The Samuel realcompactification of a metric space

In this paper we introduce a realcompactification for any metric space (X, d), defined by means of the family of all its real-valued uniformly continuous functions. We call it the Samuel realcompactification, according to the well known Samuel compactification associated to the family of all the bounded real-valued uniformly continuous functions. Among many other things, we study the corresponding problem of the Samuel realcompactness for metric spaces. At this respect, we prove that a result of Katetov-Shirota type occurs in this context, where the completeness property is replaced by Bourbaki-completeness (a notion recently introduced by the authors) and the closed discrete subspaces are replaced by the uniformly discrete ones. More precisely, we see that a metric space (X, d) is Samuel realcompact iff it is Bourbaki-complete and every uniformly discrete subspace of X has non-measurable cardinal. As a consequence, we derive that a normed space is Samuel realcompact iff it has finite dimension. And this means in particular that realcompactness and Samuel realcompactness can be very far apart. The paper also contains results relating this realcompactification with the so-called Lipschitz realcompactification (also studied here), with the classical Hewitt-Nachbin realcompactification and with the completion of the initial metric space

A Theoretical Framework for Lagrangian Descriptors

This paper provides a theoretical background for Lagrangian Descriptors (LDs). The goal of achieving rigourous proofs that justify the ability of LDs to detect invariant manifolds is simplified by introducing an alternative definition for LDs. The definition is stated for $n$-dimensional systems with general time dependence, however we rigorously prove that this method reveals the stable and unstable manifolds of hyperbolic points in four particular 2D cases: a hyperbolic saddle point for linear autonomous systems, a hyperbolic saddle point for nonlinear autonomous systems, a hyperbolic saddle point for linear nonautonomous systems and a hyperbolic saddle point for nonlinear nonautonomous systems. We also discuss further rigorous results which show the ability of LDs to highlight additional invariants sets, such as $n$-tori. These results are just a simple extension of the ergodic partition theory which we illustrate by applying this methodology to well-known examples, such as the planar field of the harmonic oscillator and the 3D ABC flow. Finally, we provide a thorough discussion on the requirement of the objectivity (frame-invariance) property for tools designed to reveal phase space structures and their implications for Lagrangian descriptors

Blockade of the Interaction of Calcineurin with FOXO in Astrocytes Protects Against Amyloid-βInduced Neuronal Death

Astrocytes actively participate in neuro-inflammatory processes associated to Alzheimer’s disease (AD), and other brain pathologies. We recently showed that an astrocyte-specific intracellular signaling pathway involving an interaction of the phosphatase calcineurin with the transcription factor FOXO3 is a major driver in AD associated pathological inflammation, suggesting a potential new druggable target for this devastating disease. We have now developed decoy molecules to interfere with calcineurin/FOXO3 interactions, and tested them in astrocytes and neuronal co-cultures exposed to amyloid-β (Aβ) toxicity. We observed that interference of calcineurin/FOXO3 interactions exerts a protective action against A-induced neuronal death and favors the production of a set of growth factors that we hypothesize form part of a cytoprotective pathway to resolve inflammation. Furthermore, interference of the A-induced interaction of calcineurin with FOXO3 by decoy compounds significantly decreased amyloid-β protein precursor (AβPP) synthesis, reduced the AβPP amyloidogenic pathway, resulting in lower Alevels, and blocked the expression of pro-inflammatory cytokines TNFα and IL-6 in astrocytes. Collectively, these data indicate that interrupting pro-inflammatory calcineurin/FOXO3 interactions in astrocytes triggered by Aβ accumulation in brain may constitute an effective new therapeutic approach in AD. Future studies with intranasal delivery, or brain barrier permeable decoy compounds, are warranted

Evaluar la creatividad para potenciar las habilidades sociales en educación musical para adultos

La creatividad, inseparable de cualquier actividad artística, se puede convertir en un recurso para afrontar los desafíos a los que nos enfrentamos en la vida, tanto a nivel personal como profesional, desarrollando, esta actividad artística, habilidades que promueven la creatividad y la sociabilidad. Desde la perspectiva social, la música permite la interrelación entre un determinado grupo, proporcionando la cohesión así como el desarrollo en las HHSS. En este trabajo decidimos averiguar si nuestro alumnado de educación musical era competente en creatividad, para así poder mejorar en su aprendizaje, incrementando la motivación y potenciando la actitud crítica, activa y participativa

The adsorbent capacity of growing media does not constrain myo-inositol hexakiphosphate hydrolysis but its use as a phosphorus source by plants

Aims The hydrolysis of organic P in soils is a relevant aspect contributing to the supply P to plants, which is affected by adsorbent capacity and biological properties of soils. This work aimed at studying the contribution of phytate to plant nutrition as affected by Fe oxides and phosphohydrolases releasing microorganisms in the growing medium. Methods An experiment with cucumber and myo-inositol hexakiphosphate (myo-Ins6P) as P source was performed involving two factors: Fe oxide –ferrihydrite– rates (0, 100, 300 mg kg−1 of citrate–ascorbate extractable Fe), and microbial inoculation (Trichoderma asperellum T34, Bacillus subtilis QST713, and noninoculated). Results P uptake decreased with increased Fe oxides in the growing media. Phytase activity and organic anions concentration increased with increased Fe oxides in the media. Most of the P supplied was recovered as inorganic P at the highest Fe oxide concentration. Inoculants did not improve P uptake by plants, despite B. subtilis promoted an enhanced hydrolytic activity at the highest Fe oxide concentration. Conclusions An increased adsorption capacity of the growing media restricts the use of myo-Ins6P as P source by plants. This was not the result of its stabilization through adsorption or a decreased hydrolytic activity, but of the adsorption of inorganic P on Fe oxides after hydrolysis

An Electrochemical Outlook on Tamoxifen Biotransformation: Current and Future Prospects

Tamoxifen is a nonsteroidal antiestrogen that is currently and widely used in the treatment of breast cancer in all of its stages, in adjuvant therapy as a long-term suppressant of tumor recurrence and also as a chemopreventive agent in women that are in high risk of developing this type of estrogen-dependent cancer. From a toxicological and (bio)analytical point of view the knowledge of the metabolic pathways of a drug is found to be extremely important. So, in the present work the most important tamoxifen biotransformation steps were reviewed in the light of recent pharmacological data. This overview also includes the current controversy concerning tamoxifen DNA-damaging (genotoxic) versus non-genotoxic mechanisms. A special focus will be given to the putative application of electrochemical methods as a modern and reliable analytical tool for determination of tamoxifen and its metabolites. Moreover, the potential of DNA electrochemical sensors for detection of structural damage to DNA as a basis for toxicity screening is highlighted. Future prospects looking for the importance of developing new analytical methodologies are also discussed.info:eu-repo/semantics/publishedVersio

Necesidades de información meteorológica en el sector agrario

Presentación realizada en: Jornada sobre "Servicios meteorológicos y climáticos para el sector agrario", celebrada el 30 de mayo de 2013 en la sede central de AEMET en Madri