A construção de significado na aprendizagém da matematica

Nesta comunicação, darei a conhecer parte do estudo que conduzi no âmbito do mestrado em Informática e Educação, no que respeita à natureza da compreensão desenvolvida pelos alunos no contexto da aula de Matemática. A investigação teve como objectivo compreender e analisar o significado matemático, construído pelos alunos, em interacção social, focando a utilização do computador em actividades de construção geométrica.

Educação (formação) de professores e alunos

Vários estudos centram-se no desenvolvimento profissional dos professores, nos seus percursos de formação e envolvimento em projectos de inovação, nomeadamente os que fazem recurso às TIC, aproveitando a sua versatilidade e potencial pedagógico. No âmbito do programa Nónio-Século XXI, vários professores têm desenvolvido um conjunto de experiências educativas em espaços diversificados como a sala de aula, os Clubes ou os Centros de Recursos. O registo destas experiências profissionais constitui um enorme potencial de material pedagógico e didáctico que, para além de valorizar o papel dos actores nesse processo, pode permitir uma reflexão sobre as práticas. No contexto do Projecto Àbolina (http://www.ese.ips.pt/abolina/index.html) temos vindo a disponibilizar um espaço com conteúdos em português, ‗memória viva‘ de algumas experiências significativas do quotidiano dos principais actores deste desafio colectivo que possam constituir fonte de ideias e recursos educativos para os professores, incentivando os processos de discussão e partilha de experiências. Assim, partindo de um relato de colegas da EB 2,3 de Aranguez — Setúbal que incide na formação de alunos monitores no Centro de Recursos, abrimos um Fórum subordinado a este tema, considerando que as dimensões da comunicação e da partilha/reflexão constituem etapas fundamentais no desenvolvimento profissional dos professores. Da polémica surgida daremos conta na comunicação, discutindo as concepções pedagógicas a este projecto de formação de alunos monitores, na sua relação com o desenvolvimento de competências gerais/transversais nos alunos, nomeadamente com a partilha de responsabilidades e o desenvolvimento da autonomia.

Stratification of the earth beneath the Azores from P and S receiver functions

Seismic recordings of IRIS/IDA/GSN station CMLA and of several temporary stations in the Azores archipelago are processed with P and S receiver function (PRF and SRF) techniques. Contrary to regional seismic tomography these methods provide estimates of the absolute velocities and of the Vp/Vs ratio up to a depth of similar to 300 km. Joint inversion of PRFs and SRFs for a few data sets consistently reveals a division of the subsurface medium into four zones with a distinctly different Vp/Vs ratio: the crust similar to 20 km thick with a ratio of similar to 1.9 in the lower crust, the high-Vs mantle lid with a strongly reduced VpNs velocity ratio relative to the standard 1.8, the low-velocity zone (LVZ) with a velocity ratio of similar to 2.0, and the underlying upper-mantle layer with a standard velocity ratio. Our estimates of crustal thickness greatly exceed previous estimates (similar to 10 km). The base of the high-Vs lid (the Gutenberg discontinuity) is at a depth of-SO km. The LVZ with a reduction of S velocity of similar to 15% relative to the standard (IASP91) model is terminated at a depth of similar to 200 km. The average thickness of the mantle transition zone (TZ) is evaluated from the time difference between the S410p and SKS660p, seismic phases that are robustly detected in the S and SKS receiver functions. This thickness is practically similar to the standard IASP91 value of 250 km. and is characteristic of a large region of the North Atlantic outside the Azores plateau. Our data are indicative of a reduction of the S-wave velocity of several percent relative to the standard velocity in a depth interval from 460 to 500 km. This reduction is found in the nearest vicinities of the Azores, in the region sampled by the PRFs, but, as evidenced by SRFs, it is missing at a distance of a few hundred kilometers from the islands. We speculate that this anomaly may correspond to the source of a plume which generated the Azores hotspot. Previously, a low S velocity in this depth range was found with SRF techniques beneath a few other hotspots.

Cape Verde hotspot from the upper crust to the top of the lower mantle

We investigate the crust, upper mantle and mantle transition zone of the Cape Verde hotspot by using seismic P and S receiver functions from several tens of local seismograph stations. We find a strong discontinuity at a depth of similar to 10 km underlain by a similar to 15-km thick layer with a high (similar to 1.9) Vp/Vs velocity ratio. We interpret this discontinuity and the underlying layer as the fossil Moho, inherited from the pre-hotspot era, and the plume-related magmatic underplate. Our uppermost-mantle models are very different from those previously obtained for this region: our S velocity is much lower and there are no indications of low densities. Contrary to previously published arguments for the standard transition zone thickness our data indicate that this thickness under the Cape Verde islands is up to similar to 30 km less than in the ambient mantle. This reduction is a combined effect of a depression of the 410-km discontinuity and an uplift of the 660-km discontinuity. The uplift is in contrast to laboratory data and some seismic data on a negligible dependence of depth of the 660-km discontinuity on temperature in hotspots. A large negative pressure-temperature slope which is suggested by our data implies that the 660-km discontinuity may resist passage of the plume. Our data reveal beneath the islands a reduction of S velocity of a few percent between 470-km and 510-km depths. The low velocity layer in the upper transition zone under the Cape Verde archipelago is very similar to that previously found under the Azores and a few other hotspots. In the literature there are reports on a regional 520-km discontinuity, the impedance of which is too large to be explained by the known phase transitions. Our observations suggest that the 520-km discontinuity may present the base of the low-velocity layer in the transition zone. (C) 2011 Elsevier B.V. All rights reserved.

Fabrication of Three-Dimensional Dendritic Ni-Co Films By Electrodeposition on Stainless Steel Substrates

Co-deposition of nickel and cobalt was carried out on austenitic stainless steel (AISI 304) substrates by imposing a square waveform current in the cathodic region. The innovative procedure applied in this work allows creating a stable, fully developed, and open porous three-dimensional (3D) dendritic structure, which can be used as electrode for redox supercapacitors. This study investigates in detail the influence of the applied current density on the morphology, mass, and chemical composition of the deposited Ni-Co films and the resulting 3D porous network dendritic structure. The morphology and the physicochemical composition were studied by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (W). The electrochemical behavior of the materials was evaluated by cyclic voltammetry (CV). The results highlight the mechanism involved in the coelectrodeposition process and how the lower limit current density tailors the film composition and morphology, as well as its electrochemical activity.

Nanofiltration of surface water for the removal of endocrine disruptors

The assessment of surface water nanofiltration (NF) for the removal of endocrine disruptors (EDs) Nonylphenol Ethoxylate (IGEPAL), 4-Nonylphenol (NP) and 4-Octylphenol (OP) was carried out with three commercial NF membranes - NF90, NF200, NF270. The permeation experiments were conducted in laboratory flat-cell units of 13.2 x 10(-4) m(2) of surface area and in a DSS Lab-unit M20 with a membrane surface area of 0.036 m2. The membranes hydraulic permeabilities ranged from 3.7 to 15.6 kg/h/m(2)/bar and the rejection coefficients to NaCl, Na2SO4 and Glucose are for NF90: 97%, 99% and 97%, respectively; for NF200: 66%, 98% and 90%, respectively and for NF270: 48%, 94% and 84%, respectively. Three sets of nanofiltration experiments were carried out: i) NF of aqueous model solutions of NP, IGEPAL and OP running in total recirculation mode; ii) NF of surface water from Rio Sado (Settibal, Portugal) running in concentration mode; iii) NF of surface water from Rio Sado inoculated with NP, IGEPAL and OP running in concentration mode. The results of model solutions experiments showed that the EDs rejection coefficients are approximately 100% for all the membranes. The results obtained for the surface water showed that the rejection coefficients to natural organic Matter (NOM) are 94%, 82% and 78% for NF90, NF200 and NF 270 membranes respectively, with and without inoculation of EDs. The rejection coefficients to EDs in surface water with and without inoculation of EDs are 100%, showing that there is a fraction of NOM of high molecular weight that retains the EDs in the concentrate and that there is a fraction of NOM of low molecular weight that permeates through the NF membranes free of EDs.

Formação contínua e desenvolvimento institucional: desafios e respostas

A Escola Superior de Educação de Lisboa (ESELx) tem um largo historial ao serviço da formação contínua de professores. Neste artigo, pretende-se dar conta do trabalho desenvolvido e a desenvolver nesse âmbito. Apresentase, primeiro, o percurso seguido, equacionando os momentos mais significativos e que se constituíram como pontos de viragem ao longo do tempo, nomeadamente, a adesão ao Programa Foco, a constituição da ESELx como Centro de Formação e a colaboração da ESELx na implementação dos Programas Nacionais de Formação Contínua nas áreas da Matemática, Português e Ensino Experimental das Ciências. Seguidamente, analisam-se as implicações que a formação contínua tem tido na vida da instituição e perspetiva-se a estratégia a seguir no futuro, entendendo a formação contínua como um fator de desenvolvimento institucional.

Competências em língua portuguesa à saída da licenciatura: o caso da licenciatura em Educação Básica da ESELx (2010-11)

O presente artigo tem como objetivo geral analisar o desempenho dos alunos da licenciatura em Educação Básica da Escola Superior de Educação de Lisboa na prova de língua portuguesa de acesso ao 2º Ciclo de estudos, no ano letivo de 2010-11. Em concreto, procurar-se-á: (i) caracterizar os candidatos; (ii) identificar as áreas de maior (in)sucesso no âmbito das competências em avaliação (leitura, escrita e conhecimento linguístico).

O impacto da mediatização nas capitais europeias da cultura: o caso das cidades Porto 2001 e Guimarães 2012

Artigo baseado na comunicação proferida no XIII Congreso Internacional Ibercom: comunicação e esferas de poder, realizado na Universidade de Santiago de Compostela, Santiago de Compostela, Espanha, 29 -31 maio 2013

Newspaper coverage impact on cultural events: Porto 2001 and Guimarães 2012: European Cultural Capitals

Artigo baseado na comunicação proferida no 1st International Symposium on Media Studies, realizado na Akdeniz Universitesi Yayınları, Antalya, Turquia, 21-23 de novembro de 2013

The Portuguese transition to democracy

On 25 April 1974 the Armed Forces Movement (MFA – Movimento das Forças Armadas) rose against the dictatorial regime that had governed Portugal for 48 years. This event was the beginning of a turbulent transition process that was to culminate in the approval of a new constitution in April 1976 and in the instauration of a Western style pluralist democracy. There are many political scientists and historians who note the original and unexpected nature of this transition; however, there are very many different interpretations with respect to the roles played by each of the actors in the process: the armed forces, the parties and political movements and the social forces/movements. The aim of this paper is to clarify this matter through an examination of the principal events of the revolution.

Comunicación: una herencia de la Escuela de Sociología de Chicago

La Escuela de Chicago de pensamiento social, desde sus fundadores de finales del siglo XIX a las grandes figuras de las primeras décadas del siglo XX, es un referente imprescindible por sus estudios, considerados actualmente parte del canon sociológico, sobre la ecología humana, la ciudad, la inmigración, las relaciones étnicas, la delincuencia, el control social y el self humano. Este ensayo sostine que en esta escuela se encuentra una reflexión pioneira y una invetigación de gran relevancia sobre los temas de la comunicación y los medios de comunicación en la sociedad, habiendo contribuído a convertirlos en un centro de atención para la teoría social y la sociología.

Teor crítico de cloretos para iniciação da corrosão do aço no betão: influência do estado de superfície da armadura

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Química e Biológica - Processos Químicos

Reflexões de introdução

O presente e-book tem por objetivo registar as contribuições de um conjunto de docentes e investigadores oriundos de várias universidades e politécnicos, aquando da realização do 1º Encontro do Grupo de Trabalho de Comunicação Organizacional e Institucional da SOPCOM, realizado na Universidade do Minho em Julho de 2013. O tema central do debate versou sobre a questão da “divergência ou convergência entre os conceitos da Comunicação Organizacional e das Relações Públicas”, que causa sempre acesa polémica e opiniões diversas. Ambos os conceitos têm falhado em chegar a uma definição consensual em termos dos seus propósitos fundamentais, do seu domínio e do seu âmbito, quer em termos práticos como teóricos. Neste texto procuram-se respostas e fazem-se reflexões na tentativa de aproximar as visões da academia.

Generalizing repeating patterns: a study with children aged four

This paper presents part of a study that aimed to understand how the emergence of algebraic thinking takes place in a group of four-year-old children, as well as its relationship to the exploration of children‘s literature. To further deepen and guide this study the following research questions were formulated: (1) How can children's literature help preschoolers identify patterns?; (2) What strategies and thinking processes do children use to create, analyze and generalize repeating and growing patterns?; (3) What strategies do children use to identify the unit of repeat of a pattern? and (4) What factors influence the identification of patterns? The paper focuses only on the strategies and thinking processes that children use to create, analyze and generalize repeating patterns. The present study was developed with a group of 14 preschoolers in a private school in Lisbon, and it was carried out with all children. In order to develop the research, a qualitative research methodology under the interpretive paradigm was chosen, emphasizing meanings and processes. The researcher took the dual role of teacher-researcher, conducting the study with her own group and in her own natural environment. Participant observation and document analysis (audio and video recordings, photos and children productions) were used as data collection methods. Data collection took place from October 2013 to April 2014. The results of the study indicate that children master the concept of repeating patterns, and they are able to identify the unit of repeat, create and analyze various repeating patterns, evolving from simpler to more complex forms.