Browsing by Issue Date, starting with "1997"
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- O mito da Terra-Mãe-Deusa em The Bridge, de Hart CranePublication . Mancelos, João deNeste artigo, demonstro como o poeta modernista Hart Crane (1899-1932), na sua obra mais célebre, The Bridge (1932), apresenta diversas mulheres, associando-as ao ancestral mito da terra-mãe-deusa. Na secção “Powhatan’s Daughter”, o texto “The Harbor Dawn” transmite a concomitância terra-mulher, uma vez que a América é identificada com a princesa ameríndia Pocahontas. Posteriormente, “Indiana” refere as ligações entre mãe e filho, e entre duas mães de raças e civilizações diferentes. Em seguida, a trilogia simbólica “Three Songs” expõe a mulher como um ente de três rostos: mãe, prostituta, deusa. “Quaker Hill” encerra com o elogio de duas figuras exemplares da história cultural norte-americana: Emily Dickinson e Isadora Duncan. Para escorar o estudo, recorro à minha opinião, a especialistas na obra de Hart Crane, com destaque para Paul Giles, Vincent Quinn e Jack Wolf, e a diversos mitólogos.
- A method for particle location and field interpolation on complex, three-dimensional computational meshesPublication . Oliveira, Paulo J.; Gosman, A. D.; Issa, R. I.A method for locating particles within arbitrary three-dimensional computational meshes is described. It is based on an iterative procedure which uses transformed coordinates defined by iso-parametric functions. The method also enables one to interpolate field values from the mesh nodes to the particle position. Example applications demonstrate how effective the method is. For very distorted computational cells special practices have to be introduced in order to keep the number of iterations to a minimum.
- Escribir en una lengua que escuchamos robadaPublication . Vázquez Diéguez, Ignacio; Labraña Barrero, SabelaDesde que a finales de la Edad Media comenzó en Galicia la sustitución progresiva de la lengua propia por la de Castilla, la población gallega fue víctima de un conflicto lingüístico que no ha conseguido, hasta el momento, resolver satisfactoriamente. [...]
- Application of the Pitzer theory to the evaluation of pH of the phthalate standard solutionPublication . Mendonça, António; Ferra, Maria I.The pH value of the potassium hydrogen phthalate 0.05 mol.kg-1 has been detemined, using the Bates-Guggenheim convention and lhe Pitzer model for the calculation of the chloride íon activity coefficient. A comparison has been made between lhe two approaches.
- Judaísmo tardio e Helenismo. AproximaçõesPublication . Rosa, José Maria SilvaEste artigo procura analisar alguns temas da obra de Fílon de Alexandria «De Migratione Abrahami» de modo a encontrar nela relações entre a exegese alegórica que o autor faz de passagens bíblicas (no caso a Migração de Abraão), relacionando essas passagens com temas próprios da Filosofia Platónica (saída da caverna, contemplação das ideias, etc.) e suas reapropriações helenísticas.
- cGMP-stimulated cyclic nucleotide phosphodiesterase regulates the basal calcium current in human atrial myocytesPublication . Verde, Ignacio; Rivet-Bastide, Michèle; Vandecasteele, Grégoire; Hatem, Stéphane; Bénardeau, Agnès; Mercadier, Jean-Jacques; Fischmeister, RodolpheEHNA (Erythro-9-[2-hydroxy-3-nonyl]adenine) is a wellknown inhibitor of adenosine deaminase. Recently, EHNA was shown to block the activity of purified soluble cGMPstimulated phosphodiesterase (PDE2) from frog, human, and porcine heart with an apparent Ki value of approximately 1 microM and with negligible effects on Ca2+/calmodulin PDE (PDE1), cGMP-inhibited PDE (PDE3), and low Km cAMP-specific PDE (PDE4) (Méry, P.F., C. Pavoine, F. Pecker, and R. Fischmeister. 1995. Mol. Pharmacol. 48:121-130; Podzuweit, T., P. Nennstiel, and A. Muller. 1995. Cell. Signalling. 7:733- 738). To investigate the role of PDE2 in the regulation of cardiac L-type Ca2+ current (ICa), we have examined the effect of EHNA on ICa in freshly isolated human atrial myocytes. Extracellular application of 0.1-10 microM EHNA induced an increase in the amplitude of basal ICa ( approximately 80% at 1 microM) without modification of the current-voltage or inactivation curves. The maximal stimulatory effect of EHNA on ICa was comparable in amplitude with the maximal effect of isoprenaline (1 microM), and the two effects were not additive. The effect of EHNA was not a result of adenosine deaminase inhibition, since 2'-deoxycoformycin (1-30 microM), another adenosine deaminase inhibitor with no effect on PDE2, or adenosine (1-10 microM) did not increase ICa. In the absence of intracellular GTP, the substrate of guanylyl cyclase, EHNA did not increase ICa. However, under similar conditions, intracellular perfusion with 0.5 microM cGMP produced an 80% increase in ICa. As opposed to human cardiomyocytes, EHNA (1-10 microM) did not modify ICa in isolated rat ventricular and atrial myocytes. We conclude that basal ICa is controlled by PDE2 activity in human atrial myocytes. Both PDE2 and PDE3 may contribute to keep the cyclic nucleotides concentrations at minimum in the absence of adenylyl and/or guanylyl cyclase stimulation.
- Innovation, Technological Transfer and Competitiviness: A territorial approach.Publication . Couto, Alcino Pinto; Reigado, Felisberto MarquesThe aim of this paper is to discuss the innovation and the technological transfer in what concerns their impact on the competitiveness of the performance of lagging regions. The distinction between the concept of innovation and technological transfer seems to be relativised, since it is assumed that the conditions for the operationalisation of the process of technological endogeneisation require contextual conditions similar to the regions that export technology. Some conclusions about the role of some factors must be taken from studies carried out and from our empirical research, concerning Beira Interior, such as the industrial structure, the quality of entrepreneurial activity and networks and cooperation for innovation, which might appear as a struggle to the process of innovation and to the technological accumulation. We also stress some of the implications on the regional policy
- Um livro sobre livros: o cavalo a tinta-da-china, de Baptista-BastosPublication . Mancelos, João deRecensão ao romance O Cavalo a Tinta-da-China, de Baptista-Bastos, focando sobretudo a reflexão metapoética e a visão do salazarismo.
- Pressure drop coefficient of laminar newtonian flow in axisymmetric sudden expansionsPublication . Oliveira, Paulo J.; Pinho, FernandoLaminar flow of a Newtonian fluid in an axisymmetric pipe expansion has been studied numerically by means of the finite-volume approach. Predicted values of some of the overall flow characteristics, such as recirculation length, its strength, and centre location, were compared with available experimental data and correlations, and good agreement was found. The purpose of the work was to evaluate the pressure-loss coefficient Cl for a range of Reynolds numbers and to compare the results with existing simplified theory, which is based on a one-dimensional (1-D) overall balance of energy and momentum. Considerable differences were found, which lead us to formulate corrected theoretical equations in the scope of the 1-D approximation. These corrections were evaluated from the numerical results and accounted for three effects: (1) differing actual and fully developed wall friction; (2) distortion of velocity profiles from the parabolic shape at the sudden expansion section; and (3) nonuniformity of pressure at the expansion plane. Predicted values of the loss coefficient agreed to within 4% with the corrected theory and were found to be proportional to the inverse of the Reynolds number for Re ≤ 17.5 [with effect (3) above predominant and accounting for up to 85% of Cl] and approximately constant for Re > 17.5 [with effect (1) above predominant and accounting for 20% of Cl]. Finally, a correlation for calculating the local loss coefficient as a function of the Reynolds number for the 1:2.6 sudden expansion and fully developed conditions is proposed.
- Penetration Resistance Tests on High Strength ConcretePublication . Lopes, Sérgio Manuel Rodrigues; Nepomuceno, MiguelThe aim of the investigation described here is to verify the applicability of penetration resistance tests on high strength concrete as a way of estimating its compressive strength “in situ”. A relationship between compressive strength of a given concrete and its resistance to penetration by a steel probe fired into the concrete surface is presented to a compressive strength range varying from 50 MPa to 90 MPa using an alternative firing apparatus to the standard apparatus Windsor Probe Test System.