Recent Applications of Self-Consistent Green's Function Theory to Nuclei

We discuss recent \emph{ab initio} calculations based on self-consistent Green's function theory. It is found that a simple extension of the formalism to account for two-nucleon scattering outside the model space allows to calculate non-soft interactions. With this, it is possible to make predictions for Lattice QCD potentials, obtained so far at pion masses of $m_\pi = 0.47$GeV/c$^2$. More traditional calculations that use saturating chiral EFT forces yield a good description of nuclear responses and nucleon knockout spectroscopy.Comment: 6 pages, 5 figures, Ischia conference proceedin

Toward a Transnational Perspective on Seattle’s Japantown: Nagai Kafū’s American Stories

The aim of this paper is to provide a short analysis of the literary representation of the Japantown that evolved in Seattle toward the end of the nineteenth and the beginning of the twentieth centuries, as portrayed by Japanese writer Nagai Kafū in Amerika monogatari (“American Stories”), a collection of short stories and autobiographical sketches based on the author’s experience in the United States, written in the first years of the twentieth century. The author's description and narration of the buildings, life, and people of Japantown provide a detailed idea of the socio-historical realities present in the area of the United States where the first Japanese immigrants arrived and settled

¿Es satírico este tweet? Un método automático para la identificación del lenguaje satírico en español

Computational approaches to analyze figurative language are attracting a growing interest in Computational Linguistics. In this paper, we study the characterization of Twitter messages in Spanish that advertise satirical news. We present and evaluate a system able to classify tweets as satirical or not. To this purpose, we concentrate on the tweets published by several satirical and non-satirical Twitter accounts. We model the text of each tweet by a set of linguistically motivated features that aim at capturing the style more than the content of the message. Our experiments demonstrate that our model outperforms a word-based baseline. We also demonstrate that our system models global features of satirical language by showing that it is able to detect if a tweet contains or not satirical contents independently from the account that generated the tweet.La lingüística computacional está cada vez más interesada en el procesamiento del lenguaje figurado. En este artículo estudiamos la detección de noticias satíricas en español y más específicamente la detección de sátira en mensajes de Twitter. Nuestro modelo computacional se basa en la representación de cada mensaje con un conjunto de rasgos diseñados para detectar el estilo satírico y no el contenido. Nuestros experimentos muestran que nuestro modelo siempre funciona mejor que un modelo de bolsa de palabras. También mostramos que el sistema es capaz de detectar este tipo de lenguaje independientemente de la cuenta de Twitter que lo origina.The research described in this paper is partially funded by the SKATER-UPF-TALN project (TIN2012-38584-C06-03)

Complex dynamics of circular cylindrical shells

Complex dynamics of circular cylindrical shells subjected to inertial axial loads are investigated. The shell is vertically mounted on a shaker, i.e. its base is clamped to the shaker fixture, which induces a vertical motion along the shell axis. On the top of the shell a rigid disk is mounted, the vertical motion induced by the shaker induces huge inertial forces due to the rigid body motion. A complicating effect is due to the base actuator, which is an electro-dynamic shaking table; the interaction between the shell and shaker dynamics changes dramatically the system behaviour. The non-linear Sanders–Koiter theory is considered for the structural dynamics: the resulting set of non-linear partial differential equations is coupled with the linear ordinary differential equations that govern the shaker dynamics. A deep analysis of the non-stationary response of the shell is carried out in order to clarify the transition from stationary to non-stationary response. The model is validated by means of experimental results

Resumen y extracción de información en tu Tablet

In this article we present a Web-based demonstration of on-line text summarization and information extraction technology. News summarization in Spanish has been implemented in a system that monitors a news provider and summarizes the latest published news. The possibility to generate summaries from user's provided text is also available for English and Spanish. The demonstrator also features event extraction functionalities since it identifies the relevant concepts that characterize several types of events by mining English textual contents.En este artículo describimos la demonstración de una serie de aplicaciones de resumen automático y extracción de informaciones integradas en una tableta. Se presentan funcionalidades para resumir las últimas noticias publicadas en la Web, extraer información sobre eventos concretos, y resumir textos en inglés y español ingresados por el usuario. La aplicación está disponible en un Web-browser y una tableta con sistema operativo Android.We acknowledge support from the Spanish research project SKATER-UPF-TALN TIN2012-38584-C06-03, the EU project Dr. Inventor FP7-ICT-2013.8.1 611383, and UPF projects PlaQUID 65 2013-2014 and PlaQUID 47 2011-2012

Experimental Realization of Polarization Qutrits from Non-Maximally Entangled States

Based on a recent proposal [Phys. Rev. A 71, 062337 (2005)], we have experimentally realized two photon polarization qutrits by using non-maximally entangled states and linear optical transformations. By this technique high fidelity mutually unbiased qutrits are generated at a high brilliance level.Comment: RevTex, 8 pages, 6 figure

Low Energy Implications of Minimal Superstring Unification

We study the phenomenological implications of effective supergravities based on string vacua with spontaneously broken N=1 supersymmetry by dilaton and moduli $F$-terms. We further require Minimal String Unification, namely that large string threshold corrections ensure the correct unification of the gauge couplings at the grand unification scale. The whole supersymmetric mass spectrum turns out to be determined in terms of only two independent parameters, the dilaton-moduli mixing angle and the gravitino mass. In particular we discuss the region of the parameter space where at least one superpartner is ``visible" at LEP2. We find that the most likely candidates are the scalar partner of the right-handed electron and the lightest chargino, with interesting correlations between their masses and with the mass of the lightest higgs. We show how discovering SUSY particles at LEP2 might rather sharply discriminate between scenarios with pure dilaton SUSY breaking and mixed dilaton-moduli breaking.Comment: 11 pages, LaTEX, psfig, 8 figure

Dynamics and Stability of Carbon Nanotubes

The low-frequency oscillations and energy localization of Single-Walled Carbon Nanotubes (SWNTs) are studied in the framework of the Sanders-Koiter shell theory. The circumferential flexure modes (CFMs) are analysed. Simply supported, clamped and free boundary conditions are considered. Two different approaches are proposed, based on numerical and analytical models. The numerical model uses in the linear analysis a double mixed series expansion for the displacement fields based on Chebyshev polynomials and harmonic functions. The Rayleigh-Ritz method is applied to obtain approximate natural frequencies and mode shapes. In the nonlinear analysis, the three displacement fields are re-expanded by using approximate eigenfunctions. An energy approach based on Lagrange equations is considered in order to obtain a set of nonlinear ordinary differential equations, which is solved by the Runge-Kutta numerical method. The analytical model considers a reduced version of the Sanders-Koiter shell theory obtained by assuming small circumferential and tangential shear deformations. These two assumptions allow to condense the longitudinal and circumferential displacement fields into the radial one. A nonlinear fourth-order partial differential equation for the radial displacement field is derived, which allows to calculate the natural frequencies and to estimate the nonlinearity effect. An analytical solution of this equation is obtained by the multiple scales method. The previous models are validated in linear field by means of comparisons with experiments, molecular dynamics simulations and finite element analyses retrieved from the literature. The concept of energy localization in SWNTs is introduced, which is a strongly nonlinear phenomenon. The low-frequency nonlinear oscillations of the SWNTs become localized ones if the intensity of the initial excitation exceeds some threshold which depends on the SWNTs length. This localization results from the resonant interaction of the zone-boundary and nearest nonlinear normal modes leading to the confinement of the vibration energy in one part of the system. The value of the initial excitation corresponding to this energy confinement is referred to as energy localization threshold. The effect of the aspect ratio on the analytical and numerical values of the energy localization threshold is investigated; different boundary conditions are considered