Ensinar Ciência no pré-escolar. Contributos para aprendizagens de outras áreas/domínios curriculares. Relato de experiências realizadas em jardins de infância

O ensino das ciências deve começar no jardim de infância, através de uma abordagem transversal em que se evidencia o papel das ciências e em particular das actividades experimentais, como contexto privilegiado para o desenvolvimento das outras áreas do currículo. Na comunicação oral serão apresentados diversos exemplos de actividades científicas realizadas em salas de jardim de infância, em que se privilegia uma abordagem transversal dos conteúdos, mobilizadora de conhecimentos, capacidades e atitudes de diferentes áreas e domínios (matemática, comunicação, expressões plástica e dramática, formação pessoal e social)

Teacher and peer reports on preschoolers’ sociometric popularity

This study investigated the association between preschool children’s sociometric popu-larity obtained from peer sociometric nominations and from teachers’ classifications. A total of 1535 children (731 girls and 804 boys), aged between 34 and 89.6 months (M = 61.96, SD = 8.91), and 89 teachers participated in the study. The association between reports from the two sources, although not independent, was weak, with teachers perceiving more children as popular and fewer children as rejected. Teacher and peer classifications were similarly asso-ciated with social skills and behavior problems. Sociometric popularity obtained from teachers, but not from peers, was associated with children’s age and verbal competence. Overall, findings suggest that traditional peer sociometric nominations, even at early ages, are not replaceable by teachers’ classifications of children’s sociometric popularity.info:eu-repo/semantics/acceptedVersio

Carbon sequestration and nutrient reserves under different land use systems.

ABSTRACT-This study evaluated the contribution of agroforestry (AFS) and traditional systems to carbon sequestration and nutrient reserves in plants, litter and soil. The study was carried out in the semiarid region of Brazil in a long-term experiment on an experimental farm of the goat and sheep section of the Brazilian Agricultural Research Corporation (Embrapa). Two agroforestry systems were investigated: agrosilvopastoral (ASP) and forest-pasture areas (SP) as well as traditional agriculture management (TM), two areas left fallow after TM (six fallow years - F6 and nine fallow years - F9) and one area of preserved Caatinga vegetation (CAT). Soil, litter and plants were sampled from all areas and the contents of C, N, P, K, Ca and Mg per compartment determined. The AFS (ASP and SP) had higher nutrient stocks than the traditional and intermediate stocks compared to the preserved Caatinga. In the ASP, a relevant part of the nutrients extracted by crops is returned to the system by constant inputs of litter, weeding of herbaceous vegetation and cutting of the legume crops. After fallow periods of six and nine years, carbon and nutrient stocks in the compartments soil, litter and herbaceous plants were similar to those of the preserved Caatinga (CAT), but still lower than under natural conditions in the woody vegetation. RESUMO-Objetivou-se conhecer a contribuição de sistemas agroflorestais (SAFs) e tradicionais para o sequestro de carbono e a reserva de nutrientes presentes nas plantas, serrapilheira e solo. O estudo foi realizado na região semiárida brasileira, em experimento de longa duração realizado na Fazenda Experimental da Embrapa Caprinos e Ovinos. Estudaram-se dois sistemas agroflorestais: agrossilvipastoril (ASP) e silvipastoril (SP) e um tradicional (AG), sendo também utilizadas duas áreas sob pousio após o manejo tradicional (seis anos - F6 e nove anos F9) e uma área de Caatinga conservada (CAT). Nessas áreas, foram realizadas coletas de solo, serrapilheira e plantas, sendo os teores de C, N, P, K, Ca e Mg quantificados em cada um desses compartimentos. Os SAFs (ASP e SP) apresentaram estoques de nutrientes superiores ao tradicional e intermediários em relação à Caatinga conservada. No ASP, grande parte dos nutrientes extraídos pelas colheitas volta ao sistema por meio das entradas via serrapilheira, capinas das herbáceas e poda das leguminosas. Os estoques no solo, na serrapilheira e nas plantas herbáceas após os períodos de pousio de seis e nove anos foram semelhantes à Caatinga conservada, porém os estoques do estrato arbóreo foram inferiores à condição natural

Highly selective and sensitive detection of toxic metals by fluorescent Bicyclic Calix[4]arene-based sensors

Este trabalho foi financiado pelo Concurso Anual para Projetos de Investigação, Desenvolvimento, Inovação e Criação Artística (IDI&CA) 2016 do Instituto Politécnico de Lisboa. Código de Referência IPL/2016/NoSeMeTox_ISELDevelopment of fast and portable chemosensors for trace detection of toxic metals, in particular those which are mostly present in the environment due to natural phenomenon and human activities (e.g. cadmium, mercury and lead), is a challenging area of current research.1 Calixarenes are one of the most widespread scaffolds in host-guest chemistry because of their rigid structures, which make them perfect candidates for complexation studies with ions and neutral molecules. Metal ions commonly bind at the lower rim of the calixarene moiety. Host-guest interaction can be enhanced by proper choice of additional binding sites containing nitrogen, oxygen, sulfur or a combination of them, and specifically designed calixarene architectures. Exploring the inherent capabilities of certain fluorescent calixarene-based compounds for establishing strong host:guest interactions, several sensing materials have been developed and tested by us towards the detection of neutral molecular species.2. We report in this communication the chemosensing ability of CALIX-OCP-CBZ and CALIX-OCP (Scheme 1) towards the detection of toxic metals, either by using the sensing element in fluid phase or solid state.info:eu-repo/semantics/publishedVersio

Modeling and Simulation of PV Panel Under Different Internal and Environmental Conditions with Non-constant Load

This paper focuses on PV power conversion under different internal and environmental conditions with non-constant load, connected to a smart grid system. Due to environmental conditions, the PV system is a non-linear system and difficult to predict the power conversion. In the aspect of internal variables, it includes the five parameters of the single diode solar cell model identify their sensitivity through error function. It also identifies the relation between environmental conditions, mainly: irradiance, temperature and wind speed. The modeling and computational simulation with laboratory work identify the effects of internal and environmental effect on the system. The model gives details about the sensitivity of each environmental condition using error function. The work includes the decrease of energy conversion by the solar panel as a function of time due to the shadow effect that affects its performance. Besides these, a smart system is introduced as a DAQ system in laboratory environment to get in real time the power conversion value with the P-V and I-V characteristics of the PV panel

The long exercise test as a functional marker of periodic paralysis

Aims: The aim of this study was to evaluate the sensitivity of the long exercise test (LET) in the diagnosis of periodic paralysis (PP) and assess correlations with clinical phenotypes and genotypes. // Methods: From an unselected cohort of 335 patients who had an LET we analyzed 67 patients with genetic confirmation of PP and/or a positive LET. // Results: 32/45 patients with genetically confirmed PP had a significant decrement after exercise (sensitivity of 71%). Performing the short exercise test before the LET in the same hand confounded results in four patients. Sensitivity was highest in patients with frequent (daily or weekly) attacks (8/8, 100%), intermediate with up to monthly attacks (15/21, 71%) and lowest in those with rare attacks (9/16, 56%) (p = .035, Mann–Whitney U-test). Patients with a positive LET without confirmed PP mutation comprised those with typical PP phenotype and a group with atypical features. // Discussion: In our cohort, the LET is strongly correlated with the frequency of paralytic attacks suggesting a role as a functional marker. A negative test in the context of frequent attacks makes a diagnosis of PP unlikely but it does not rule out the condition in less severely affected patients

Effect of autochthonous starter cultures in the production of "Paio", a traditional Portugese dry-cured sausage

En los países mediterráneos, como Portugal, los embutidos curados tradicionales son muy apreciados. A menudo se siguen fabricando en pequeñas unidades de procesamiento, de acuerdo con los procedimientos tradicionales. Los objetivos del presente estudio fueron evaluar el efecto de diferentes cultivos iniciadores y su concentración óptima, para reducir la carga microbiana y las aminas biogénicas en productos finales, con el objetivo de mejorar la seguridad de los embutidos sin deteriorar la aceptación sensorial. pH, aw, perfil microbiológico, aminas biogénicas, análisis del perfil de color y textura fueron evaluados. Las cepas y las concentraciones a utilizar, se seleccionaron en base a resultados previos: Staphylococcus xylosus, Lactobacillus sakei y una cepa de levadura a una concentración de 106 ufc / g de masa de carne cada una, se añadió 0,25% de dextrosa. Siempre se utilizó un lote control sin cultivos iniciadores. Los valores de aw fueron menores en los embutidos inoculados. En general, los valores de pH fueron ligeramente superiores en los embutidos inoculados. El tratamiento con L. sakei solo fue el más efectivo en la reducción del nivel de contaminación con L. monocytogenes, sin embargo este efecto parece perderse en cultivos mixtas. La inoculación, disminuyó generalmente el contenido de putrescina, de cadaverina y de tiramina. La inoculación de levadura parece contribuir al color más oscuro de los Paios. Con respecto a la textura, el Paio control demostró valores más altos de la dureza

The usefulness of ecotoxicological tools to improve the assessment of water bodies in a climate change reality

This study aimed to analyse the added value of using ecotoxicological tools to complement and improve the assessment of natural water bodies status, in situations of climate change, with a higher frequency of extreme events as floods or droughts. Four water bodies of streams in the Guadiana Basin (Álamos, Amieira, Lucefécit, Zebro) were studied in 2017 and 2018 and classified based on the Water Framework Directive (WFD) parameters: Biological Quality Element - Phytobenthos (diatoms), General chemical and physicochemical elements, Specific pollutants, and Priority Substances. Complementarily, bioassays (including lethal and sublethal parameters) were carried out with organisms of different trophic levels: (i) the bacteria Aliivibrio fischeri; (ii) the microalgae Pseudokirchneriella subcapitata; (iii) the crustaceans Daphnia magna, Thamnocephalus platyurus and Heterocypris incongruens. A classification system with 5 scores was developed, permitting to classify water bodies from non-toxic (EC50 > 100 %; growth and feeding rate > 80 %; blue) to highly toxic (EC50 < 10 %; growth and feeding rate < 10 %; red). The comparison between the classification based on the WFD parameters and on ecotoxicological endpoints showed similar results for 71 % of the samples, and significant positive Pearson correlations were detected between the diatom-based Specific Polluosensitivity Index (SPI) and EC50V.fisheri, the algae growth rate and Shannon diversity index. These results indicate that when the biological quality elements cannot be used (namely under drought or flooding conditions) the application of ecotoxicological bioassays may be a good alternative. Further, when ecotoxicological parameters were included, an increase of worse classifications (Bad and Poor) was observed, revealing an improvement in the sensitivity of the classification, mainly in presence of specific and priority substances. So, the ecotoxicological analysis appears to provide useful information regarding the potential presence of both known and unknown contaminants at concentrations that cause biological effects (even within the WFD limits), in agreement with several authors that have already suggested its use in biomonitoring