7,574 research outputs found

    Functional centrality in graphs

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    In this paper we introduce the functional centrality as a generalization of the subgraph centrality. We propose a general method for characterizing nodes in the graph according to the number of closed walks starting and ending at the node. Closed walks are appropriately weighted according to the topological features that we need to measure

    Classification of finite dimensional uniserial representations of conformal Galilei algebras

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    With the aid of the 6j6j-symbol, we classify all uniserial modules of sl(2)hn\mathfrak{sl}(2)\ltimes \mathfrak{h}_{n}, where hn\mathfrak{h}_{n} is the Heisenberg Lie algebra of dimension 2n+12n+1.Comment: Some references added, introduction expanded, title change

    Violence and tactics in the processes of women's integration into copper mining in Chile

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    Indexación: Scopus.El presente artículo busca comprender la experiencia de integración de las mujeres a la Gran minería del cobre en Chile. Para ello, analizamos ocho relatos de vida de trabajadoras de la División Chuquicamata de la empresa estatal Codelco. Se propone que la experiencia de las trabajadoras se estructura entre la violencia ética que sufren y las tácticas que utilizan para responder a ésta. Esta situación genera una paradoja: por una parte, las mujeres cuestionan la segregación de la que han sido históricamente víctimas esforzándose por trabajar a la par de un hombre y, por otra parte, sienten que este esfuerzo amenaza su “femineidad” ante lo cual refuerzan los estereotipos con los cuales se justifica su segregación.ABSTRACT This paper attempts to understand the women’s integration experience to the great copper mining in Chile. In doing so, we analyzed eight life stories of female workers from the Chuquicamata Division of the State-owned company Codelco. We argue that the experience of women workersis structured between the ethical violence they suffer and the tactics they use to face it. This situation lead us to a paradox: one the one hand, women question the segregation of which they have been historically victims, striving to work alongside a man, and on the other hand, they feel that this effort threatens their femininity, reinforcing the stereotypes that justifies their segregationhttp://www.psicoperspectivas.cl/index.php/psicoperspectivas/article/view/101

    A note on a modification of Moser's method

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    We use a recurrence technique to obtain semilocal convergence results for Ulm's iterative method to approximate a solution of a nonlinear equation F (x) = 0fenced((x n + 1 = x n - B n F (x n),, n 0,; B n + 1 = 2 B n - B n F (x n + 1) B n,, n 0 .))This method does not contain inverse operators in its expression and we prove it converges with the Newton rate. We also use this method to approximate a solution of integral equations of Fredholm-type. © 2007 Elsevier Inc. All rights reserved

    A note on Verhulst's logistic equation and related logistic maps

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    We consider the Verhulst logistic equation and a couple of forms of the corresponding logistic maps. For the case of the logistic equation we show that using the general Riccati solution only changes the initial conditions of the equation. Next, we consider two forms of corresponding logistic maps reporting the following results. For the map x_{n+1} = rx_n(1 - x_n) we propose a new way to write the solution for r = -2 which allows better precision of the iterative terms, while for the map x_{n+1}-x_n = rx_n(1 - x_{n+1}) we show that it behaves identically to the logistic equation from the standpoint of the general Riccati solution, which is also provided herein for any value of the parameter r.Comment: 6 pages, 3 figures, 7 references with title

    Schizotypy, Alexithymia and Affect as predictors of Facial Emotion Recognition Capability using static and dynamic images

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    The main purpose of the present study is to investigate the capacity of schizotypy and alexithymia traits, in combination with affectivity to predict facial emotion recognition capability in a sample of nonclinical adults. Consecutive healthy participants (N= 98) were investigated using the Toronto Alexithymia Scale-20 (TAS-20), the Oxford-Liverpool Inventory of Feelings and Experiences-Reduced Version (O-LIFE-R), and the Positive and NA Schedule (PANAS). A set of validated photographs (static images) and virtual faces (dynamic images) for presenting the basic emotions was used to assess emotion recognition. Pearson correlations were applied to investigate the relationship between the study variables; the amount of variance in emotion recognition capability predicted by OLIFE-R, TAS-20 and PANAS was calculated by using the linear regression model. Results showed that alexithymia was strongly associated with schizotypy and NA; furthermore, alexithymia and NA made a significant contribution to the prediction of emotion recognition capability. The predictive model was fitted for two types of presentations (photographs and virtual reality). The inclusion of virtual faces emerges as a response to the need to consider computer characters as new assessment and treatment material for research and therapy in psychologyEl objetivo principal del presente estudio es investigar la capacidad de predicción de los rasgos de esquizotípia y alexitímia, en combinación con la afectividad, de la habilidad de reconocimiento de emociones en una muestra de adultos sanos. Noventa y ocho pacientes sanos (N =98) fueron evaluados mediante la Escala de Alexitímia Toronto-20 (TAS-20), el Inventario de Sentimientos y Experiencias Oxford-Liverpool-Versión Reducida (O-LIFE-R), y la Escala de Afecto Positivo y Negativo (PANAS). Para la evaluación de la capacidad de reconocimiento de emociones a nivel facial, se utilizó un set validado de fotografías (imágenes estáticas) y caras en realidad virtual (imágenes dinámicas). Para el análisis correlacional de las variables de estudio se aplicó la prueba de correlación de Pearson; para el análisis de predicción de la capacidad de reconocimiento emocional se utilizó un modelo de regresión lineal en el que se incluyeron las variables derivadas de las escalas OLIFE-R, TAS-20 y PANAS. Los resultados mostraron la existencia de una relación significativa entre alexitímia, esquizotípia y afecto negativo; el modelo de regresión reveló una aportación significativa de la alexitímia y el afecto negativo en la predicción de los errores cometidos en la tarea de reconocimiento facial. El modelo predictivo propuesto fue válido para ambos tipos de presentación de las emociones (fotografías y caras virtuales). La inclusión de las caras virtuales surge como respuesta a la necesidad de considerar los personajes computarizados como nuevo material de evaluación y tratamiento para la investigación y psicoterapia en psicología

    Schizotypy, Alexithymia and Affect as predictors of Facial Emotion Recognition Capability using static and dynamic images

    Get PDF
    The main purpose of the present study is to investigate the capacity of schizotypy and alexithymia traits, in combination with affectivity to predict facial emotion recognition capability in a sample of nonclinical adults. Consecutive healthy participants (N= 98) were investigated using the Toronto Alexithymia Scale-20 (TAS-20), the Oxford-Liverpool Inventory of Feelings and Experiences-Reduced Version (O-LIFE-R), and the Positive and NA Schedule (PANAS). A set of validated photographs (static images) and virtual faces (dynamic images) for presenting the basic emotions was used to assess emotion recognition. Pearson correlations were applied to investigate the relationship between the study variables; the amount of variance in emotion recognition capability predicted by OLIFE-R, TAS-20 and PANAS was calculated by using the linear regression model. Results showed that alexithymia was strongly associated with schizotypy and NA; furthermore, alexithymia and NA made a significant contribution to the prediction of emotion recognition capability. The predictive model was fitted for two types of presentations (photographs and virtual reality). The inclusion of virtual faces emerges as a response to the need to consider computer characters as new assessment and treatment material for research and therapy in psychologyEl objetivo principal del presente estudio es investigar la capacidad de predicción de los rasgos de esquizotípia y alexitímia, en combinación con la afectividad, de la habilidad de reconocimiento de emociones en una muestra de adultos sanos. Noventa y ocho pacientes sanos (N =98) fueron evaluados mediante la Escala de Alexitímia Toronto-20 (TAS-20), el Inventario de Sentimientos y Experiencias Oxford-Liverpool-Versión Reducida (O-LIFE-R), y la Escala de Afecto Positivo y Negativo (PANAS). Para la evaluación de la capacidad de reconocimiento de emociones a nivel facial, se utilizó un set validado de fotografías (imágenes estáticas) y caras en realidad virtual (imágenes dinámicas). Para el análisis correlacional de las variables de estudio se aplicó la prueba de correlación de Pearson; para el análisis de predicción de la capacidad de reconocimiento emocional se utilizó un modelo de regresión lineal en el que se incluyeron las variables derivadas de las escalas OLIFE-R, TAS-20 y PANAS. Los resultados mostraron la existencia de una relación significativa entre alexitímia, esquizotípia y afecto negativo; el modelo de regresión reveló una aportación significativa de la alexitímia y el afecto negativo en la predicción de los errores cometidos en la tarea de reconocimiento facial. El modelo predictivo propuesto fue válido para ambos tipos de presentación de las emociones (fotografías y caras virtuales). La inclusión de las caras virtuales surge como respuesta a la necesidad de considerar los personajes computarizados como nuevo material de evaluación y tratamiento para la investigación y psicoterapia en psicología

    Stability of conductance oscillations in monatomic sodium wires

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    We study the stability of conductance oscillations in monatomic sodium wires with respect to structural variations. The geometry, the electronic structure and the electronic potential of sodium wires suspended between two sodium electrodes are obtained from self-consistent density functional theory calculations. The conductance is calculated within the framework of the Landauer-B\"utttiker formalism, using the mode-matching technique as formulated recently in a real-space finite-difference scheme [Phys. Rev. B \textbf{70}, 195402 (2004)]. We find a regular even-odd conductance oscillation as a function of the wire length, where wires comprising an odd number of atoms have a conductance close to the quantum unit G0=e2/πG_0=e^2/\pi\hbar, and even-numbered wires have a lower conductance. The conductance of odd-numbered wires is stable with respect to geometry changes in the wire or in the contacts between the wire and the electrodes; the conductance of even-numbered wires is more sensitive. Geometry changes affect the spacing and widths of the wire resonances. In the case of odd-numbered wires the transmission is on-resonance, and hardly affected by the resonance shapes, whereas for even-numbered wires the transmission is off-resonance and sensitive to the resonance shapes. Predicting the amplitude of the conductance oscillation requires a first-principles calculation based upon a realistic structure of the wire and the leads. A simple tight-binding model is introduced to clarify these results.Comment: 16 pages, 20 figure
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