Enseñanza de ELE a través de un sistema informático de análisis textual disponible en Internet

La creciente importancia de los corpus de textos digitalizados para la enseñanza de lenguas ha sido puesta de manifiesto por distintos autores a lo largo de los últimos años. Tribble y Jones (1990), Flowerdew (1993), Botley et al. (1996) y Sánchez (2000), entre otros, han subrayado la utilidad didáctica de los corpus textuales y de los sistemas informáticos que permiten consultarlos

Liver replacement after massive hepatic trauma

Two patients sustained massive hepatic injuries from blunt trauma in motor vehicle accidents. At the time of operation, nonreconstructable injuries to the porta hepatis were found in addition to destruction of the right lobe. Life-threatening hemorrhage was controlled, but both patients were left with nonfunctional or inadequate hepatic remnants. Liver transplantation was performed. Both patients recovered after liver replacement. One died 7 weeks later of cytomegalovirus infection. The other recipient is well 16 months later. Liver transplantation is a reasonable option in patients with lethal hepatic injuries or unreconstructable injuries to the porta hepatis. © Williams & Wilkins 1987. All Rights Reserved

An approach to phenotypic analysis and environmental variability. The examples of the genera Dianthus L. and Lotus L. in the north of Portugal

The analysis of the correlation between phenotypic plasticity and environmental variability has been very useful to describe the morphologic responses of individuals to environmental factors affecting them (in the present contribution the altitudinal variation), from a genecological perpective. However, the literature shows that the studies in this area have had a monospecific or monogeneric use. As a consequence, intergeneric comparative descriptions have not been possible. In the present work we propose an analytical method to compare the morphological expressivity of individuals included in the genera Dianthus and Lotus from the north of Portugal by means of a contingency matrix. This matrix was elaborated on the basis of amplitude parameters, in order to describe the variability present in the basic matrix of each genus studied. The results pointed out the existence of opposite phenotypic behaviours dependent on the altitudinal variation, thus indicating the importance of the analysis between different groups of taxa as a reference for the comparison of their morphological expressivities

On the relativistic origin of the kink effect in the chain of Pb isotopes

We investigate the origin of the kink effect (KE) in the relativistic mean field theory by transforming the single-particle Dirac equation into a Schrodinger-like equation. It is found that relativistic self-consistent effects as well as contributions from the rho meson determine the actual structure of the KE. However, the spin-orbit force generated by the rho meson has no significant influence on the KE.Comment: 11 pages, RevTeX, 3 postscript figs., Phys. Lett.

Competition of ferromagnetic and antiferromagnetic spin ordering in nuclear matter

In the framework of a Fermi liquid theory it is considered the possibility of ferromagnetic and antiferromagnetic phase transitions in symmetric nuclear matter with Skyrme effective interaction. The zero temperature dependence of ferromagnetic and antiferromagnetic spin polarization parameters as functions of density is found for SkM$^*$, SGII effective forces. It is shown that in the density domain, where both type of solutions of self--consistent equations exist, ferromagnetic spin state is more preferable than antiferromagnetic one.Comment: 9p., 3 figure

Instabilities of infinite matter with effective Skyrme-type interactions

The stability of the equation of state predicted by Skyrme-type interactions is examined. We consider simultaneously symmetric nuclear matter and pure neutron matter. The stability is defined by the inequalities that the Landau parameters must satisfy simultaneously. A systematic study is carried out to define interaction parameter domains where the inequalities are fulfilled. It is found that there is always a critical density $\rho_{cr}$ beyond which the system becomes unstable. The results indicate in which parameter regions one can find effective forces to describe correctly finite nuclei and give at the same time a stable equation of state up to densities of 3-4 times the saturation density of symmetric nuclear matter.Comment: 20 pages, 5 figures, submitted to Phys.Rev.

ONTOGENERATION: Reusing Domain and Linguistic Ontologies for Spanish Text Generation

A significant problem facing the reuse of ontologies is to make their content more widely accessible to any potential user. Wording all the information represented in an ontology is the best way to ease the retrieval and understanding of its contents. This article proposes a general approach to reuse domain and linguistic ontologies with natural language generation technology, describing a practical system for the generation of Spanish texts in the domain of chemical substances. For this purpose the following steps have been taken: (a) an ontology in the chemicals domain developed under the METHONTOLOGY framework and the Ontology Design Environment (ODE) has been taken as knowledge source; (b) the linguistic ontology GUM (Generalized Upper Model) used in other languages has been extended and modified for Spanish; (c) a Spanish grammar has been built following the systemic-functional model by using the KPML (Komet-Penman Multilingual) environment. As result, the final system named Ontogeneration permits the user to consult and retrieve all the information of the ontology in Spanish

Spin symmetry in Dirac negative energy spectrum in density-dependent relativistic Hartree-Fock theory

The spin symmetry in the Dirac negative energy spectrum and its origin are investigated for the first time within the density-dependent relativistic Hartree-Fock (DDRHF) theory. Taking the nucleus $^{16}$O as an example, the spin symmetry in the negative energy spectrum is found to be a good approximation and the dominant components of the Dirac wave functions for the spin doublets are nearly identical. In comparison with the relativistic Hartree approximation where the origin of spin symmetry lies in the equality of the scalar and vector potentials, in DDRHF the cancellation between the Hartree and Fock terms is responsible for the better spin symmetry properties and determines the subtle spin-orbit splitting. These conclusions hold even in the case when significant deviations from the G-parity values of the meson-antinucleon couplings occur.Comment: 13 pages, 7 figures, 1 table, accepted by Eur. Phys. J.