Epidemic spreading on interconnected networks

Many real networks are not isolated from each other but form networks of networks, often interrelated in non trivial ways. Here, we analyze an epidemic spreading process taking place on top of two interconnected complex networks. We develop a heterogeneous mean field approach that allows us to calculate the conditions for the emergence of an endemic state. Interestingly, a global endemic state may arise in the coupled system even though the epidemics is not able to propagate on each network separately, and even when the number of coupling connections is small. Our analytic results are successfully confronted against large-scale numerical simulations

Urban destination loyalty drivers and cross-national moderator effects: The case of Barcelona

The objective of this paper is to analyze the loyalty of tourists to urban tourism destinations, studying the differences existing on the basis of nationality of origin. The review of the academic literature identified perceived value and satisfaction as antecedents of loyalty. A theoretical model was constructed which was tested empirically with a total of 927 surveys of Italian and American tourists in the city of Barcelona. In the study of the data, structural equation models (SEM) were used, by means of a multi-group analysis. The empirical results show that the causal relationships among perceived value, satisfaction and loyalty and the moderating effect of nationality are partially confirmed. This study contributes to better knowledge of the processes that lead tourists to be loyal to an urban tourism destination

Análisis de resultados métricos de una nube de puntos y una medición directa en el patrimonio edificado. El Santuario de La Montaña en Cáceres

This article makes a comparative study of two types of methods used in building construction. On one hand, the creation of drawings uses direct method, basically by measuring and sketching without instruments and, on the other hand, the creation of these plans by modern laser scanning. The aim is to analyze the accuracy of final results and to consider the technical and other resources needed to carry out each method. Two different works, concerning the same building are compared. More specifically works consist of plan views and section views from a project executed and a scanning with laser technology performed of some parts of the same building. From there we will take out the appropriate cross-section slices to get the information needed to make plan and section views. The outcome will be to get information on the level of accuracy and to assess the technical effort required in each case.El objetivo del presente artículo consiste en realizar un estudio comparativo entre dos procedimientos utilizados en el levantamiento de un edificio: método directo sin instrumentación y escaneado láser que proporciona nubes de puntos de gran densidad. Se pretende analizar el grado de exactitud de los resultados y los recursos y medios técnicos precisos para llevar a cabo cada una de las tecnologías. La metodología consistirá en comparar dos trabajos relativos al mismo edificio. Por un lado, se cuenta con unos planos de planta y sección de un proyecto orientado a la rehabilitación del edificio. Por otra parte, se utiliza un escaneado con tecnología láser, del que se tomará una selección de puntos precisa para obtener la información necesaria para poder realizar los planos de planta y sección, equivalentes a los anteriores. El resultado consistirá en tener una información del grado de exactitud de cada método, valorando el esfuerzo técnico que requiere cada uno de ellos

Discursos pronunciados al asumir el arquitecto Joaquín J. Rodríguez Saumell la Presidencia de la Universidad Nacional de la Plata el 26 de Setiembre de 1967

Discursos pronunciados por el Doctor Santiago Gorostiague, Presidente saliente de la Universidad, el Doctor José Mariano Astigueta, Secretario de Estado de Cultura y Educación de la Nación y el arquitecto Joaquín J. Rodríguez Saumell, nuevo presidente de la Universidad en el acto de asunción de éste último en el año 1966.Material digitalizado en SEDICI gracias a la Biblioteca de la Facultad de Ingeniería (UNLP).Universidad Nacional de La Plat

Discursos pronunciados al asumir el arquitecto Joaquín J. Rodríguez Saumell la Presidencia de la Universidad Nacional de la Plata el 26 de Setiembre de 1967

Discursos pronunciados por el Doctor Santiago Gorostiague, Presidente saliente de la Universidad, el Doctor José Mariano Astigueta, Secretario de Estado de Cultura y Educación de la Nación y el arquitecto Joaquín J. Rodríguez Saumell, nuevo presidente de la Universidad en el acto de asunción de éste último en el año 1966.Material digitalizado en SEDICI gracias a la Biblioteca de la Facultad de Ingeniería (UNLP).Universidad Nacional de La Plat

Discursos pronunciados al asumir el arquitecto Joaquín J. Rodríguez Saumell la Presidencia de la Universidad Nacional de la Plata el 26 de Setiembre de 1967

Discursos pronunciados por el Doctor Santiago Gorostiague, Presidente saliente de la Universidad, el Doctor José Mariano Astigueta, Secretario de Estado de Cultura y Educación de la Nación y el arquitecto Joaquín J. Rodríguez Saumell, nuevo presidente de la Universidad en el acto de asunción de éste último en el año 1966.Material digitalizado en SEDICI gracias a la Biblioteca de la Facultad de Ingeniería (UNLP).Universidad Nacional de La Plat

A continuous rating method for preferential voting. The complete case

A method is given for quantitatively rating the social acceptance of different options which are the matter of a complete preferential vote. Completeness means that every voter expresses a comparison (a preference or a tie) about each pair of options. The proposed method is proved to have certain desirable properties, which include: the continuity of the rates with respect to the data, a decomposition property that characterizes certain situations opposite to a tie, the Condorcet-Smith principle, and a property of clone consistency. One can view this rating method as a complement for the ranking method introduced in 1997 by Markus Schulze. It is also related to certain methods of one-dimensional scaling or cluster analysis.Comment: This is part one of a revised version of arxiv:0810.2263. Version 3 is the result of certain modifications, both in the statement of the problem and in the concluding remarks, that enhance the results of the paper; the results themselves remain unchange

In vitro anthelmintic effect of plant extracts against infective larvae of ruminants gastrointestinal nematode parasites

With the purpose of studying the anthelmintic efficacy of some plant species presents in Queensland State, Australia, we tested in vitro the effect of plant extracts on infective larvae (L3) migration of Haemonchus placei, Cooperia sp., Haemonchus contortus and Trichostrongylus colubriformis. In general, plant extracts reduced the larval migration of Haemonchus placei and Cooperia sp. The most effective plants against Haemonchus placei and Cooperia sp. (P < 0.0001) were Allocasuarina torulosa, Neolitsea dealbata, Acacia holosericea, Acacia salicina, Callitris endlicheri and Casuarina cunninghamiana. Plants extracts were less effective on L3 migration of Haemonchus contortus and Trichostrongylus colubriformis. Callitris endlicheri, Casuarina cunninghamiana, Acacia farnesiana, Acacia holosericea and Acacia nilotica were the plant extracts that shown an important larval migration inhibition against H. contortus and Trichostrongylus colubriformis (P < 0.0001). Callitris endlicheri was the plant that consistently inhibited the larval migration of every nematode species under study. These in vitro results suggest anthelmintic properties associate with some of the plant species we studied.EEA Cerro AzulFil: Moreno, Fabiana Carina. University Drive. CSIRO Davies Laboratory; Australia. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad Ciencias Veterinarias; Argentina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Montecarlo; ArgentinaFil: Gordon, Iain J. University Drive. CSIRO Davies Laboratory; AustraliaFil: Wright, A.D. AIMS Australian Institute of Marine Science; AustraliaFil: Benvenutti, Marcelo. University Drive. CSIRO Davies Laboratory; Australia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Montecarlo; ArgentinaFil: Saumell, Carlos A. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad Ciencias Veterinarias; Argentin

Epidemics in partially overlapped multiplex networks

Many real networks exhibit a layered structure in which links in each layer reflect the function of nodes on different environments. These multiple types of links are usually represented by a multiplex network in which each layer has a different topology. In real-world networks, however, not all nodes are present on every layer. To generate a more realistic scenario, we use a generalized multiplex network and assume that only a fraction $q$ of the nodes are shared by the layers. We develop a theoretical framework for a branching process to describe the spread of an epidemic on these partially overlapped multiplex networks. This allows us to obtain the fraction of infected individuals as a function of the effective probability that the disease will be transmitted $T$. We also theoretically determine the dependence of the epidemic threshold on the fraction $q > 0$ of shared nodes in a system composed of two layers. We find that in the limit of $q \to 0$ the threshold is dominated by the layer with the smaller isolated threshold. Although a system of two completely isolated networks is nearly indistinguishable from a system of two networks that share just a few nodes, we find that the presence of these few shared nodes causes the epidemic threshold of the isolated network with the lower propagating capacity to change discontinuously and to acquire the threshold of the other network.Comment: 13 pages, 4 figure