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- Minimalistic vision-based cognitive SLAMPublication . Saleiro, Mário; Rodrigues, J. M. F.; du Buf, J. M. H.The interest in cognitive robotics is still increasing, a major goal being to create a system which can adapt to dynamic environments and which can learn from its own experiences. We present a new cognitive SLAM architecture, but one which is minimalistic in terms of sensors and memory. It employs only one camera with pan and tilt control and three memories, without additional sensors nor any odometry. Short-term memory is an egocentric map which holds information at close range at the actual robot position. Long-term memory is used for mapping the environment and registration of encountered objects. Object memory holds features of learned objects which are used as navigation landmarks and task targets. Saliency maps are used to sequentially focus important areas for object and obstacle detection, but also for selecting directions of movements. Reinforcement learning is used to consolidate or enfeeble environmental information in long-term memory. The system is able to achieve complex tasks by executing sequences of visuomotor actions, decisions being taken by goal-detection and goal-completion tasks. Experimental results show that the system is capable of executing tasks like localizing specific objects while building a map, after which it manages to return to the start position even when new obstacles have appeared.
- Dietary nitrogen and fish welfarePublication . Conceição, L. E. C.; Aragão, C.; Dias, J.; Costas, B.; Terova, G.; Martins, C.; Tort, L.Little research has been done in optimizing the nitrogenous fraction of the fish diets in order to minimize welfare problems. The purpose of this review is to give an overview on how amino acid (AA) metabolism may be affected when fish are under stress and the possible effects on fish welfare when sub-optimal dietary nitrogen formulations are used to feed fish. In addition, it intends to evaluate the current possibilities, and future prospects, of using improved dietary nitrogen formulations to help fish coping with predictable stressful periods. Both metabolomic and genomic evidence show that stressful husbandry conditions affect AA metabolism in fish and may bring an increase in the requirement of indispensable AA. Supplementation in arginine and leucine, but also eventually in lysine, methionine, threonine and glutamine, may have an important role in enhancing the innate immune system. Tryptophan, as precursor for serotonin, modulates aggressive behaviour and feed intake in fish. Bioactive peptides may bring important advances in immunocompetence, disease control and other aspects of welfare of cultured fish. Fishmeal replacement may reduce immune competence, and the full nutritional potential of plant-protein ingredients is attained only after the removal or inactivation of some antinutritional factors. This review shows that AA metabolism is affected when fish are under stress, and this together with sub-optimal dietary nitrogen formulations may affect fish welfare. Furthermore, improved dietary nitrogen formulations may help fish coping with predictable stressful events.
- Conserved domains and evolution of secreted phospholipases A2Publication . Nevalainen, Timo J.; Cardoso, João CR; Riikonen, Pentti T.Secreted phospholipases A2 (sPLA2s) are lipolytic enzymes present in organisms ranging from prokaryotes to eukaryotes but their origin and emergence are poorly understood. We identified and compared the conserved domains of 333 sPLA2s and proposed a model for their evolution. The conserved domains were grouped into seven categories according to the in silico annotated conserved domain collections of cd00618: PLA2_like and pfam00068: Phospholip_A2_1. PLA2s containing the conserved domain cd04706 (plant-specific PLA2) are present in bacteria and plants. Metazoan PLA2s of the group (G) I/II/V/X PLA2 collection exclusively contain the conserved domain cd00125. GIII PLA2s of both vertebrates and invertebrates contain the conserved domain cd04704 (bee venom-like PLA2), and mammalian GIII PLA2s also contain the conserved domain cd04705 (similar to human GIII PLA2). The sPLA2s of bacteria, fungi and marine invertebrates contain the conserved domain pfam09056 (prokaryotic PLA2) that is the only conserved domain identified in fungal sPLA2s. Pfam06951 (GXII PLA2) is present in bacteria and is widely distributed in eukaryotes. All conserved domains were present across mammalian sPLA2s, with the exception of cd04706 and pfam09056. Notably, no sPLA2s were found in Archaea. Phylogenetic analysis of sPLA2 conserved domains reveals that two main clades, the cd- and the pfam-collection, exist, and that they have evolved via gene-duplication and gene-deletion events. These observations are consistent with the hypothesis that sPLA2s in eukaryotes shared common origins with two types of bacterial sPLA2s, and their persistence during evolution may be related to their role in phospholipid metabolism, which is fundamental for survival.
- Uma experiência de ensino com alunos do 9.º ano para promover o desenvolvimento do pensamento algébricoPublication . Nobre, Sandra; Amado, Nélia; Ponte, João Pedro daAs orientações curriculares atuais enfatizam que o ensino da Matemática deve decorrer de forma coere nte, incidir numa Matemática relevante e ser bem articulado nos diferentes anos de escolaridade. Para a Álgebra, um tema matemático onde a maioria dos alunos demonstra bastantes dificuldades de aprendizagem, o actual programa propõe um alargamento do seu e studo aos três ciclos de ensino, de forma articulada. É logo a partir dos primeiros anos que deve ser feito um trabalho de suporte para os ciclos seguintes. O 9.º ano de escolaridade antecede a transição do ensino básico para o secundário. Os alunos que p retendem prosseguir estudos necessitam de um conhecimento mais profundo de Álgebra, mas a compreensão de conceitos algébricos que requer maior abstracção torna -‐ se difícil para a maioria. Muitos alunos não desenvolvem uma compreensão adequada do simbolismo algébrico e revelam dificuldade no recurso a este tipo de representação em diversos contextos. Frequentemente, os alunos ao usarem métodos formais algébricos, na resolução de equações, operarem com os símbolos de uma forma mecânica, sem compreenderem o sig nificado das operações que realizam. Estas e outras dificuldades na aprendizagem da Álgebra contribuem para aumentar o desinteresse pela disciplina e diminuir a taxa de sucesso escolar. O desenvolvimento do pensamento algébrico é uma das grandes finalidade s no ensino da Matemática (Ponte et al., 2007). O Programa de Matemática do Ensino Básico apresenta como propósito principal do ensino da Álgebra: Desenvolver nos alunos a linguagem e o pensamento algébricos, bem como a capacidade de interpretar, represent ar e resolver problemas usando procedimentos algébricos e de utilizar estes conhecimentos e capacidade exploração e modelação de situações em contextos diversos. (Ponte et al., 2007, p. 55) A resolução de problemas, recomendada neste programa, é uma ac tividade que favorece a realização de experiências informais pelos alunos antes da manipulação algébrica formal. A folha de cálculo é vista como um excelente meio para estabelecer relações entre a linguagem algébrica e os métodos gráficos na realização de tarefas e na resolução de problemas. Neste artigo, descrevemos parte de uma experiência de ensino realizada em tópicos de Álgebra, numa turma do 9.º ano, onde é abordado o estudo dos sistemas de duas equações do 1.º grau a duas incógnitas. Pretendemos anal isar de que modo esta experiência promoveu o desenvolvimento do pensamento algébrico dos alunos neste tópico, em particular, na aprendizagem do método de substituição da resolução de sistemas.
- ElderViews. O Outro Lado da Relação de Cuidar: o Olhar do Idoso. Relatório de Revisão da LiteraturaPublication . São José, José; Barros, Rosanna; Samitca, Sanda; Teixeira, Ana RitaNa revisão da literatura que se segue pretendemos dar resposta à seguinte questão: o que é que se sabe, em termos científicos, sobre as perspetivas das pessoas idosas relativamente aos relacionamentos de cuidar em que estão inseridos? Far-se-á também uma caracterização da produção científica sobre esta problemática em termos das suas orientações teóricas e metodológicas, e ainda uma apreciação crítica da investigação revista, salientando-se os seus principais aspetos positivos e as suas principais fragilidades.
- Microbial quality and yeast population dynamics in cracked green table olives' fermentationsPublication . Alves, Maria; Gonçalves, Teresa; Quintas, CéliaCracked green table olives, from the Manzanilla variety, are a fermented food produced and consumed in Portugal. The objective of the present work was to study the microbiological characteristics and yeast population evolution during the fermentation of cracked green olives. The predominant microorganisms were yeasts while lactic acid bacteria were not detected and a clear decrease of the mould population was observed. At the end of the fermentations, no viable counts of Enterobacteriaceae were found. Yeast isolates were identified by the 5.8S rRNA-ITS region restriction analysis and by sequencing the D1/D2 region of the 26S rRNA gene. During the initial phases of the fermentations a great diversity of yeasts was observed. However, as the processes evolved the biodiversity decreased with the fermentative yeasts Citeromyces matritensis, Zygotorulaspora mrakii and Saccharomyces cerevisiae becoming the dominant species. The presence of these fermentative yeasts at the end of the production process is associated to a risk of spoilage. The results obtained represent a first attempt towards the comprehension of the microbiota of this type of “Natural olives” that constitute an important component of the Mediterranean diet.
- Evolution of outpatient antibiotic use in mainland Portugal 2000-2009Publication . Ramalhinho, Isabel; Ribeirinho, Mafalda; Vieira, Isaura; Cabrita, JoseIntroduction: In the latest years, the increasing resistance to antibiotics has become a serious public health issue. The resistance to antimicrobial agents is multifactorial although several studies have shown that the large use of antibiotics for therapeutical and prophylactic purposes, and particularly their misuse, is one factor that contributes most to this problem. Aim: To assess the evolution of antibiotic consumption in Portugal, Health Regions and Districts of Portugal, from 2000 to 2009. Material and Methods: Descriptive observational study using as source of information a database of outpatient antibiotic prescription provided by Infarmed, National Authority of Medicines and Health Products. Antibiotic consumption is estimated up from medical prescription, and expressed in DDD/1000 inhabitants/day (DHD). Results: From 2000 to 2009 antibiotic total consumption varied between 24,12 DHD and 22,03 DHD, which means a decrease by 8,65%. The use of tetracyclines (J01A), cephalosporins (J01D), sulphonamides (J01E), quinolones (J01M) and other antibacterials (J01B, J01G and J01X) decreased during the aforesaid time period. By contrast, there was an increase in the use of the combination penicilin and beta-lactamases inhibitor, and macrolides (J01F). Between 2000 and 2009 there was a significant decrease in the use of outpatient cephalosporins ( - 43,50%). Most notable is the large reduction of the use of cephalosporins between 2000 and 2009 (-43.50%) and also the decrease in the consumption of quinolones (-15.31%). Conclusion: Although there has been a decrease in the use of antibiotics in Portugal, their consumption is still high. The current study provides information that may be useful to regional Health Authorities in order to develop educational activities, for the population or health professionals, which can promote the rational use of antibiotics.
- What artificial grammar learning reveals about the neurobiology of syntaxPublication . Karl Magnus Petersson; Folia, Vasiliki; Hagoort, PeterIn this paper we examine the neurobiological correlates of syntax, the processing of structured sequences, by comparing FMRI results on artificial and natural language syntax. We discuss these and similar findings in the context of formal language and computability theory. We used a simple right-linear unification grammar in an implicit artificial grammar learning paradigm in 32 healthy Dutch university students (natural language FMRI data were already acquired for these participants). We predicted that artificial syntax processing would engage the left inferior frontal region (BA 44/45) and that this activation would overlap with syntax-related variability observed in the natural language experiment. The main findings of this study show that the left inferior frontal region centered on BA 44/45 is active during artificial syntax processing of well-formed (grammatical) sequence independent of local subsequence familiarity. The same region is engaged to a greater extent when a syntactic violation is present and structural unification becomes difficult or impossible. The effects related to artificial syntax in the left inferior frontal region (BA 44/45) were essentially identical when we masked these with activity related to natural syntax in the same subjects. Finally, the medial temporal lobe was deactivated during this operation, consistent with the view that implicit processing does not rely on declarative memory mechanisms that engage the medial temporal lobe. In the context of recent FMRI findings, we raise the question whether Broca's region (or subregions) is specifically related to syntactic movement operations or the processing of hierarchically nested non-adjacent dependencies in the discussion section. We conclude that this is not the case. Instead, we argue that the left inferior frontal region is a generic on-line sequence processor that unifies information from various sources in an incremental and recursive manner, independent of whether there are any processing requirements related to syntactic movement or hierarchically nested structures. In addition, we argue that the Chomsky hierarchy is not directly relevant for neurobiological systems. (C) 2010 Elsevier Inc. All rights reserved.
- Visual navigation for the blind: path and obstacle detectionPublication . José, João; Rodrigues, J. M. F.; du Buf, J. M. H.We present a real-time vision system to assist blind and visually impaired persons. This system complements the white cane, and it can be used both indoor and outdoor. It detects borders of paths and corridors, obstacles within the borders, and it provides guidance for centering and obstacle avoidance. Typical obstacles are backpacks, trash cans, trees, light poles, holes, branches, stones and other objects at a distance of 2 to 5 meters from the camera position. Walkable paths are detected by edges and an adapted Hough transform. Obstacles are detected by a combination of three algorithms: zero crossings of derivatives, histograms of binary edges, and Laws’ texture masks.
- Contributo da diretiva-quadro da água 2000/60/CE para a melhoria do controlo de qualidade da água de consumo humanoPublication . Pimentel, Cristina; Esteves, Eduardo; Moreira da Silva, ManuelaNo sentido de se analisar a evolução da qualidade da água para consumo humano imposta pelas orientações nacionais e comunitárias, em vigor nos últimos anos, procedeu-se a um estudo do desempenho dos laboratórios que realizam o seu controlo analítico. Para tal, recorreu-se à análise dos resultados de parâmetros físico-químicos dos ensaios interlaboratoriais fornecidos pela Associação Portuguesa de Laboratórios Acreditados (RELACRE), entre Maio de 2001 e Novembro de 2009, e avaliou-se a evolução temporal dos desempenhos dos laboratórios participantes, tendo por base os valores de Z-score em função da concentração do analito e o Erro normalizado aplicado à estimativa das incertezas. O Laboratório de Engenharia Sanitária da Universidade do Algarve (LES/UALG), primeiro laboratório de ensaios de águas acreditado nesta região, foi analisado como um caso de estudo. Os resultados obtidos indicam que a implementação da Diretiva-Quadro e de todas as outras orientações dela decorrentes, influenciou positivamente o desempenho dos laboratórios relativamente a nitratos, nitritos, amónia, alumínio, ferro, manganês e pH. Relativamente à avaliação da estimativa das incertezas através do Erro normalizado, também se verificou que estas melhoraram significativamente no período estudado. Para oxidabilidade, cor e turvação essa influência é menos evidente. No caso do Laboratório de Engenharia Sanitária da UALG, e no que diz respeito aos parâmetros dentro do âmbito da sua acreditação, verificou-se uma melhoria clara do seu desempenho durante o período estudado.