Phase transition for the frog model

We study a system of simple random walks on graphs, known as frog model. This model can be described as follows: There are active and sleeping particles living on some graph G. Each active particle performs a simple random walk with discrete time and at each moment it may disappear with probability 1-p. When an active particle hits a sleeping particle, the latter becomes active. Phase transition results and asymptotic values for critical parameters are presented for Z^d and regular trees

Digital democracy? No, infocracy! The uses of social media by the Portuguese unions in the health sector

Trade unions are facing a deep crisis since the 70s. The causes are multiple, including factors that are exogenous to the movement and others that are endogenous, referring to its bureaucratization. Aiming to revitalize, they have been implementing several actions, among which we may refer the adoption of ICT and the Internet. This article presents the preliminary results of a research on the adoption and uses of the Internet by the unions in the health sector in Portugal. It aimed to understand if they are allowing or not the deepening of organizational democracy, a crucial factor for the revitalization. We will conclude by stating that, given the static nature and the poor interactivity that characterize the official websites of these unions and the way the social media is used, the unions are losing an opportunity to the deepening of the democratic forms of associative government and therefore to strengthen themselves.info:eu-repo/semantics/acceptedVersio

Generation and detection of bound entanglement

We propose a method for the experimental generation of two different families of bound entangled states of three qubits. Our method is based on the explicit construction of a quantum network that produces a purification of the desired state. We also suggest a route for the experimental detection of bound entanglement, by employing a witness operator plus a test of the positivity of the partial transposes

Human case of West Nile neuroinvasive disease in Portugal, summer 2015

A case of West Nile virus (WNV) infection was reported in the Algarve region, Portugal, in the first week of September 2015. WNV is known to circulate in Portugal, with occasional reports in horses and birds (2004 to 2011) and very sporadically human cases (in 2004 and in 2010). Here we present the clinical and laboratory aspects related to the first human case of West Nile neuroinvasive disease reported in Portugal