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- Iron deprivation in synechocystis: inference of pathways, non-coding RNAs, and regulatory elements from comprehensive expression profilingPublication . Hernandez-Prieto, Miguel A.; Schoen, Verena; Georg, Jens; Barreira, Luísa; J. C. or Varela J. or Varela J.C.S., Varela; Hess, Wolfgang R.; Futschik, Matthias E.Iron is an essential cofactor in many metabolic reactions. Mechanisms controlling iron homeostasis need to respond rapidly to changes in extracellular conditions, but they must also keep the concentration of intracellular iron under strict control to avoid the generation of damaging reactive oxygen species. Due to its role as a redox carrier in photosynthesis, the iron quota in cyanobacteria is about 10 times higher than in model enterobacteria. The molecular details of how such a high quota is regulated are obscure. Here we present experiments that shed light on the iron regulatory system in cyanobacteria. We measured time-resolved changes in gene expression after iron depletion in the cyanobacterium Synechocystis sp. PCC 6803 using a comprehensive microarray platform, monitoring both protein-coding and non-coding transcripts. In total, less than a fifth of all protein-coding genes were differentially expressed during the first 72 hr. Many of these proteins are associated with iron transport, photosynthesis, or ATP synthesis. Comparing our data with three previous studies, we identified a core set of 28 genes involved in iron stress response. Among them were genes important for assimilation of inorganic carbon, suggesting a link between the carbon and iron regulatory networks. Nine of the 28 genes have unknown functions and constitute key targets for further functional analysis. Statistical and clustering analyses identified 10 small RNAs, 62 antisense RNAs, four 59UTRs, and seven intragenic elements as potential novel components of the iron regulatory network in Synechocystis. Hence, our genome-wide expression profiling indicates an unprecedented complexity in the iron regulatory network of cyanobacteria.
- Caracterização de patologias recorrentes na construção algarviaPublication . Laranja, Roberto; André, António; Braga, Alfredo Manuel Gonçalves SilvaO Laboratório de Construção e Estruturas (LCE) do Departamento de Engenharia Civil (DEC) do Instituto Superior de Engenharia da Universidade do Algarve realizou ao longo dos últimos anos, diversas peritagens técnicas a edifícios na região algarvia. Contam-se por várias dezenas as construções examinadas e são as ilações daí retiradas que constituem a base deste artigo. As peritagens têm sido realizadas nos vários tipos de construções, sobretudo a edifícios construídos nas décadas de 80 e 90 do séc. XX e providos duma estrutura reticulada de betão armado. A utilização da estrutura e equipamentos do LCE, tem permitido, através da realização de ensaios, quer “in situ” quer em laboratório, proceder a uma avaliação objetiva das patologias existentes. Entre as anomalias mais difundidas, refere-se as deficiências de projeto (sobretudo na omissão de pormenorização), manifestações de fissuração e humidade, e a deterioração do betão armado. As manifestações mais disseminadas de patologia são a ocorrência de fissuração, sobretudo de origem não estrutural e o aparecimento de humidades, que se traduz pela manifestação de eflorescências (e criptoflorescências), bolores, enodoamentos e desprendimentos de pintura. A nível estrutural também se identificaram alguns casos de fendilhação, embora o aspeto mais sintomático seja a deterioração do betão armado. Enquanto as anomalias anteriormente referidas serão comuns a edifícios, qualquer que seja a respetiva zona de implantação, a degeneração do betão armado tem uma particular incidência na zona costeira, sempre que a respetiva proteção não é suficientemente acautelada e a qualidade de construção não é a desejável. A agressividade ambiental que se faz sentir sobre a generalidade dos edifícios, assume especial relevância nas povoações costeiras de Monte Gordo, Quarteira, Albufeira, Armação de Pêra e Portimão, onde a construção para segunda habitação foi muito intensa e em alguns casos de qualidade duvidosa. Os ensaios realizados em edifícios localizados nessas povoações evidenciaram, além de profundidades de carbonatação muito elevadas, reveladoras da falta de compacidade e deficiência qualitativa do betão, teores de iões cloreto elevados, pelo ambiente marinho a que se encontram expostos. As peritagens técnicas que serviram de base a esta apresentação, constituem uma forma de apoio à comunidade, providenciando uma avaliação objetiva das deficiências construtivas e constituem um estímulo para melhorar o nível qualitativo da construção na região. Por outro lado, possibilitam a apresentação aos alunos do DEC (salvo a necessária garantia de confidencialidade) de casos de estudo reais, algumas vezes através da observação “in loco”, constituindo assim uma mais valia para a sua formação.
- Overwash hazard assessmentPublication . Rodrigues, B. A.; Matias, Ana; Ferreira, O.Overwash is a natural storm-related process that occurs when wave runup overcomes the dune crest. Because coastlines are globally occupied, overwash is a hazardous process and there is a need to identify vulnerable areas. This study proposes a method to detect overwash-prone areas in the Ancao peninsula, Portugal, and eventually outlines a vulnerability map. Dune base (D-LOW) and crest (D-HIGH) topography were surveyed. Three different storm scenarios (5-, 10- and 25- year return period storms) and associated waves and sea level were determined. According to these data, extreme wave runup (R-HIGH) was calculated by a parameterisation set for intermediate-reflective beaches. The maps for collision and overwash regimes were designed by comparing R-HIGH values with D-LOW and D-HIGH. Almost the entire dune base along the peninsula is vulnerable to collision regime. The overwash process was identified mainly along the tidal inlet hazard area and within the human-occupied portion of the beach, where overwash is expected to occur within 5 years of return period. The developed method considers the main overwash driving forces and proved to identify hazardous areas previously observed in the area. Occasional differences between modelled and observed overwash areas can be attributable to equipment errors, morphology interpretation subjectivity and maladjustments in runup parameterisation. Nevertheless, the method proved to be effective in reproducing the overall Ancao peninsula vulnerability and can be widely applied. Therefore, it is a simple and potentially important tool for coastal management that enables mitigation strategies for occupied coasts and assessment of geological and ecological consequences in natural areas.
- Submarine groundwater discharge in southern Portugal: Insights from stable isotope signaturesPublication . Veiga-Pires, C.; Aníbal, J.; Carvalho, L. F.; Rocha, C.Submarine Groundwater Discharges (SGD) occur almost all around the world and are considered to be significant contributors of high nutrient concentrations to coastal waters.
- Psicogeografias de Hong Kong: in mood for lovePublication . Silva, BrunoEste trabalho pretende analisar as características psicogeográficas de Hong Kong e determinar a sua influência no cinema desta região. Procura-se, acima de tudo, compreender as relações entre estas especificidades e as opções estéticas de Wong Kar-Way no filme In the mood for love (2000): a ausência de planos gerais; a ausência de luz natural; a ausência de privacidade das personagens; a sua obsessão pela comida e pelo cinema que, na década de 60, quando decorre a narrativa, tinha uma média anual de 90 milhões de espectadores.
- Point and fault rupture stochastic methods for generating simulated accelerograms considering soil effects for structural analysisPublication . Estêvão, João M. C.; Oliveira, Carlos SousaMany seismic codes such as the Eurocode 8 allow the use of simulated accelerograms for structural analysis, provided that the samples used are adequately qualified with regard to the seismogenetic features of the sources and to the soil conditions appropriate to the site. In the present work we studied the possibility of using stochastic methods for that purpose. In that context, two computer programs for stochastic ground motion simulation considering soil effects were developed: ACELGER based on a point source model, and SIMULSIS based on a finite fault model. Both programs were used to simulate the 1992 Landers earthquake for their validation. Simulation results obtained with these programs were compared between each other to better understand the influence of source fault plane geometry in structural response. Results seem to indicate that finite fault models are better options for structural analysis, because only with them it is possible to reproduce directivity effects and non stationary structural response observed with recorded accelerograms. SIMULSIS was also used to carry out the simulation of the 1980 Azores earthquake (January 1, 1980, Portugal) in two islands, with different local site conditions, which were compared with observed damages, to better understand the influence of soil geology in structural response, and showed that site effects have a major importance in structural behaviour.
- Fluid flow and interlinked feedback loops establish left-right asymmetric decay of Cerl2 mRNAPublication . Nakamura, Tetsuya; Saito, Daisuke; Kawasumi, Aiko; Shinohara, Kyosuke; Asai, Yasuko; Takaoka, Katsuyoshi; Dong, Fenglan; Takamatsu, Atsuko; A. Belo, José; Mochizuki, Atsushi; Hamada, HiroshiBreaking of left-right symmetry in mouse embryos requires fluid flow at the node, but the precise action of the flow has remained unknown. Here we show that the left-right asymmetry of Cerl2 expression around the node, a target of the flow, is determined post-transcriptionally by decay of Cerl2 mRNA in a manner dependent on its 3' untranslated region. Cerl2 mRNA is absent specifically from the apical region of crown cells on the left side of the node. Preferential decay of Cerl2 mRNA on the left is initiated by the leftward flow and further enhanced by the operation of Wnt-Cerl2 interlinked feedback loops, in which Wnt3 upregulates Wnt3 expression and promotes Cerl2 mRNA decay, whereas Cerl2 promotes Wnt degradation. Mathematical modelling and experimental data suggest that these feedback loops behave as a bistable switch that can amplify in a noise-resistant manner a small bias conferred by fluid flow.
- Joint use of data and modeling in coastal wave transformationPublication . Fortes, Conceicao Juana; Ferreira, Oscar; Silva, Paulo A.; Moura, Theo; Capitao, Rui; Amante, Luis; Vousdoukas, Michalis; Bezerra, MariaIn the framework of a research project entitled "BRISA-BReaking waves and Induced SAnd transport", a methodology was devised to characterize the waves joining together in-situ measurements and numerical wave propagation models. With this goal in mind, a number of in-situ measurements were made, for selected positions in front of Praia de Faro (South Portugal), during four days (25th to 28th March, 2009) by using different types of equipments (e.g., resistive wave gauges, pressure sensors, currentmeters and a new prototype pore pressure sensor using optical fibre). Wave records were obtained simultaneously offshore (at a water depth of 11.7 m below mean sea level, MSL) and at the surf and swash zones. The data processing and analysis were made by applying classical time domain techniques. Numerical simulations of the wave propagation between offshore and inshore for the measurement period were performed with two numerical models, a 1D model based on linear theory and a nonlinear Boussinesq-type model, COULWAVE, both forced by the measured offshore wave conditions of 27th March 2009. Comparisons between numerical results and field data for the pressure sensors placed in the surf and swash zones were made and discussed. This approach enables to evaluate the performance of those models to simulate those specific conditions, but also to validate the models by gaining confidence on their use in other conditions.
- Vasco Graça Moura: 50 anos de ficções e quase ficçõesPublication . Nogueira, AdrianaUma passagem pela ficção narrativa (contos e romances), de Vasco Graça Moura, no ano (2012) em que se comemoraram os 50 anos de vida literária deste poeta, tradutor, romancista, crítico, político, gestor, melómano.
- Normas para elaboração de relatórios técnicos e científicosPublication . Nunes, LuísEste trabalho pretende fornecer algumas regras orientadoras para a elaboração de trabalhos científicos e técnicos não periódicos sem pretender ser exaustivo, sendo antes um guia de consulta rápida. Este documento segue o estabelecido pelas Normas Portuguesas que se aplicam à formatação de documentos técnicos (IPQ 1968a; IPQ 1968b; IPQ 1969; IPQ 1986a; IPQ 1986b; IPQ 1989a; IPQ 1989b; IPQ 1993a; IPQ 1993b; IPQ 1994; IPQ 1995; IPQ 1998).