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- Ozone deposition modelling in a portuguese coastal zonePublication . Valinhas, Maria José; Borrego, Carlos; Barros, Nelson; Carvalho, Ana CristinaThe deposition of pollutants from the atmosphere to ecosystems is the cause of some present environmental problems: acidification, eutrophication and, indirectly, ground level ozone. Related with these issues is the critical loads/levels concept, widely accepted in Europe as basis for pollution control strategies. The knowledge of atmospheric pollutants deposition on ecosystems is needed to setup this methodology. This paper presents the parameterisation done in the deposition module of the system of models MAR IV which is adequate to simulate the transport, dispersion and removal of pollutants, including ozone production for mesoscale application. The ozone surface resistance (Rc) pararneterisation was applied to Lisbon region and the modelk performance was assessed with ozone deposition experimental data observed in the study area during the fieldwork LisbEx 97. The influence of parameterisation became evident with the good fit between modelled results and measured data. Based on an empirical method described by the Stockholm Environmental Institute report a Critical Load map, for non-forested areas, was calculated for Pomgal. The methodology is based on the kind of soil and its buffer capacity to acid compounds, The results show that around 70°/0of the country is in sensitive areas reinforcing the need for the application of this concept.
- Influence of traffic emissions estimation variability on urban air quality modellingPublication . Borrego, Carlos; Tchepel, Oxana; Monteiro, Alexandra; Barros, Nelson; Miranda, Ana IsabelThe main objective of this work is to analyse how uncertainties in emission data of nitrogen oxides (NOx) and volatile organic compounds (VOC), originated from road traffic, influence the model prediction of ozone (O3) concentration fields. Different methods to estimate emissions were applied and results were compared in order to obtain their variability. Based on these data, different emission scenarios were compiled for each pollutant considering the minimum and the maximum values of the estimated emission range. These scenarios were used as input to the MARIV mesoscale modelling system. Simulations have been performed for a summer day in the Northern Region of Portugal. The different approaches to estimate NOx and VOC traffic emissions show a significant variability of absolute values and of their spatial distribution. Comparison of modelling results obtained from the two scenarios presents a dissimilarity of 37% for ozone concentration fields as a response of the system to a variation in the input emission data of 63% for NOx and 59% for VOC. Far beyond all difficulties and approximations, the developed methodology to build up an emission data base shows to be consistent and an useful tool in order to turn applicable an air quality model. Nevertheless, the sensitivity of the model to input data should be considered when it is used as a decision support tool.
- A idade dos homens do poder: novos e velhos na burocracia de D. Afonso V (1439-1460)Publication . Freitas, Judite A. Gonçalves de; yes
- Cu2+-induced isoproterenol oxidation into isoprenochrome in adult rat calcium-tolerant cardiomyocytesPublication . Remião, Fernando; Carvalho, Márcia; Carmo, Helena; Carvalho, Félix; Bastos, Maria L.Sustained high levels of circulating catecholamines may induce cardiotoxicity. There is increasing evidence that this could result from catecholamine oxidation into aminochromes, which is catalyzed by transition metals. In fact, it has already been shown that copper-induced oxidation of the beta-agonist isoproterenol decreases the viability of isolated cardiomyocytes. Thus, the aim of this work was to contribute for the clarification of the mechanisms underlying the toxic effects of isoproterenol, Cu2+ and their concomitant effect in isolated rat cardiomyocytes. Freshly isolated calcium-tolerant cardiomyocytes from adult rat were incubated with 1 mM isoproterenol, 20 microM Cu2+ or with both during 4 h. Isoproterenol and its aminochrome (isoprenochrome), and reduced and oxidized glutathione were measured at each hour in the incubation medium and in the cells. The intracellular activities of the selenium-dependent glutathione peroxidase, glutathione reductase, and glutathione-S-transferase were determined after 4 h of incubation. Isoprenochrome was found in both cells and incubation medium in samples incubated with isoproterenol alone. However, in the isoproterenol plus Cu2+ samples, a greater depletion of isoproterenol accompanied by a proportional increase of isoprenochrome was observed. This higher ISO oxidation resulted in the depletion of intracellular glutathione and in the release of oxidized glutathione to the incubation medium. The content of total glutathione (intra- and extracellular) and the intracellular activity of the selenium-dependent glutathione peroxidase, glutathione reductase, and glutathione-S-transferase were also decreased in the isoproterenol plus Cu2+ samples. These results seem to indicate that the oxidative stress resulting from catecholamine/transition metal association may contribute to catecholamine cardiotoxicity.
- Aspectos físicos das "Aparições Marianas" de Fátima, 1917 - sistematização e modelização preliminaresPublication . Fernandes, JoaquimO presente texto pretende sistematizar um conjunto de reacções e sensações físicas relatadas, por diversas testemunhas, à época dos clássicos eventos religiosos da Cova de Iria, em 1917. Propõe-se a possibilidade de ter ocorrido em Fátima, no decurso das experiências das "aparições", uma série de fenómenos, ligados por nexos causais e por uma economia de hipóteses, plausíveis e identificáveis hoje pelo acumular dos conhecimentos científicos e pelo esforço de reflexão de diferentes investigadores. Assume-se que os depoimentos não poderiam antecipar efeitos similares, posteriormente enunciados em diferentes contextos culturais e síndromes fenomenológicas excepcionais. Projectam-se alguns modelos teóricos recolhidas da literatura e de informações directamente comunicadas ao autor. Enumeram-se experiências laboratoriais recentes e modelos oriundos de áreas convergentes, interdisciplinares, susceptíveis de abrir novas perspectivas sobre eventuais processos físicos, equivalentes aos registados no decurso das manifestações aparicionais. Destacam-se, em especial, as implicações para a formulação de um modelo de comunicação não-verbal, extensiva a experiências de "contacto" laico e religioso intemporal e transcultural e refere-se a emergência de uma nova área transdisciplinar: a neuroteologia ou neurobiologia da religião.
- New developments in presentiment research or the nature of timePublication . Bierman, Dick J.Human physiology changes in predictable ways in anticipation of and after exposure to emotional visual stimuli. In a series of experiments reported by Radin (1997), it was found that even when stimuli were adequately randomized, so that the upcoming stimuli could not be inferred, that anticipatory responses (as measured by changes in skin conductance) before exposure to emotional pictures were significantly larger than before exposure to calm pictures. In three subsequent expreriments, the first and third close replications and the second a conceptual replication of Radin s studies, Bierman confirmed this so called "presentiment" or pre-feeling effect. Bierman sub-sequently decided to see whether these anomalies observed in physiological baseline measurements could also be found in data from studies published previously in the main stream literature. Two datasets were found and reanalyzed. The first dataset as from a study on the speed with which fear arises in animal phobic participants vs. controls by the German group of Hamm. The second study was concerned with the difference in anticipatory responses prior to choosing cards from risky vs. non-risky decks of cards in a gambling task by the US group of Damasio. The combined result showed a significant anomalous difference similar to the effects found in the original studies by Radin and Bierman. A new development in presentiment research is the measurement of brain images rather than skin conductance preceding the presentation of randomized neutral and emotional stimuli. Preliminary results suggest that the anomaly can be located in the brain. This would allow for more detailed inspection of differences between different types of emotional stimuli like violent and erotic.
- Panspermia in perspectivePublication . Wickramasinghe, N. C.Panspermia, an ancient theory implying the dispersal of life throughout the universe, was revived in its modern form by Fred Hoyle and the present author in a series of publications over the period 1977 to 2001. Although unpopular at first, it is now slowly gaining support and is coming to be discussed as a serious scientific possibility among theories of the origin of life. A summary will be given of the modern scientific case of panspermia, indicating that astronomical, geological and biological evidence is converging towards its support.
- Inteligência artificial, texto automático e criação de sentidoPublication . Barbosa, PedroOs sonhos da Inteligência Artificial na actual Literatura Gerada por Computador e na Ciberarte. Texto automático, lógica maquínica e algoritmos linguísticos na criação de sentido(s). Problemas de referência: jogos de linguagem e construção do real. The automatic generation of the text and generative literature as folowers of the proposals of Artificial Intelligence (AI); human dimesion and machinic dimension in the treatment of language; the machine as an extender of complexity in the infinite combinatory of signs; field of reading and horizon of possibilities; language games and construction of meaning. The case of the textual sinthesizer Sintext-W: degrees of interactivitye and «(w)reading».
- Editorial [de] Cons-Ciências, nº 1Publication . Fernandes, Joaquim; Santos, Nelson Lima
- Medicina biológica: Sistema "Prognos"Publication . Lozano Calvo, Jesus