Paisajes culturales en cambio bajo el impacto del exilio, las diásporas y el retorno de la emigración

This article discusses the impact of territorial displacement on Argentina, Chile, Paraguay and Uruguay during the cycle of dictatorships and democratization of the late twentieth century and early twenty-first century. It points out the complexities and different forms of exile, expatriation and migration which these societies experienced, while asserting that exile could not be undone fully with democratization, as many of those who left did not come back, others left in new waves of expatriation, and even those who did return could not resume what had been left behind. Yet, the experience of living elsewhere broadened the social, political and cultural perspectives. Whether returning or not, or becoming sojourners, many individuals who left during the dictatorship made substantial contributions to the societies of origin in domains as varied as politics, arts and letter, science, the publishing industry, education, the state apparatus and the economy. Illustrations of such varied impact are presented.Este artículo discute el impacto del desplazamiento territorial en Argentina, Chile, Paraguay y Uruguay durante el ciclo de dictaduras y democratización de finales del siglo XX y principios del siglo XXI. Señala las complejidades y las diferentes formas de exilio, expatriación y migración que vivieron estas sociedades, al tiempo que afirma que el exilio no se pudo superar completamente con la democratización, ya que muchos de los que se marcharon no regresaron, otros se fueron en nuevas olas de expatriación, e incluso aquellos que regresaron no pudieron reanudar lo que se había dejado atrás. Sin embargo, la experiencia de vivir en otro lugar amplió las perspectivas sociales, políticas y culturales. Ya sea que regresaran o no, o mantuvieran una vida ambulante entre el país de origen y el país de residencia, muchos de aquéllos que dejaron el suelo patrio durante la dictadura hicieron en post-dictadura contribuciones sustanciales a las sociedades de origen en dominios tan variados como la política, las artes y las letras, la ciencia, la industria editorial, la educación, el aparato estatal y la economía. El artículo presenta ilustraciones de tal impacto variado en el Cono Sur

Transportation in mega-cities: a local issue, a global question

This repository item contains a single issue of Issues in Brief, a series of policy briefs that began publishing in 2008 by the Boston University Frederick S. Pardee Center for the Study of the Longer-Range Future.This policy brief reviews the looming emergence of ever-more and ever-bigger mega-cities and, within them, the challenge of urban transportation

Ermakov Systems with Multiplicative Noise

Using the Euler-Maruyama numerical method, we present calculations of the Ermakov-Lewis invariant and the dynamic, geometric, and total phases for several cases of stochastic parametric oscillators, including the simplest case of the stochastic harmonic oscillator. The results are compared with the corresponding numerical noiseless cases to evaluate the effect of the noise. Besides, the noiseless cases are analytic and their analytic solutions are briefly presented. The Ermakov-Lewis invariant is not affected by the multiplicative noise in the three particular examples presented in this work, whereas there is a shift effect in the case of the phasesComment: 12 pages, 4 figures, 22 reference

Early Science with the Large Millimeter Telescope: COOL BUDHIES I - a pilot study of molecular and atomic gas at z~0.2

An understanding of the mass build-up in galaxies over time necessitates tracing the evolution of cold gas (molecular and atomic) in galaxies. To that end, we have conducted a pilot study called CO Observations with the LMT of the Blind Ultra-Deep H I Environment Survey (COOL BUDHIES). We have observed 23 galaxies in and around the two clusters Abell 2192 (z = 0.188) and Abell 963 (z = 0.206), where 12 are cluster members and 11 are slightly in the foreground or background, using about 28 total hours on the Redshift Search Receiver (RSR) on the Large Millimeter Telescope (LMT) to measure the $^{12}$CO J = 1 --> 0 emission line and obtain molecular gas masses. These new observations provide a unique opportunity to probe both the molecular and atomic components of galaxies as a function of environment beyond the local Universe. For our sample of 23 galaxies, nine have reliable detections (S/N$\geq$3.6) of the $^{12}$CO line, and another six have marginal detections (2.0 < S/N < 3.6). For the remaining eight targets we can place upper limits on molecular gas masses roughly between $10^9$ and $10^{10} M_\odot$. Comparing our results to other studies of molecular gas, we find that our sample is significantly more abundant in molecular gas overall, when compared to the stellar and the atomic gas component, and our median molecular gas fraction lies about $1\sigma$ above the upper limits of proposed redshift evolution in earlier studies. We discuss possible reasons for this discrepancy, with the most likely conclusion being target selection and Eddington bias.Comment: MNRAS, submitte

Synchronization of interconnected networks: the role of connector nodes

In this Letter we identify the general rules that determine the synchronization properties of interconnected networks. We study analytically, numerically and experimentally how the degree of the nodes through which two networks are connected influences the ability of the whole system to synchronize. We show that connecting the high-degree (low-degree) nodes of each network turns out to be the most (least) effective strategy to achieve synchronization. We find the functional relation between synchronizability and size for a given network-of-networks, and report the existence of the optimal connector link weights for the different interconnection strategies. Finally, we perform an electronic experiment with two coupled star networks and conclude that the analytical results are indeed valid in the presence of noise and parameter mismatches.Comment: Accepted for publication in Physical Review Letters. Main text: 5 pages, 4 figures. Supplemental material: 8 pages, 3 figure

Qubits entanglement dynamics modified by an effective atomic environment

We study entanglement dynamics of a couple of two-level atoms resonantly interacting with a cavity mode and embedded in a dispersive atomic environment. We show that in the absence of the environment the entanglement reaches its maximum value when only one exitation is involved. Then, we find that the atomic environment modifies that entanglement dynamics and induces a typical collapse-revival structure even for an initial one photon Fock state of the field.Comment: eight pages, two figure include

Communal Responsibility and the Coexistence of Money and Credit Under Anonymous Matching

Communal responsibility, a medieval institution studied by Greif (2006), supported the use of credit among European merchants in the absence of modern enforcement technologies. This paper shows how this mechanism helps to overcome enforcement problems in anonymous buyer/seller transactions. In a village economy version of the Lagos and Wright (2005) model, agents trading anonymously in decentralized markets can be identified by their citizenship and thus be held liable for each other. Enforceability within each village's centralized afternoon market ensures collateralization of credit in decentralized markets. In the resulting equilibrium, money and credit coexist in decentralized markets if the use of credit is costly. Our analysis easily extends itself to other payment systems like credit cards that provide a group identity to otherwise anonymous agents.Communal responsibility, anonymous matching, money demand, credit, bills of exchange