Some constructions of compact quantum groups

The purpose of this paper is to consider some basic constructions in the category of compact quantum groups --for example de case of extensions, of Drinfeld twists, of matched pairs, of extensions, of linked pairs and of cocycle Singer pairs -- with special emphasis in the finite dimensional situation. We give conditions, in some cases necessary and sufficient, to extend to the new objects the original compact structure. We illustrate the results in the case of matched pairs of groups

A Note on the Pseudo-Spectra and the Pseudo-Covariance Generating Functions of ARMA Processes

Although the spectral analysis of stationary stochastic processes has solid mathematical foundations, this is not the case for non-stationary stochastic processes. In this paper, the algebraic foundations of the spectral analysis of non-stationary ARMA processes are established. For this purpose the Fourier Transform is extended to the field of fractions of polynomials. Then, the Extended Fourier Transform pair pseudo-covariance generating function / pseudo-spectrum, analogous to the Fourier Transform pair covariance generating function / spectrum,is defined. The new transform pair is well defined for stationary and non-stationary ARMA processes. This new approach can be viewed as an extension of the classical spectral analysis. It is shown that the frequency domain has some additional algebraic advantages over the time domain.

El "Somnium" de Lipsio y la rebelión de los personajes del refranero en el "Sueño de la muerte" de Quevedo

My study arises from the observation of the similarities between Lipsius’ Somnium and Quevedo’s Sueño de la Muerte (1621-1622). First I will discuss Satyra Menippaea. Somnium. Lusus in nostri aevi Criticos, written in Latin by the famous Dutch humanist Iustus Lipsius and published in Antwerp in 1581. This work reintroduces the Greco-Roman genre ofMenippean satire. Then I will provide plausible explanations of the textual and ideological influences that Lipsius’ text could have had on Quevedo’s final passage of Sueño de la muerte, in which a series of folkloric characters rise up and argue against the incorrect and malicious ways that the living make use of them. That passage is refered to here as «La rebelión de los personajes del refranero».Mi estudio surge de la observación de similitudes entre el Somnium de Lipsio (1581) y el Sueño de la Muerte de Quevedo (1621-1622). En primer lugar presento y analizo la obra en latín del humanista holandés Justo Lipsio, Satyra Menippaea. Somnium. Lusus in nostri aevi Criticos, publicada en Amberes en 1581, que reinicia en la modernidad el género grecolatino de la sátira menipea. En segundo lugar daré cuenta de las influencias textuales e ideológicas que pudo haber tenido el texto de Lipsio sobre el Sueño de la Muerte de Quevedo y, en especial, sobre su pasaje final, en el que una serie de personajes folklorizados alzan su queja y esgrimen su defensa frente al uso incorrecto y malicioso que los vivos hacen de ellos. Me refiero a este pasaje como «La rebelión de los personajes del refranero»

Statistical approaches for natural language modelling and monotone statistical machine translation

Esta tesis reune algunas contribuciones al reconocimiento de formas estadístico y, más especícamente, a varias tareas del procesamiento del lenguaje natural. Varias técnicas estadísticas bien conocidas se revisan en esta tesis, a saber: estimación paramétrica, diseño de la función de pérdida y modelado estadístico. Estas técnicas se aplican a varias tareas del procesamiento del lenguajes natural tales como clasicación de documentos, modelado del lenguaje natural y traducción automática estadística. En relación con la estimación paramétrica, abordamos el problema del suavizado proponiendo una nueva técnica de estimación por máxima verosimilitud con dominio restringido (CDMLEa ). La técnica CDMLE evita la necesidad de la etapa de suavizado que propicia la pérdida de las propiedades del estimador máximo verosímil. Esta técnica se aplica a clasicación de documentos mediante el clasificador Naive Bayes. Más tarde, la técnica CDMLE se extiende a la estimación por máxima verosimilitud por leaving-one-out aplicandola al suavizado de modelos de lenguaje. Los resultados obtenidos en varias tareas de modelado del lenguaje natural, muestran una mejora en términos de perplejidad. En a la función de pérdida, se estudia cuidadosamente el diseño de funciones de pérdida diferentes a la 0-1. El estudio se centra en aquellas funciones de pérdida que reteniendo una complejidad de decodificación similar a la función 0-1, proporcionan una mayor flexibilidad. Analizamos y presentamos varias funciones de pérdida en varias tareas de traducción automática y con varios modelos de traducción. También, analizamos algunas reglas de traducción que destacan por causas prácticas tales como la regla de traducción directa; y, así mismo, profundizamos en la comprensión de los modelos log-lineares, que son de hecho, casos particulares de funciones de pérdida. Finalmente, se proponen varios modelos de traducción monótonos basados en técnicas de modelado estadístico .Andrés Ferrer, J. (2010). Statistical approaches for natural language modelling and monotone statistical machine translation [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/7109Palanci

Modulación de propiedades optoelectrónicas de materiales basados en grafeno y nanopuntos de carbono

Tesis de la Universidad Complutense de Madrid, Facultad de Ciencias Químicas, Departamento de Química Orgánica, leída el 07-06-2019Nowadays, the degradation of the environment and the climate change are some of the main concerns of our society. Therefore, a lot of effort has been invested in the search for new alternatives to fossil fuels. One interesting solution to this problem is to use solar energy as a renewable supply. In nature, it is well-known that solar energy can be transformed into chemical energy by means of photosynthetic processes. This concept has inspired a lot of efforts in the development of new artificial photosynthetic systems composed by donoracceptor(D-A) assemblies. Specifically, in recent years, the combination of carbon nanoforms and light-harvesting dyes using covalent and supramolecular approaches has been widely studied. In this sense, the improvement in the formation methodology of new D-A assemblies, as well as the understanding of the charge transfer processes involved in these systems, are the main keys to create new artificial systems with a potential applicability...Actualmente, unas de las mayores preocupaciones de nuestra sociedad son la degradación del medio ambiente y el cambio climático. Debido a esto, se ha invertido mucho esfuerzo en la búsqueda de nuevas alternativas a los combustibles fósiles. Una solución interesante a este problema es el uso de la energía solar como fuente de energía renovable. Como bien sabemos, los procesos fotosintéticos observados en la naturaleza son capaces de transformarla energía solar en energía química. Buscando inspiración en este concepto, se ha puesto mucho esfuerzo en el desarrollo de nuevos sistemas foto sintéticos artificiales basados en complejos de tipo dador-aceptor (D-A). Concretamente, en los últimos años, ha sido muy estudiada la formación de sistemas basados en nanoformas de carbono y colorantes con gran capacidad de absorción de luz, a través de estrategias covalentes y supramoleculares. En este sentido, las claves para la creación de sistemas artificiales con una potencial aplicabilidad son la mejora de las metodologías para la formación de los sistemas D-A, así como la comprensión de los procesos de trasferencia de carga que operan en este tipo de sistemas...Depto. de Química OrgánicaFac. de Ciencias QuímicasTRUEunpu

Constrained domain maximum likelihood estimation and the loss function in statistical pattern recognition

In this thesis we present a new estimation algorithm for statistical models which does not incurs in the over-trainning problems. This new estimation techinque, the so-called, constrained domain maximum likelihood estimation (CDMLE) holds all the theoretical properties of the maximum likelihood estimation and furthermore it does not provides overtrained parameter sets. On the other hand, the impliations of the the 0-1 loss function assumption are analysed in the pattern recognition tasks. Specifically, more versatile functions are designed without increasing the optimal classification rule costs. This approach is applied to the statistical machine translation problem.Andrés Ferrer, J. (2008). Constrained domain maximum likelihood estimation and the loss function in statistical pattern recognition. http://hdl.handle.net/10251/13638Archivo delegad

White matter alterations in Alzheimer’s disease without concomitant pathologies

Aims: Most individuals with AD neuropathological changes have co-morbidities which have an impact on the integrity of the WM. This study analyses oligodendrocyte and myelin markers in the frontal WM in a series of AD cases without clinical or pathological co-morbidities. Methods: From a consecutive autopsy series, 206 cases had neuropathological changes of AD; among them, only 33 were AD without co-morbidities. WM alterations were first evaluated in coronal sections of the frontal lobe in every case. Then, RT-qPCR and immunohistochemistry were carried out in the frontal WM of AD cases without co-morbidities to analyse the expression of selected oligodendrocyte and myelin markers. Results: WM demyelination was more marked in AD with co-morbidities when compared with AD cases without co-morbidities. Regarding the later, mRNA expression levels of MBP, PLP1, CNP, MAG, MAL, MOG and MOBP were preserved at stages I-II/0-A when compared with middle-aged (MA) individuals, but significantly decreased at stages III-IV/0-C. This was accompanied by reduced expression of NG2 and PDGFRA mRNA, reduced numbers of NG2-, Olig2- and HDAC2-immunoreactive cells and reduced glucose transporter immunoreactivity. Partial recovery of some of these markers occurred at stages V-VI/B-C. Conclusions: The present observations demonstrate that co-morbidities have an impact on WM integrity in the elderly and in AD, and that early alterations in oligodendrocytes and transcription of genes linked to myelin proteins in WM occur in AD cases without co-morbidities. These are followed by partial recovery attempts at advanced stages. These observations suggest that oligodendrocytopathy is part of AD

Delineating the efficacy of a cannabis-based medicine at advanced stages of dementia in a murine model

Previous reports have demonstrated that the combination of Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD) botanical extracts, which are the components of an already approved cannabis-based medicine, reduce the Alzheimer-like phenotype of AβPP/PS1 transgenic mice when chronically administered during the early symptomatic stage. Here, we provide evidence that such natural cannabinoids are still effective in reducing memory impairment in AβPP/PS1 mice at advanced stages of the disease but are not effective in modifying the Aβ processing or in reducing the glial reactivity associated with aberrant Aβ deposition as occurs when administered at early stages of the disease. The present study also demonstrates that natural cannabinoids do not affect cognitive impairment associated with healthy aging in wild-type mice. The positive effects induced by Δ9-THC and CBD in aged AβPP/PS1 mice are associated with reduced GluR2/3 and increased levels of GABA-A Rα1 in cannabinoid-treated animals when compared with animals treated with vehicle alone

Genetic deletion of CB1 cannabinoid receptors exacerbates the Alzheimer-like symptoms in a transgenic animal model

Activating CB1 cannabinoid receptor has been demonstrated to produce certain therapeutic effects in animal models of Alzheimer's disease (AD). In this study, we evaluated the specific contribution of CB1 receptor to the progression of AD-like pathology in double transgenic APP/PS1 mice. A new mouse strain was generated by crossing APP/PS1 transgenic mice with CB1 knockout mice. Genetic deletion of CB1 drastically reduced the survival of APP/PS1 mice. In spite that CB1 mutant mice bearing the APP/PS1 transgene developed normally, they suddenly died within the first two months of life likely due to spontaneous seizures. This increased mortality could be related to an imbalance in the excitatory/inhibitory transmission in the hippocampus as suggested by the reduced density of inhibitory parvalbumin positive neurons observed in APP/PS1 mice lacking CB1 receptor at 7 weeks of age. We also evaluated the AD-like phenotype of APP/PS1 mice heterozygous for the CB1 deletion at 3 and 6 months of age. The memory impairment associated to APP/PS1 transgene was accelerated in these mice. Neither the soluble levels of Aβ or the density of Aβ plaques were modified in APP/PS1 mice heterozygous for CB1 deletion at any age. However, the reduction in CB1 receptor expression decreased the levels of PSD-95 protein in APP/PS1 mice, suggesting a synaptic dysfunction in these animals that could account for the acceleration of the memory impairment observed. In summary, our results suggest a crucial role for CB1 receptor in the progression of AD-related pathological events

El somni de Sant Josep de Francesc Ribalta a Algemesí. Una obra retrobada arran de la seua desaparició durant la Guerra Civil,

En el año 2010 la Galería Caylus de Madrid ponía a la venta una tabla titulada El sueño de san José, atribuida a Francisco Ribalta, procedente del retablo de San José de la iglesia parroquial de Algemesí y desaparecida durante la Guerra Civil. El presente artículo pretende realizar un estudio de la obra analizándola desde varias disciplinas (documentación, historia del arte, análisis químico, iconografía) para confirmar que esta pintura reaparecida recientemente fue realizada por este artista y es, efectivamente, la que desapareció de Algemesí durante el conflicto bélico.In 2010 the Caylus Gallery in Madrid put on sale a painting titled The dream of St. Joseph, attributed to Francisco Ribalta, from the altarpiece of St. Joseph, in the parish church of Algemesí which disappeared during the Civil War. This article aims to conduct a study of the work analyzing it from various disciplines (history of art, chemical analysis, iconography, documentation) to confirm that this recently appeared painting was in fact by this artist and is, effectively, the one that disappeared from Algemesí during the war