes encoding superoxide dismutase (SOD) and glutathione-S-transferase (GST). Finally, this study highlights variable tissue and time-specific biomarker responses and gene expression alterations, which along with several interactions between each mixture component on each biomarker confirm the susceptibility of mussels to API mixtures.
- Disentangling the Influence of Mutation and Migration in Clonal Seagrasses Using the Genetic Diversity Spectrum for MicrosatellitesPublication . ARNAUD-HAOND, Sophie; Moalic, Yann; Hernandez-Garcia, Emilio; Eguíluz, Víctor M.; Alberto, Filipe; Serrao, Ester A.; Duarte, Carlos M.The recurrent lack of isolation by distance reported at regional scale in seagrass species was recently suggested to stem from stochastic events of large-scale dispersal. We explored the usefulness of phylogenetic information contained in microsatellite loci to test this hypothesis by using the Genetic Diversity Spectrum (GDS) on databases containing, respectively, 7 and 9 microsatellites genotypes for 1541 sampling units of Posidonia oceanica and 1647 of Cymodocea nodosa. The simultaneous increase of microsatellite and geographic distances that emerges reveals a coherent pattern of isolation by distance in contrast to the chaotic pattern previously described using allele frequencies, in particular, for the long-lived P. oceanica. These results suggest that the lack of isolation by distance, rather than the resulting from rare events of large-scale dispersal, reflects at least for some species a stronger influence of mutation over migration at the scale of the distribution range. The global distribution of genetic polymorphism may, therefore, result predominantly from ancient events of step-by-step (re) colonization followed by local recruitment and clonal growth, rather than contemporary gene flow. The analysis of GDS appears useful to unravel the evolutionary forces influencing the dynamics and evolution at distinct temporal and spatial scales by accounting for phylogenetic information borne by microsatellites, under an appropriate mutation model. This finding adds nuance to the generalization of the influence of large-scale dispersal on the dynamics of seagrasses.
- Personalizing medicine for metastatic colorectal cancer: Current developmentsPublication . Marques, Andrea Marin; Turner, Alice; De Mello, Ramon AndradeMetastatic colorectal cancer (mCRC) is still one of the tumor types with the highest incidence and mortality. In 2012, colorectal cancer was the second most prevalence cancer among males (9%) and the third among females (8%). In this disease, early diagnosis is important to improve treatment outcomes. However, at the time of diagnosis, about one quarter of patients already have metastases, and overall survival of these patients at 5-years survival is very low. Because of these poor statistics, the development of new drugs against specific targets, including the pathway of angiogenesis, has witnessed a remarkable increase. So, targets therapies through epidermal growth factor and its receptor and also KRAS pathways modulation acquired a main role whether in association with standard chemotherapy and radiotherapy. With the current knowledge in the field of molecular biology, including genetic mutations and polymorphisms, we know better why patients respond so differently to the same treatments. So, in the future we can develop increasingly personalized treatments to the patient and not the disease. This review aims to summarize some molecular pathways and their relation to tumor growth, as well as novel targeted developing drugs and recently approved for mCRC. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.
- Effects of estrogens and estrogenic disrupting compounds on fish mineralized tissuesPublication . Pinto, Patricia IS; Estevao, Maria D.; Power, Deborah M.Estrogens play well-recognized roles in reproduction across vertebrates, but also intervene in a wide range of other physiological processes, including mineral homeostasis. Classical actions are triggered when estrogens bind and activate intracellular estrogen receptors (ERs), regulating the transcription of responsive genes, but rapid non-genomic actions initiated by binding to plasma membrane receptors were recently described. A wide range of structurally diverse compounds from natural and anthropogenic sources have been shown to interact with and disrupt the normal functions of the estrogen system, and fish are particularly vulnerable to endocrine disruption, as these compounds are frequently discharged or run-off into waterways. The effect of estrogen disruptors in fish has mainly been assessed in relation to reproductive endpoints, and relatively little attention has been given to other disruptive actions. This review will overview the actions of estrogens in fish, including ER isoforms, their expression, structure and mechanisms of action. The estrogen functions will be considered in relation to mineral homeostasis and actions on mineralized tissues. The impact of estrogenic endocrine disrupting compounds on fish mineralized tissues will be reviewed, and the potential adverse outcomes of exposure to such compounds will be discussed. Current lacunae in knowledge are highlighted along with future research priorities.
- A green strategy for shark attack mitigation off Recife, BrazilPublication . Hazin, Fábio H. V.; André S. AfonsoShark attacks on humans have prompted the implementation of shark control programs aiming at reducing local populations of potentially aggressive species using mostly gillnets. However, shark meshing produces ecological disturbances by inflicting severe mortality not only to sharks but also to several harmless, frequently endangered taxa, including cetaceans, sirenians and chelonids. A different methodological approach to mitigate shark peril off Recife combines bottom longlining and drumlines with comparably better results. This region has been experiencing an abnormally high shark attack rate since 1992, but the protective fishing strategy was developed in 2004 only. Unlike traditional shark control programs, the Shark Monitoring Program of Recife (SMPR) aims at removing dangerous sharks not from their populations but from the hazardous area instead, which is achieved by capturing, transporting and releasing sharks offshore. During 8 years, the SMPR caught fish and turtles only and showed high selectivity for sharks compared with shark meshing. Target species comprised carcharhinids and sphyrnids and accounted for 7% of total catch. The fishing mortality of abundant taxa was generally low except for Carcharhinus acronotus and Gymnothorax spp., and protected species had similar to 100% survival. The shark attack rate diminished about 97% while fishing operations were being conducted (W = 1108.5, P < 0.001), whereas no-fishing periods and the period prior to the implementation of the SMPR had similar shark attack rates. Overall, the SMPR seems to be less detrimental than shark meshing strategies while clearly contributing for enhancing bather safety; thus, it may provide an effective, ecologically balanced tool for assisting in shark attack mitigation.
- Phytophthora acerina sp nov., a new species causing bleeding cankers and dieback of Acer pseudoplatanus trees in planted forests in northern ItalyPublication . Ginetti, Beatrice; Moricca, S.; Squires, J. N.; Cooke, D. E. L.; Ragazzi, A.; Jung, T.A severe dieback of Acer pseudoplatanus trees was noticed in planted forest stands in northern Italy in 2010. Affected trees showed collar rot and aerial bleeding cankers along the stems, leading to crown dieback and eventually death. An unknown Phytophthora species was consistently isolated from necrotic bark and xylem tissue and from rhizosphere soil. Based on its unique combination of morphological and physiological characters and phylogenetic analysis, this new taxon is here described as Phytophthora acerina sp. nov. Phylogenetic analysis of ITS, cox1 and beta-tubulin gene regions demonstrated that P. acerina is unique and forms a separate cluster within the 'P. citricola complex', closely related to P. plurivora. Phytophthora acerina is homothallic with smooth-walled oogonia, thick-walled, mostly aplerotic oospores with a high abortion rate, paragynous antheridia, and persistent, morphologically variable semipapillate sporangia. Four to 5-week-old cultures produced globose to subglobose, appressoria-like and coralloid hyphal swellings and characteristic stromata-like hyphal aggregations. Optimum and maximum temperatures for growth are 25 degrees C and 32 degrees C, respectively. Genetic uniformity of all 15 studied isolates and the apparent absence of this species in the extensive surveys of nurseries, forests and seminatural ecosystems conducted in the previous two decades across Europe indicate a recent clonal introduction to northern Italy. Under-bark inoculation tests demonstrated high aggressiveness of P. acerina to A. pseudoplatanus indicating that this pathogen might be a serious risk to maple plantations and forests in Europe.