Phytoplankton dynamics in relation to seasonal variability and upwelling and relaxation patterns at the mouth of Ria de Aveiro (West Iberian Margin) over a four-year period

From June 2004 to December 2007, samples were weekly collected at a fixed station located at the mouth of Ria de Aveiro (West Iberian Margin). We examined the seasonal and inter-annual fluctuations in composition and community structure of the phytoplankton in relation to the main environmental drivers and assessed the influence of the oceano-graphic regime, namely changes in frequency and intensity of upwelling events, over the dynamics of the phytoplankton assemblage. The samples were consistently handled and a final subset of 136 OTUs (taxa with relative abundance > 0.01%) was subsequently submitted to various multivariate analyses. The phytoplankton assemblage showed significant changes at all temporal scales but with an overriding importance of seasonality over longer-(inter-annual) or shorter-term fluctuations (upwelling-related). Sea-surface temperature, salinity and maximum upwelling index were retrieved as the main driver of seasonal change. Seasonal signal was most evident in the fluctuations of chlorophyll a concentration and in the high turnover from the winter to spring phytoplankton assemblage. The seasonal cycle of production and succession was disturbed by upwelling events known to disrupt thermal stratification and induce changes in the phytoplankton assemblage. Our results indicate that both the frequency and intensity of physical forcing were important drivers of such variability, but the outcome in terms of species composition was highly dependent on the available local pool of species and the timing of those events in relation to the seasonal cycle. We conclude that duration, frequency and intensity of upwelling events, which vary seasonally and inter-annually, are paramount for maintaining long-term phytoplankton diversity likely by allowing unstable coexistence and incorporating species turnover at different scales. Our results contribute to the understanding of the complex mechanisms of coastal phytoplankton dynamics in relation to changing physical forcing which is fundamental to improve predictability of future prospects under climate change.Portuguese Foundation for Science and Technology (FCT, Portugal) [SFRH/BPD/ 94562/2013]; FEDER funds; national funds; CESAM [UID/AMB/50017]; FCT/MEC through national funds; FEDERinfo:eu-repo/semantics/publishedVersio

A smart pipe energy harvester excited by fluid flow and base excitation

This paper presents an electromechanical dynamic modelling of the partially smart pipe structure subject to the vibration responses from fluid flow and input base excitation for generating the electrical energy. We believe that this work shows the first attempt to formulate a unified analytical approach of flow-induced vibrational smart pipe energy harvester in application to the smart sensor-based structural health monitoring systems including those to detect flutter instability. The arbitrary topology of the thin electrode segments located at the surface of the circumference region of the smart pipe has been used so that the electric charge cancellation can be avoided. The analytical techniques of the smart pipe conveying fluid with discontinuous piezoelectric segments and proof mass offset, connected with the standard AC–DC circuit interface, have been developed using the extended charge-type Hamiltonian mechanics. The coupled field equations reduced from the Ritz method-based weak form analytical approach have been further developed to formulate the orthonormalised dynamic equations. The reduced equations show combinations of the mechanical system of the elastic pipe and fluid flow, electromechanical system of the piezoelectric component, and electrical system of the circuit interface. The electromechanical multi-mode frequency and time signal waveform response equations have also been formulated to demonstrate the power harvesting behaviours. Initially, the optimal power output due to optimal load resistance without the fluid effect is discussed to compare with previous studies. For potential application, further parametric analytical studies of varying partially piezoelectric pipe segments have been explored to analyse the dynamic stability/instability of the smart pipe energy harvester due to the effect of fluid and input base excitation. Further proof between case studies also includes the effect of variable flow velocity for optimal power output, 3-D frequency response, the dynamic evolution of the smart pipe system based on the absolute velocity-time waveform signals, and DC power output-time waveform signals

Avaliação da ingestão de nutrientes de crianças de uma creche filantrópica: aplicação do Consumo Dietético de Referência Assessment of nutrients intake of children in a charity daycare center: application of Dietary Reference Intake

OBJETIVOS: comparar a adequação aparente da ingestão dos nutrientes utilizando os valores de referência "Consumo Dietético de Referência" (Dietary Reference Intake-DRIs) de 35 crianças de uma creche filantrópica, em dois momentos, no ato da matrícula (momento 1) e após seis meses de freqüência na creche (momento 2). MÉTODOS: A avaliação sócio-demográfica foi realizada através de questionário abordando renda, escolaridade, condições de moradia e saneamento básico. Para avaliação do consumo alimentar, no ato da matrícula, a história dietética foi determinada em entrevista com o responsável, com o propósito de obter informações sobre consumo habitual da criança na sua residência. Após o período de seis meses foi utilizado o método de pesagem direta de alimentos (na creche) complementando com o consumo alimentar da criança na residência. A análise dos nutrientes como proteínas, ferro, cálcio e vitamina C, além das fibras alimentares, foi realizada através um programa computacional. Para comparar a adequação dos nutrientes nos dois momentos do estudo utilizou-se o teste t de Student para dados pareados (p < 0,05). RESULTADOS: observou-se que ocorreu uma melhora significativa no consumo médio de nutrientes e de fibras alimentares das crianças, após seis meses de frequência na creche. Chama atenção que nenhuma criança atingiu o nível de adequação de fibras alimentares nos dois momentos do estudo, apesar da diferença significativa. CONCLUSÕES: os resultados sugerem que as creches podem ter um importante papel na melhora do estado nutricional de crianças de estratos sociais menos favorecidos.<br>OBJECTIVES: to compare nutrients intake apparent adequacy through reference values of Dietary Reference Intake (DRIs) of 35 children of a charity daycare center in two instances, when they enrolled (instance 1) and six months after (instance 2). METHODS: socio-demographic assessment was performed through a questionnaire collecting information pertaining to income, school level, living conditions and basic sanitation. To assess food consumption at enrollment, dietary history was informed through an interview with the parent, family member or guardian on the usual intake of the child at home. Following a six month period the weighed food record method (in the daycare center) was performed complemented by the food intake of the child at home. Nutrient analysis such as proteins, iron, calcium and vitamin C in addition to food fibers was performed by specific software. To compare nutrients' adequacy in the two instances of the study the paired Student test (t) (p < 0.05) was used. RESULTS: a significant improvement in the median intake for all nutrients and fiber six moths after child's attendance to the daycare center was determined. No child reached the level of fiber apparent adequacy of the ingestion at the two moments of the study, despite the significant difference. CONCLUSIONS: results suggest that daycare centers can have an important role in the improvement of lower income children nutritional status

Direct AKAP-mediated protein-protein interactions as potential drug targets

A-kinase-anchoring proteins (AKAPs) are a diverse family of about 50 scaffolding proteins. They are defined by the presence of a structurally conserved protein kinase A (PKA)-binding domain. AKAPs tether PKA and other signalling proteins such as further protein kinases, protein phosphatases and phosphodiesterases by direct protein-protein interactions to cellular compartments. Thus, AKAPs form the basis of signalling modules that integrate cellular signalling processes and limit these to defined sites. Disruption of AKAP functions by gene targeting, knockdown approaches and, in particular, pharmacological disruption of defined AKAP-dependent protein-protein interactions has revealed key roles of AKAPs in numerous processes, including the regulation of cardiac myocyte contractility and vasopressin-mediated water reabsorption in the kidney. Dysregulation of such processes causes diseases, including cardiovascular and renal disorders. In this review, we discuss AKAP functions elucidated by gene targeting and knockdown approaches, but mainly focus on studies utilizing peptides for disruption of direct AKAP-mediated protein-protein interactions. The latter studies point to direct AKAP-mediated protein-protein interactions as targets for novel drugs