Role of the sediments of two tropical dam reservoirs in the flux of metallic elements to the water column

In tropical climates, the high rainfall and temperature, throughout the annual cycle, allow high leaching rates of metallic elements from the basin upstream, which accumulate in the reservoirs. However, the concentration of these elements in natural waters is usually lower than expected, due to the ease of adsorption and co-precipitation in solid phases. We have studied two tropical dam reservoirs in Brazil, Três Marias (Minas Gerais) and Tucuruí (Pará), with the aim of understanding the correlation between physical–chemical parameters of the water column, chemical and mineralogical characteristics of the accumulated material and the solubility, mobilization and precipitation of metals in reservoirs. Metals speciation performed in selected samples determined that metallic micronutrients are preferentially adsorbed or retained through precipitation/co-precipitation onto fine-size charged crystalline/amorphous Fe-oxides. Under the prevailing reducing and low pH conditions of the bottom reservoirs, some adsorbed metals (particularly Fe and Mn) are easily released from their metal bearing-phases and mobilized to the aqueous phase of sediments, which show high levels of soluble forms of these elements. However, the solubilization process and the release to the water column are not very extensive, as abundances of metals such as Fe, Mn, Zn and Cu in water are low, although increasing with dept

In vitro preliminary hemolytic studies of toxins from jellyfish Catostylus tagi

Poster presented at the 1st CiiEM Congress: "From Basic Sciences to Clinical Research". 27-28 November 2015, Egas Moniz, Caparica, PortugalEgas Moniz - Cooperativa de Ensino Superior CRL (Projects: EM-ZM 03: Preliminary studies on the capture and preservation conditions of a Portuguese medusa; EM-ZM-04: Studies on the utilization of Catostylus tagi in health sciences)

Preliminary studies on the extraction of phenolic compounds from olive leaves of Portuguese cultivars

Poster presented at the 2nd International Congress of CiiEM: “Translational Research and Innovation in Human in health Sciences”. Egas Moniz, Caparica, 11-13 June 2017Phenolic compounds of olive tree (Olea europaea) are considered one of the responsibles of the health-promoting of Mediterranean diet. Indeed, recent studies on isolated phenolic compounds have found a number of applications in increasing human immune response. The olive leaves, known to be rich in phenolic compounds, are a by-product of pruning and mechanical harvesting of olives. In the present work, started in November 2015, optimization in extraction and in component analysis has been achieved.N/

Inter-ethnic prejudice reduction in childhood : a common ingroup identity is not enough : the importance of the superordinate category type

This thesis examines, in the framework of the common ingroup identity model, the effectiveness of different types of superordinate category to reduce intergroup prejudice among White and Black Portuguese children. Specifically, we tested the effect of a superordinate category related to groups’ ethnic status (Portugal) and a superordinate category unrelated to groups’ ethnic status (School). We expected that the status-related superordinate category would emphasize the salience and significance of the ingroup-outgroup distinction, resulting in less positive intergroup evaluations. In this condition, we also expected both subgroups to perceive the higherstatus group (White) as more prototypical of the superordinate category than the lower-status group (Black). On the other hand, we expected that a status-unrelated superordinate category would shift attention away from the ingroup-outgroup distinction, resulting in more positive intergroup evaluations and more similar ingroup and outgroup prototypicality perception. These predictions were tested in three quasiexperimental studies (N = 575) with White and Black Portuguese children aged 9-10. Overall, our results indicate that the superordinate category School, compared to Portugal, resulted in more positive intergroup evaluations and a more balanced representation of the subgroups within the superordinate category, for both White and Black children. Moreover, recategorization and dual identity’s effects on prototypicality perceptions and intergroup evaluation were found to vary as a function of the type of superordinate category and groups’ ethnic status. These findings highlight the importance of considering the differential effects of the type of superordinate category in prejudice reduction research and interventions.Esta tese analisa, no âmbito do modelo da identidade endogrupal comum, a eficácia de diferentes tipos de categoria supraordenada na redução do preconceito intergrupal entre crianças Portuguesas Brancas e Negras. Especificamente, testámos o efeito de uma categoria supraordenada relacionada com o estatuto étnico dos grupos (Portugal) e de uma categoria supraordenada não-relacionada com o estatuto étnico dos grupos (Escola). Esperávamos que a categoria supraordenada relacionada com o estatuto enfatizasse a saliência e importância da distinção endogrupo-exogrupo, resultando em avaliações intergrupais menos positivas. Nesta condição, esperávamos também que ambos os subgrupos percepcionassem o grupo de alto-estatuto (Brancos) como mais prototípico da categoria supraordenada do que o grupo de baixo-estatuto (Negros). Por outro lado, esperávamos que a categoria supraordenada não-relacionada com o estatuto reduzisse o foco de atenção na distinção endogrupo-exogrupo, originando avaliações intergrupais mais positivas e uma percepção de maior semelhança entre a prototipicalidade do endogrupo e do exogrupo. Estas hipóteses foram testadas em três estudos quasi-experimentais (N = 575) com crianças Portuguesas, Brancas e Negras, com idades entre os 9 e os 10 anos. Globalmente, os resultados indicam que a categoria supraordenada Escola, em comparação com Portugal, originou avaliações intergrupais mais positivas a uma representação mais equilibrada dos subgrupos na categoria supraordenada, quer para as crianças Brancas quer para as crianças Negras. Além disso, os efeitos da recategorização e da dupla identidade na percepção de prototipicalidade e avaliação intergrupal variaram em função do tipo de categoria supraordenada e do estatuto étnico dos grupos. Estes resultados realçam a importância de se considerarem os efeitos diferenciados do tipo de categoria supraordenada na investigação sobre redução do preconceito e, também, na intervenção

High-Pressure CO2-H2O Mixture and Ammonia Technologies for Lignocellulosic Biomass Processing within Biorefinery Concept

The main purpose of this dissertation is to scrutinise the potential of two distinct high-pressure technologies - CO2/H2O mixture and ammonia – for lignocellulosic biomass processing following the biorefinery concept. High-pressure CO2/H2O mixture took benefits from the formation of in-situ carbonic acid and involved the integration of both pre-treatment and hydrolysis steps. Due to its acidic effect, this technology was able to selectively hydrolyse the hemicellulosic fraction of biomass producing C5-oligomeric sugar-rich aqueous stream. Later, the C5-sugars present in this stream were successfully converted into furfural with high yield and selectivity using the same catalytic effect of high-pressure mixture of CO2/H2O. Additionally, the leftover materials enriched in cellulose demonstrated to be highly susceptible for enzymatic hydrolysis leading the production of highly concentrated solution of upgradable glucose. High-pressure ammonia relied on the development of a new ammonia-based technology called “Compacted Biomass with Reduced Ammonia” to pre-treat pelletised biomass, at reduced ammonia loadings. This process combined the advantages of conversion of native crystalline cellulose Iβ into highly digestible cellulose III and the benefits of ammonolysis of cell wall ester cross-links. Besides, the proposed process allowed obtaining fermentable sugars, either C5 or C6-sugars, and ethanol yields comparable to industrially relevant technologies i.e. AFEXTM (Ammonia Fiber Expansion) and steam explosion. Additionally, the proposed approach demonstrated to be a feedstock-independent technology capable to handle different types of biomasses, regardless of their macromolecular composition and morphological structure, to produce high yields of fermentable sugars. Both explored technologies demonstrated to be highly effectives for lignocellulosic biomass valorisation, showcasing their potential as sustainable technologies applicable in the biorefinery approach

Preliminary studies on the extraction of Hydroxytyrosol and derivatives from olive leaves of Portuguese cultivars

Poster apresentado no XIII Encontro de Química dos Alimentos. 14-16 Setembro 2016, Porto, PortugalN/

Identification and Characterization of the Transcriptional Regulator ChrB in the Chromate Resistance Determinant of Ochrobactrum tritici 5bvl1

Ochrobactrum tritici 5bvl1 is able to resist to high concentrations of chromate through the expression of an inducible chromate-resistant determinant, found in a mobile element (TnOtChr), which carries the genes, chrB, chrA, chrC and chrF. The regulation of chr operon present in TnOtChr, which is controlled by a transcriptional regulator, ChrB, was characterized in the current work. Fusions of chr promoter, or chr promoter and chrB gene, upstream of a gfp reporter gene, identified the most probable promoter sequence within the tnpR-chrB intergenic region. This region contains an AT-rich imperfect inverted repeat sequence, which overlaps a part of the 210 sequence. The results of the in vitro DNA-binding assays with purified ChrB (His- or no-tagged) showed that the protein binds directly to the chr promoter region. In order to identify the ChrB functional domain for sensing chromate stress and for DNA-binding, site-directed mutagenesis of ChrB was performed. Among several single amino acid mutants, three mutants (R180; R187 and H229) prevented chromate induction without any modification to the protein’s stability. Interestingly, two ChrB mutants (R18 and R23) were constitutively active, regardless of chromate stress conditions, indicating that the residues most probably belong to the protein-DNA binding site. As such, the ChrB was classified as a transcriptional regulator that recognizes a specific DNA sequence, regulating the expression of a chromate resistance determinant.This work was funded by Fundação para a Ciência e Tecnologia (FCT) under the PTDC/MAR/109057/2008 project. Rita Branco was supported by a grant, SFRH/BPD/48330/2008, from FCT

Relação instrutor de exercício físico e praticantes desportivos: Teoria, investigação e intervenção

[Excerto] A atividade física em geral e a prática de exercício físico (EF) em particular, são consideradas indicadores positivos de um estilo de vida saudável. Pelo contrário, a inatividade física é a principal causa de uma qualidade de vida empobrecida, doenças e incapacidades e até mesmo a morte (Brehem, 2004). Nos últimos vinte e cinco anos, as maiores organizações de saúde publica, nomeadamente American Heart Association (AHA), a American College of Sports Medicine (ACSM, 2009), a Centers for Disease Control and Prevention (CDC) e o National Institutes of Health (NIH), assumiram como principal preocupação os benefícios de um estilo de vida ativo e as consequências de um estilo de vida sedentário (Marcus & Forsyth, 2009). Neste sentido, é incontestável que o estilo de vida inativo ou sedentário apresenta um impacto particularmente negativo na saúde individual e na saúde pública, para além representar um enorme encargo económico a nível mundial (Blair, 2009; Hardman & Stensel, 2009; Kohl et al., 2012). [...