315 research outputs found
Pion scattering poles and chiral symmetry restoration
Using unitarized Chiral Perturbation Theory methods, we perform a detailed
analysis of the scattering poles and behaviour
when medium effects such as temperature or density drive the system towards
Chiral Symmetry Restoration. In the analysis of real poles below threshold, we
show that it is crucial to extend properly the unitarized amplitudes so that
they match the perturbative Adler zeros. Our results do not show threshold
enhancement effects at finite temperature in the channel, which
remains as a pole of broad nature. We also implement T=0 finite density effects
related to chiral symmetry restoration, by varying the pole position with the
pion decay constant. Although this approach takes into account only a limited
class of contributions, we reproduce the expected finite density restoration
behaviour, which drives the poles towards the real axis, producing threshold
enhancement and bound states. We compare our results with several
model approaches and discuss the experimental consequences, both in
Relativistic Heavy Ion Collisions and in and
reactions in nuclei.Comment: 17 pages, 9 figures, final version to appear in Phys.Rev.D, added
comments and reference
Cultivos forestales y cambio tecnológico. Efectos económicos y ambientales
This article analyzes the impact of the expansion of forest plantations on the world forestry sector. The transition process from a resource-base to a science-base wood production system is described and the main factors conditioning actual wood production world wide are also identified. A simple analytical framework is used to analyze the potential contribution of intensive plantations and technical change to world wood supply and the conservation of forest resources.Este artículo analiza las repercusiones de la expansión de los cultivos forestales sobre el sector forestal mundial. Se describe, en primer lugar, el proceso de transición de unos sistemas de producción de madera basados, esencialmente, en la extracción de recursos naturales, a unas producciones madereras cada vez más intensivas en innovaciones tecnológicas-recursos del conocimiento. A continuación se identifican los principales factores que condicionan en la actualidad la producción de madera destinada a uso industrial. Se desarrolla también un marco analítico sencillo que incorpora el cambio tecnológico, mediante el cual es posible analizar la contribución potencial de los cultivos forestales intensivos sobre la oferta mundial de madera y la conservación de los recursos forestales
Demonología en la "Expositio Super Iob" de Santo Tomás de Aquino
Orvieto, 1261-1264. En este tiempo y lugar, según los datos más
seguros, Santo Tomás de Aquino impartió un ciclo de clases comentando
uno de los libros sagrados de más difícil interpretación: el libro
de Job.
En 1981 —junto con otros dos doctorandos— realizamos la
traducción al castellano de la Expositio super Iob ad litteram. A
medida que avanzaba la traducción nos dimos cuenta de la riqueza
teológica que contenía este comentario del Aquinatense. La providencia
divina, el sufrimiento del justo, la coordinación libertadgracia,
el problema del mal, la amistad, el valor del dolor, la vida
futura, etc., son cuestiones que el Doctor Angélico expone a lo
largo de todo el comentario a Job. La exposición no la hace sistemáticamente,
sino que brota al hilo de los versículos comentados.
El Aquinatense no pretende hacer un tratado sistemático de tales
cuestiones, sólo quiere comentar el libro de Job
UCO.MIPSIM: pipelined computer simulator for teaching purposes
Since pipelining is a very important implementation technique for processors,
students in Computer Science need to achieve a good understanding of it.
UCO.MIPSIM simulator has been developed to support teaching such concepts.
This paper introduces the basics of pipelining and describes UCO.MIPSIM, its
main components and its functions. The learning effectiveness of the simulator has
been tested by means of the comparison with two learning tools, the traditional
paper and pencil and another pipelined computer simulator. In this way, a tool
evaluation methodology is also introduce
Anaerobic co-digestion of pear residues and sewage sludge using a CSTR digester. Influence of the feed procedure
Anaerobic co-digestion of pear residues with sewage sludge is feasible.
Important differences are obtained from the two feed regimes tested, with better results for the
so-called continuous feed.
The organic loading rate (OLR) is the important parameter for the methane productionUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
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