Era uma vez... no ensino da biologia e da geologia

Dissertação de mest., Biologia e Geologia, Faculdade de Ciências do Mar e do Ambiente, Univ. do Algarve, 2007

Aims of education and well-being as absence of disorder

This thesis offers an original account of what personal well-being can be. Any account of education, it is believed, has to do with and aims at personal well-being. I approach this view on well-being not in a positive but in a negative way. I put forward some items that in certain circumstances can be taken by and called sources or forms of disorder. In the absence of such forms or sources of disorder, I assume that a certain order, prudential or moral, takes place and that constitutes the well-being of the person. The concept of ‘absence of disorder’ is introduced and argued as an educationally appropriate view of personal well-being which is the central educational aim. Therefore, ‘absence of disorder’ is positioned as the central aim of education. This concept is illuminated, for practical reasoning, by a list of seven possible forms of disorder: Comparison, Corruption, Dependency, Division, Fear, Self-disintegration and Violence. As a view of personal well-being, ‘absence of disorder’ is initially rooted in informed desire satisfaction, via the introduction of the concept of entropy. Prudentially, the agent’s informed desire is satisfied by living a life with low build up of entropy or disorder. But, in a second move such a base is also provided by the Levinasinian concept of ‘disinterest’ as a root for ‘what is to be a human’. Such ‘disinterest’ is related to the concepts of love and of ‘action for its own sake’. It is at this final approach that an attempt is made towards the approximation of the ethical and the prudential aspects of social practices. Even if only to some extent successful, the argument is directed to the following conclusion: an education aiming at ‘absence of disorder’ may promote prudential well-being and give us some confidence in simultaneously favouring moral education.

Operárias no caminho da emancipação social contra a exploração e o estado. O caso da Comissão de Trabalhadores da conserveira Júdice Fialho.

Este artigo reflete sobre os processos educativos populares, desenvolvidos em contexto de crise do estado e suportados por uma dinâmica de transformação social revolucionária. O contexto de análise empírica é focalizado numa empresa da indústria conserveira sedeada em Portimão. O contexto histórico reporta-se ao período revolucionário vivido em Portugal entre o 25 de abril de 1974 e as eleições para a Assembleia da República em abril de 1976. Constituindo um estudo de caso, válido ‘per si’, os procedimentos metodológicos assentaram no uso das técnicas da pesquisa documental e da entrevista profunda, privilegiando os atores que o vivenciaram e que, de forma interpretativa, testemunham a sua leitura atual dos processos e das aprendizagens alcançadas. Estes processos de educação, desenvolvidos pelos operários e trabalhadores neste período, denunciam a construção de uma aprendizagem coletiva, assente no reforço dos seus saberes da vida e do trabalho, almejando uma intervenção mais participativa nos mecanismos da governação e da gestão política. Para isso socorreram-se da organização de instrumentos de poder coletivo, inerentes à história do movimento operário, como as comissões de trabalhadores, com critérios de democraticidade de base, transparência e comunhão coletiva. Quase sempre, esta estrutura se confrontou direta e frontalmente com a administração patronal e, mais tarde, com os peritos de gestão governamental, durante a intervenção estatal na empresa. Este processo foi também vivido contra a visão controladora e corporativa do sindicato local conserveiro, controlado por burocracias sindicais, ou mesmo fugindo às tentativas de manipulação das organizações partidárias.

The importance of the pelagic larval phase of the wedge shell Donax trunculus (L.): implications for the management of the fishery

The wedge shell, Donax trunculus, inhabits high energy environment of exposed sandy beaches from the Atlantic coast of France to Senegal. Like all Donacidae, it is relative small, flat-shaped with elongated solid shells. It is a highly demanded and valuable species mainly in Algarve, with the dredge fleet increasing the pressure on species stocks. In 1986 the Portuguese Institute for the Ocean and Atmosphere (IPMA) initiated a bivalve survey program to evaluate the stock status of species with economical valuable but always on the adult population. Since then, several managing measures were implemented to guarantee bivalves’ sustainable exploitation. Despite the available information on the abundance and distribution of the wedge shell along the Algarve coast, no information on the larval planktonic phase is available. To fill in this gap, the present study aimed at obtaining, for the first time information on the broodstock condition and on the pelagic phase of the wedge shell in the Algarve coast.

Electrical characterization of metal-oxide-polymer devices for non-volatile memory applications

The objective of this thesis is to study the properties of resistive switching effect based on bistable resistive memory which is fabricated in the form of Al2O3/polymer diodes and to contribute to the elucidation of resistive switching mechanisms. Resistive memories were characterized using a variety of electrical techniques, including current-voltage measurements, small-signal impedance, and electrical noise based techniques. All the measurements were carried out over a large temperature range. Fast voltage ramps were used to elucidate the dynamic response of the memory to rapid varying electric fields. The temperature dependence of the current provided insight into the role of trapped charges in resistive switching. The analysis of fast current fluctuations using electric noise techniques contributed to the elucidation of the kinetics involved in filament formation/rupture, the filament size and correspondent current capabilities. The results reported in this thesis provide insight into a number of issues namely: (i) The fundamental limitations on the speed of operation of a bi-layer resistive memory are the time and voltage dependences of the switch-on mechanism. (ii) The results explain the wide spread in switching times reported in the literature and the apparently anomalous behaviour of the high conductance state namely the disappearance of the negative differential resistance region at high voltage scan rates which is commonly attributed to a “dead time” phenomenon which had remained elusive since it was first reported in the ‘60s. (iii) Assuming that the current is filamentary, Comsol simulations were performed and used to explain the observed dynamic properties of the current-voltage characteristics. Furthermore, the simulations suggest that filaments can interact with each other. (iv) The current-voltage characteristics have been studied as a function of temperature. The findings indicate that creation and annihilation of filaments is controlled by filling and neutralizing traps localized at the oxide/polymer interface. (v) Resistive switching was also studied in small-molecule OLEDs. It was shown that the degradation that leads to a loss of light output during operation is caused by the presence of a resistive switching layer. A diagnostic tool that predicts premature failure of OLEDs was devised and proposed. Resistive switching is a property of oxides. These layers can grow in a number of devices including, organic light emitting diodes (OLEDs), spin-valve transistors and photovoltaic devices fabricated in different types of material. Under strong electric fields the oxides can undergo dielectric breakdown and become resistive switching layers. Resistive switching strongly modifies the charge injection causing a number of deleterious effects and eventually device failure. In this respect the findings in this thesis are relevant to understand reliability issues in devices across a very broad field.