From conformal to volume-law for the entanglement entropy in exponentially deformed critical spin 1/2 chains

An exponential deformation of 1D critical Hamiltonians gives rise to ground states whose entanglement entropy satisfies a volume-law. This effect is exemplified in the XX and Heisenberg models. In the XX case we characterize the crossover between the critical and the maximally entangled ground state in terms of the entanglement entropy and the entanglement spectrum.Comment: Accepted for the Special Issue: Quantum Entanglement in Condensed Matter Physics. 11 pages, 9 figures (with enhanced size to focus on the details) and new reference

MEXICAN FLORICULTURE IN THE 21ST CENTURY: ITS PERFORMANCE IN INTERNATIONAL MARKETS

El mercado mundial de la floricultura presenta, en general, una tendencia de crecimiento. Sin embargo, es diferente lo que sucede en el sector exportador y el importador. El primero tiene concentrado en un exportador casi la mitad del mercado, además de presentar nuevos oferentes con alto ritmo de expansión, en tanto que el segundo mantiene a los compradores tradicionales. Por su parte, México tiene muy baja presencia en este mercado, la participación porcentual de las exportaciones e importaciones de la floricultura mexicana representan menos de medio punto.En las décadas finales del siglo XX, en México se buscaron actividades económicas rentables en el sector agropecuario, dado que cultivos tradicionales y con baja productividad no permitían mejoras de las zonas rurales. La floricultura, en especial sur del Estado de México, Morelos, Puebla y Distrito Federal, se fomentó con miras a incrementar ingresos de los productores al comercializar dentro y fuera del país. El crecimiento del comercio exterior de la floricultura ha sido reducido pues se exporta alrededor de diez por ciento de lo cultivado. Así, el objetivo del presente documento es analizar el desempeño de la floricultura mexicana en los mercados internacionales en los primeros años del siglo actual. El referente teórico en el comercio internacional se basa en el análisis del dinamismo de la floricultura mexicana en el comercio exterior con indicadores de apertura económica, concentración del comercio y complementariedad. La metodología consiste en el cálculo de dichos indicadores para determinar la situación y los cambios de México en el mercado internacional de la floricultura. Los resultados señalan que existe un moderado nivel de apertura económica del sector, una alta concentración del comercio mexicano con Estados Unidos (lo que refleja una baja diversificación) y la complementariedad es baja. Se concluye que, el comercio internacional de la floricultura mexicana, es poco relevante en el mercado internacional y está concentrado en Estados Unidos, a mediano plazo podría haber un escenario de déficit permanente dados los componentes de la balanza comercial

Automatic Text Summarization Approaches to Speed up Topic Model Learning Process

The number of documents available into Internet moves each day up. For this reason, processing this amount of information effectively and expressibly becomes a major concern for companies and scientists. Methods that represent a textual document by a topic representation are widely used in Information Retrieval (IR) to process big data such as Wikipedia articles. One of the main difficulty in using topic model on huge data collection is related to the material resources (CPU time and memory) required for model estimate. To deal with this issue, we propose to build topic spaces from summarized documents. In this paper, we present a study of topic space representation in the context of big data. The topic space representation behavior is analyzed on different languages. Experiments show that topic spaces estimated from text summaries are as relevant as those estimated from the complete documents. The real advantage of such an approach is the processing time gain: we showed that the processing time can be drastically reduced using summarized documents (more than 60\% in general). This study finally points out the differences between thematic representations of documents depending on the targeted languages such as English or latin languages.Comment: 16 pages, 4 tables, 8 figure

Auditoría y análisis del estándar HTML5 y su uso en páginas web

Este proyecto aborda la auditoría y el análisis del estándar HTML5, comprobando sus fortalezas y vulnerabilidades. Pretende ser una guía de referencia en las debilidades del lenguaje dentro del marco de discusión que recomienda la W3C, que es el consorcio responsable del desarrollo del código del nuevo formato. Comienza con una introducción a la auditoría informática enfocada a la web, los posibles peligros y amenazas, las políticas y normas legales que han de cumplir los proyectos en este medio. Luego prosigue con una explicación de HTML5, desde sus inicios, pasando por el proceso de estandarización en el W3C, sus diferencias con respecto al estándar anterior, HTML 4.01, y el futuro estándar, HTML 5.1, su implementación actual y sus barreras de entrada. Finalmente profundiza en el análisis y la auditoría de la nueva versión de HTML. Evaluando su seguridad, fallos, agujeros que pueden ser utilizados por personas malintencionadas, debilidades debidas a las nuevas funcionalidades y puntos a reforzar con vista al futuro. También examina su usabilidad, si realmente todas las innovaciones mejorarán la accesibilidad y la claridad en el desarrollo web. Y por último comprueba que cumple con las normativas, estándares y leyes relacionadas que se encuentran actualmente en vigor.This research project tackles the problem of how to audit the HTML5 standard. It includes as well an in depth analysis of the standard, focusing on its strengths and vulnerabilities. The aim of the project is to identify its possible flaws. W3C is the consortium responsible of designing the framework to implement this new standard, and it strongly advices that HTML5 should be analyzed to identify and solve any difficulties hindering its performance. During the first stage of the research, an analysis of the web based development will be undertaken, with the focus set on an introduction on how to audit this kind of informatics projects, threats and vulnerabilities that might appear and the legal framework that has to be followed. The next stage covers the HTML5 Domain Knowledge Capture, staring from the very moment it was first conceived, dealing with its standardization process with W3C and finally analyzing its differences with the existing HTML 4.01 and the future standard, HTML 5.1, and any issues regarding its successful implementation. The following step is to further dig into the new HTML version, and study it in depth. Flaws and holes in security that may be exploitable, vulnerabilities of the new functionalities and possible enhancements that would be convenient as part of the future work of the project. Furthermore, it covers its usability, the impact that the different innovative techniques will have within the web based development framework: compatibility, accessibility, user friendliness… The project will finally check if HTML5 fulfills all the legal requirements as well as the existing standards.Ingeniería Técnica en Informática de Gestió

Dinámica cardiaca del adulto evaluada mediante las proporciones de la entropía

Introduction: A new mathematical methodology of clinical application has been developed from the theory of dynamic systems, together with the theory of probability and the concept of entropy. Objective: To apply the methodology previously developed to evaluate the heart dynamics of adult through the probability and proportions of entropy of the attractor. Materials and methods: A blind study was developed taking as Gold Standard the conventional diagnosis issued by an expert with 480 Holter, 30 normal dynamics and 450 with different pathologies. For each Holter, a numerical attractor was generated by quantifying the probability of appearance of consecutive pairs of cardiac frequencies, subsequently evaluating entropy, S/K ratio and proportions for each dynamic for at least 18 hours. The values of sensitivity, specificity and Kappa coefficient were found. Results: The applied methodology allowed to differentiate quantitatively normality of disease, finding the values of the proportions in the established ranges. The sensitivity and specificity values were 100%, and Kappa coefficient was 1. Conclusion: It is possible to diagnose cardiac dynamics for at least 18 hours based on the probability distributions of the appearance of consecutive pairs of cardiac frequencies and their entropy

SEQUENTIAL INDUCTION OF CHIRALITY IN POLY(PHENYLACETYLENE)S

Several hierarchical levels of chirality have been detected in functionalized poly(phenylacetylene)s (PPA).1 In this work we have studied the chirality induction throughout these levels in PPA functionalized with phenylglycine methyl ester groups, Fig. 1.2 These pendant groups force the PPA chain to lose its planar all-transoid shape to form helical structures. The chiral seed of the pendants, [(R)- or (S)-], dictates the preferent handedness of the helices, both the internal polyacetylene helical covalent backbone and the external helix formed by the side pendants which forms a complementary helix or counter-helix. In this work, we afford a full assessment of the interconnection between stereocenter and helix sources of chirality and the action of these polymers as chiral templates of other supra-molecular structures with inherited chiral properties. We then used VCD spectroscoy to demonstrate the chiral induction from the stereogenic centers to the backbone helix and from this to the pendant helix, which are largely promoted by two mechanisms: steric effects and hydrogen bonding. In addition, the VCD spectra supported that the helical setup of the pendants induces the solvent DMSO molecules to adopt a solvation helix around the polymer, thus proving how an achiral solvent becomes chirally organized owing to the template effect of the covalent polymer helices. A similar effect was observed in DMSO solutions of the monomeric units. Interestingly, this resulted in opposite helical sense to the one observed in the polymer with identical enantiomeric form.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Mexican Floriculture at the Dawn of the Twenty-First Century: Its Position and Dynamism in International Markets

Ramírez Hernández, Javier Jesús and Avitia Rodríguez, Jessica Alejandra and Urbina, Erika Yanet Castro, Mexican Floriculture at the Dawn of the Twenty-First Century: Its Position and Dynamism in International Markets (February 21, 2017). XVI International Business & Economy Conference (IBEC) - Chile 2017. Available at SSRN: https://ssrn.com/abstract=2921019In last decades of the 20th century, in Mexico there were looked economic profitable activities inside the agricultural sector, due to the fact that the traditional plantations with low productivity do not stimulate an improvement of the conditions of rural zones. The flower growing, in the south of the State of Mexico, Morelos, Puebla and Distrito Federal, it was promoted by the intention of increasing the income of the producers commercializing inside and out of the country. The growth of the international trade of the flower growing has been reduced so there is exported about ten per cent of the harvested plants. The aim of the present document is to analyze the position and the dynamics of the Mexican flower growing on the international markets in the first years of the present century. The theoretical frame in the international trade is based on the analysis of the activity of the Mexican flower growing on the international trade on topics of economic opening and concentration of the trade. The methodology consists of the calculation of indicators to determine the situation and the changes of Mexico on the international market of the flower growing. The results indicate that there exists a moderate level of economic opening of the sector and exists high concentration of the Mexican trade with United States (it reflects a low diversification). One concludes that the international trade of the Mexican flower growing is slightly relevant on the international market and is concentrated in The United States, to medium term there might be a scene of permanent deficit given the components of the commercial scale