Browsing by Issue Date, starting with "2007-05"
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- Performance evaluation in Portuguese electricity distribution utilitiesPublication . Santos, Sérgio Pereira dos; Amado, Carla; Rosado, Joaquim; Rodrigues, Paulo M. M.; Santos, Sérgio Pereira dos; Ferreira, F. A. F.The Portuguese electricity system has undergone a major transformation in recent years due to its integration in the liberalised Iberian market. The group responsible for the electricity generation and distribution in Portugal (EDP) has been consistently focusing in service quality and efficiency. In the last 3 years, a stringent cost cutting and efficiency improvement program was implemented. This paper conducted a Data Envelopment Analysis (DEA) study to measure the relative efficiency of the 14 electricity distribution units belonging to EDP. A dynamic analysis using Malmquist Indices was also conducted in order to evaluate the changes in productivity from 2002 to 2005. Our results show that, on average, we can find evidence of 2% productivity gains in the Portuguese electricity distribution sector. Furthermore, we found evidence of significant discrimination among regional areas, suggesting that a benchmarking exercise based on the DEA results could be valuable for performance improvement in some regions.
- Les racistes c’est les autres. Les origines du mythe du «non-racisme» des PortugaisPublication . Marques, João Filipe"Existe na sociedade portuguesa « o preconceito de não ter preconceitos ». De onde vem, então, este mito tão resistente do « não racismo » dos portugueses ? Poderá ele desempenhar o papel de « hipocrisia criadora » imunizando os portugueses relativamente às formas mais virulentas de racismo relativamente às populações originadas pela imigração africana ? Foi na sequência dos ataques internacionais à situação colonial que, nos anos sessenta do Séculoxx, a doutrina lusotropicalista de Gilberto Freyre vai ser apropriada pelo regime de Salazar. Tornou-se necessário convencer o mundo e os portugueses da ausência de racismo na « essência » do ser português. O « não-racismo » tornou-se num mito fundador da expansão portuguesa no mundo. Mas procurando justificar uma situação inequivocamente racista - a dominação colonial - transformouse, de certa forma, numa « hipocrisia criadora » : acabou por contribuir para condicionar a realidade social e cultural contemporânea. Através de uma espécie de « efeito perverso », tendo querido justificar e prolongar a situação colonial, o Estado Novo inoculou nos portugueses uma espécie de vacina que tem impedido, até agora, as manifestações de « racismo diferencialista » e a passagem do racismo para o terreno do político."
- O impacto económico e orçamental dos investimentos nas redes ferroviárias efectuados pela REFERPublication . Pereira, Alfredo; Andraz, Jorge MiguelA relevância e a importância estratégica que o investimento em infra-estruturas de transporte tem assumido nas últimas décadas na estratégia de desenvolvimento do país, tem conduzido a um grande desenvolvimento da investigação sobre os seus reais efeitos sobre o desempenho económico. O presente trabalho encerra em si a preocupação de se conhecer, de forma objectiva e rigorosa, a realidade sobre o investimento na rede ferroviária, bem como de se avaliar os seus efeitos ao nível dos impactos na actividade económica do país e na evolução das receitas fiscais do Estado.
- Kinetic model of cadmium accumulation and elimination and metallothionein response in Ruditapes decussatusPublication . Serafim, Angela; Bebianno, Maria JoãoThe aim of the present study was to determine the response of metallothionein (MT) during Cd accumulation and elimination in different tissues of the estuarine bivalve Ruditapes decussatus exposed to two nominal Cd concentrations (4 and 40 microg/L) for 40 d, followed by a depuration period of 50 d. Cadmium was accumulated in all tissues of R. decussatus at both exposure concentrations, and the accumulation was tissue dependent. Use of the kinetic model showed that in the gills and remaining tissues, Cd was assimilated faster at the beginning of the exposure and decreased with time, possibly limited by the diffusion rate of this metal within the cell. In the digestive gland, however, the Cd was continuously accumulated. This could reflect that the Cd uptake rate is considerably higher than the loss rate and, therefore, that this tissue has a higher capacity to accumulate Cd compared to the other two tissues. Moreover, the application of this kinetic model in the different subcellular fractions showed that the bioconcentration factor was significantly higher in the low-molecular-weight fraction (where MT is found), suggesting that this fraction binds Cd faster, with a high uptake rate (K(u) = 32/d), and eliminates this metal more slowly (K(1) = 0.005/d). During the depuration phase, MT decreased simultaneously with Cd elimination in all tissues, although with a shorter half-life. In conclusion, the MT response prevented Cd in the tissues of R. decussatus from interfering in the normal clam metabolism; therefore, MT acts as a detoxification mechanism of Cd.
- Performance measurement in portuguese local governmentPublication . Santos, Sérgio Pereira dos; Vieira, Rui; Pina, PauloThe continuing reforms of local government systems worldwide, driven by the "New Public Management" movement, have called for innovative systems of measuring (and reporting) performance and have led to the renewal of interest in performance measurment. Despite this, the extent to which performance measurement has taken hold in a meaningful way and impacted the local government of several countries, including Portugal, is still an open question. The objective of this paper is to contribute to filling this void by setting a research agenda for the study of Performance measurement in Portuguese municipalities.
- Between looking and gesturing: Pierre Hébert's concept 'animation d'observation'Publication . Graça, Marina EstelaThe French Canadian filmmaker Pierre Hébert expression ‘animation d’observation’ (literally, observation animation) first appears within the context of the production of his film Etienne et Sara (1984) and is only employed there and during the implementation of the following film project: The Subway, Songs and Dances of the Inanimate world / Le Metro, Chants et Danses du Monde Inanimé (1985). At that time, Hébert's poetics go through what is perhaps their most important transformation. Etienne et Sara, started out being the last in a series of films whose project should have been resolved in a collation of multiple graphic and moving expressions, i.e. within the scope of what we commonly call the techniques of the animated film. However, following Pierre Hébert's meeting with the Belgian poet Serge Meurant, it became evident that it was more than just a film. In Confitures de Gagaku (1986), the following production to The Subway, Songs and Dances of the Inanimate world / Le Metro, Chants et Danses du Monde Inanimé, where for the first time he is animating in the presence of the spectators, in dialogue with the saxophonist Jean Derome, the film already appears clearly as a manifestation – albeit an autonomous one – of a project which is formed in a situation of open frontiers in the collision of languages, in a precise time and space. In it the author exhibits and lays claim to the origin of the film for the body, alive and feeling, of its maker, thereby questioning the ideological workings of the whole film making machinery and protocols. In this essay I will try to explain the author’s intention when he invented and then used such verbal device within the context of his work and, broadly, that of contemporary animation.
- Olfactory sensitivity to conspecific bile fluid and skin mucus in the European eel Anguilla anguilla (L.)Publication . Huertas, Mar; Hubbard, Peter; Canario, Adelino V. M.; Cerda, J.The present study assessed the olfactory potency of conspecific bile fluid and skin mucus in the European eel Anguilla anguilla by the electro-olfactogram. Immature males showed high olfactory sensitivity to conspecific bile, giving large amplitude responses in a concentrationdependent manner with estimated thresholds of detection of <1:107 (n = 6). Mucus also proved to contain highly potent odorants with thresholds of detection of c. 1:106 (n = 6). Crude solidphase extraction of bile fluid (C-18 and C-2/ENV+ cartridges) showed that the majority of olfactory activity in bile fluid was contained in the eluate of C-18 cartridges (n = 6). There were quantitative differences, however, between the sexes; female bile fluid had a higher proportion of activity in this fraction. Similar solid-phase extraction of mucus showed that it contains a higher proportion of odorants in the C-18 filtrate than bile fluid. Mucus from mature eels, however, had a higher proportion of olfactory activity in the eluate than immature fish (n = 6). Cross-adaptation experiments suggest that there are qualitative differences in the odorants contained in bile and mucus depending on both the sex and state of sexual maturation of the donor (n = 6). These results are consistent with a role for chemical communication in the reproduction of the European eel and suggest that both bile and mucus are potential sources of the odorants involved.
- Teorema de Rolle e a regra de DescartesPublication . Vaz, Dalila Maria Palma Afonso; Rodriguez, Maria Teresa Alzugaray; Rodriguez, Juan Sanchez CarlosFrom algebra we know that a polynomial of degree n with real coe±cients has at most n real zeros. But this result does not give any information about the number of positive zeros of such a polynomial. This question take us to Descarte's Rule of Signs, which give an upper bound for the number of positive zeros of a real polynomial. In this work we study Descarte's Rule of Signs following the work of P¶olya and SzegÄo in [8, Parte 5, cap.1]. We successively study the zeros and sign variations of a function, the sign changes of a sequence and present an algebraic proof of Descarte's Rule of Signs. We show some applications of Descartes's Rule of Signs and Rolle's Theorem to the resolution of some problems from algebra and analysis. Using Rolle's Theorem we prove analytically the Rule of Signs and use this method of proof to extend Descarte's Rule of Signs to di®erent systems of functions, ending with a necessary and su±cient condition for a system of functions to satisfy Descarte's Rule of Signs.
- Developmental expression of DAX1 in the European sea bass, Dicentrarchus labrax: lack of evidence for sexual dimorphism during sex differentiationPublication . Martins, Rute S. T.; Deloffre, Laurence A. M.; Mylonas, Constantinos C.; Power, Deborah; Canario, Adelino V. M.DAX1 (NR0B1), a member of the nuclear receptors super family, has been shown to be involved in the genetic sex determination and in gonadal differentiation in several vertebrate species. In the aquaculture fish European sea bass, Dicentrarchus labrax, and in the generality of fish species, the mechanisms of sex determination and differentiation have not been elucidated. The present study aimed at characterizing the European DAX1 gene and its developmental expression at the mRNA level.
- A PTH/PTHrP receptor antagonist blocks the hypercalcemic response to estradiol-17bPublication . Fuentes, J.; Guerreiro, P. M.; Modesto, Teresa; Rotllant, J.; Canario, Adelino V. M.; Power, DeborahEstradiol (E2) increases circulating calcium and phosphate levels in fish, thus acting as a hypercalcemic and hyperphosphatemic factor during periods of high calcium requirements, such as during vitellogenesis. Since parathyroid hormone (PTH)-related protein (PTHrP) has been shown to be calciotropic in fish, we hypothesized that the two hormones could be mediating the same process. Sea bream (Sparus auratus) juveniles receiving a single intraperitoneal injection of piscine PTHrP(1-34) showed an elevation in calcium plasma levels within 24 h. In contrast, injections of the PTH/PTHrP receptor antagonist PTHrP(7-34) decreased circulating levels of calcium in the same period. Intraperitoneal implants of estradiol-17 (E2; 10 g/g) evoked significant increases of circulating plasma levels of calcium and phosphorus and a sustained increases of circulating plasma levels of PTHrP. However, a combined treatment of E2 and PTHrP(7-34) evoked a markedly lower calcium response compared with E2 alone. We conclude that PTHrP or a related peptide that binds the PTH/PTHrP receptor mediates, at least in part, the hypercalcemic effect of E2 in calcium and phosphate balance in fish.