In this paper we exhibit a non-finitely based, finitely generated quasi-variety of De Morgan algebras and determine the bottom of the lattices of sub-quasi-varieties of Kleene and De Morgan algebras.

Different families of transport proteins catalyze transmembrane solute translocation, employing different mechanisms and energy sources. Several of these functionally dissimilar proteins nevertheless exhibit similar strutural units, consisting of six tightly packed α‐helices which may comprise all or part of a transmembrane channel. It is now recognized that some of these families arose independently of each other by convergence, while others arose from common precursors by divergence. The former families apparently arose at different times in evolutionary history, in different groups of (...) organisms, employing different routes. (shrink)

En este artículo, deseamos reflexionar sobre un punto neurálgico en nuestra realidad educativa:si no cambiamos nuestra mentalidad docente, si no modificamos nuestro accionar comoprofesores, la brecha entre la realidad social y la burbuja de cristal en la que hemos convertidoa los centros de estudio, escuelas, colegios y universidades será cada vez más grande. Con unasituación como la que planteamos, no es difícil entender algunas de las razones por las que losestudiantes no alcanzan los resultados académicos que nosotros como enseñantes deseamos (...) y,en un porcentaje alto (30 %, según los datos internos de la universidad), cambian de carrera o-lamentablemente- abandonan el proceso educativo. La transformación -necesaria y obligatoria-debe nacer de nosotros; no podemos exigírsela a nuestros estudiantes, pues es nuestraresponsabilidad hacer que sus aprendizajes sean significativos. (shrink)

David Ehrenfeld argues that humanism emphasizes reason at the expense of emotion, and that its narrow focus on the use of reason to serve human interests leads to a dichotomy between man and nature in which ecological factors are subordinated to the satisfaction of human wants. In response, I argue that: humanists stress employment of reflective reason and reason’s interrelations with other aspectsofthe human personality, humanism’s typical commitment to naturalism locates man as part of nature and does not entail an (...) exclusive focus on human interests, and humanism’s commitment to the legitimate sphere of human interests does not entail indifference to nonhuman nature, for a healthy environment is necessary for the long-term satisfaction of human interests. (shrink)

David Ehrenfeld argues that humanism emphasizes reason at the expense of emotion, and that its narrow focus on the use of reason to serve human interests leads to a dichotomy between man and nature in which ecological factors are subordinated to the satisfaction of human wants. In response, I argue that: (1) humanists stress employment of reflective reason and reason’s interrelations with other aspectsofthe human personality, (2) humanism’s typical commitment to naturalism locates man as part of nature and does not (...) entail an exclusive focus on human interests, and (3) humanism’s commitment to the legitimate sphere of human interests does not entail indifference to nonhuman nature, for a healthy environment is necessary for the long-term satisfaction of human interests. (shrink)

Evaluation is, as J. R. Maze has recently suggested, central to the concept of attitude. But it is argued that Maze's noncognitivist analysis of evaluation yields an inadequate account of our ordinary concept of attitude. A criteriological account of evaluation is sketched which allows for an objective dimension to evaluation and hence to attitudes. In the case of attitudes, it is argued that some criteria will be chosen at least in part for their consequences, and hence will not be chosen (...) solely on the basis of interest, preference or affect. (shrink)

In this paper we exhibit a non-finitely based, finitely generated quasi-variety of De Morgan algebras and determine the bottom of the lattices of sub-quasi-varieties of Kleene and De Morgan algebras.

Rationale, aims and objectives Given the increasing prevalence of cataract and demand for cataract extraction surgery, patients must often wait to undergo this procedure. We validated a previously developed priority scoring system in terms of clinical variables, pre-intervention health status, appropriateness of surgery and gain in visual acuity (VA) and health-related quality of life (HRQoL).Methods Explicit prioritization criteria for cataract extraction created by a variation of the Research and Development (RAND) and University of California Los Angeles appropriateness methodology were retrospectively (...) applied to a prospective cohort of 5257 patients on waiting lists to undergo cataract by phacoemulsification at 17 hospitals in Spain. Demographic data, clinical data and data related to surgical technique were collected by trained ophthalmologists. Patients were evaluated by their ophthalmologist before the intervention and 6 weeks afterward. They also completed, by mail, the Visual Function Index (VF-14) before the intervention and 3 months afterward.Results High-priority patients experienced greater improvement in VA and HRQoL than those classified as intermediate or low-priority (P < 0.0001), even after adjusting by VA and the VF-14 score at baseline. The time to intervention was the same for high-priority patients as it was for intermediate and low-priority patients.Conclusions The priority score we developed identified patients most likely to experience the greatest improvements from cataract extraction. Use of this tool could provide a fairer and more rational way to prioritize patients for cataract extraction. (shrink)

La humanidad se encuentra en una constante búsqueda por construir una ética que permita hacer realidad el re-ligarse con el futuro, lo cual implica generar una convivencia recíproca con la naturaleza y las demás formas de vida, en el camino de la ética del bien común. La construcción de este modelo ético se constituye en una prioridad ya que desde el mismo es posible determinar caminos de acción, que a partir de una postura social y de apoyo mutuo, se concrete (...) en alternativas para enfrentar e.. (shrink)