Indios, Moradores e Câmaras Municipais : Etnicidade e conflitos agrários no Rio de Janerio e no Espírito Santo (séculos XVIII e XIX)

This paper analyzes the processes of extinction of indigenous collective lands and villages in Rio de Janeiro and Espírito Santo, from mid-eighteenth century to the nineteenth century, giving emphasis on the role of IndigenousÆs policy aiming to delay the process. Based on the correspondence among authorities, laws, statistical reports, and petitions from the Indians themselves, we approach the agrarian conflicts among indigenous, non-Indian residents and municipal councils, focusing on the issue of controversies and discussions regarding ethnicity that played a central role in these disputes.

Educación del cuerpo, escolarización y modernidad : Apuntamientos sueltos

A partir de la catalogación del material conservado en el Departamento Estadual de Arquivo Público - DEAP, buscamos comprender cómo se pensaba la educación del cuerpo en la escuela primaria, en el Estado de Paraná, en el período comprendido entre 1882 y 1920. Nuestra búsqueda se centró en la Coleção Correspondência de Governo ÔöÇ un conjunto de 2379 volúmenes encuadernados (APs). El foco principal del análisis fue el contenido de los relatorios producidos por diferentes agentes escolares. Muchos de esos registros remiten a una dimensión de la escolarización que denominamos educación del cuerpo. Para su efectuación contribuyeron dispositivos tan diversificados como la organización del tiempo y del espacio escolares, la construcción del currículo, la coeducación, entre otros. Así, fuimos conducidos por la necesidad de comprender las relaciones entre modernidad, corporalidad y escolarización. Para eso establecimos un diálogo con una historiografía que contempla trabajos de Thompson, 1981; Ginzburg, 1989; Ragazzini, 2001; Faria Filho, 2000; Souza, 1998; Vago, 2002; Viñao,1990; Aisenstein, 1999., entre otros. Dedicar atención a las tensiones entre discursos, formulaciones legales y prácticas escolares centradas en la corporalidad, representa una clave de entendimiento del proceso de escolarización rica en posibilidades. Al dialogar con las fuentes catalogadas, queda clara la preocupación de los agentes escolares con relación a la importancia de la escuela, en particular para la dimensión de la educación corporal o physica. Así que elaboramos una interpretación que comprende la corporalidad como punto central del modelo escolar graduado, que sería el locus de definición de estrategias que educaban el cuerpo para la construcción de una sociedad más "civilizada".

Indios, Moradores e Câmaras Municipais : Etnicidade e conflitos agrários no Rio de Janerio e no Espírito Santo (séculos XVIII e XIX)

This paper analyzes the processes of extinction of indigenous collective lands and villages in Rio de Janeiro and Espírito Santo, from mid-eighteenth century to the nineteenth century, giving emphasis on the role of IndigenousÆs policy aiming to delay the process. Based on the correspondence among authorities, laws, statistical reports, and petitions from the Indians themselves, we approach the agrarian conflicts among indigenous, non-Indian residents and municipal councils, focusing on the issue of controversies and discussions regarding ethnicity that played a central role in these disputes.

Analytical properties of horizontal visibility graphs in the Feigenbaum scenario

Time series are proficiently converted into graphs via the horizontal visibility (HV) algorithm, which prompts interest in its capability for capturing the nature of different classes of series in a network context. We have recently shown [B. Luque et al., PLoS ONE 6, 9 (2011)] that dynamical systems can be studied from a novel perspective via the use of this method. Specifically, the period-doubling and band-splitting attractor cascades that characterize unimodal maps transform into families of graphs that turn out to be independent of map nonlinearity or other particulars. Here, we provide an in depth description of the HV treatment of the Feigenbaum scenario, together with analytical derivations that relate to the degree distributions, mean distances, clustering coefficients, etc., associated to the bifurcation cascades and their accumulation points. We describe how the resultant families of graphs can be framed into a renormalization group scheme in which fixed-point graphs reveal their scaling properties. These fixed points are then re-derived from an entropy optimization process defined for the graph sets, confirming a suggested connection between renormalization group and entropy optimization. Finally, we provide analytical and numerical results for the graph entropy and show that it emulates the Lyapunov exponent of the map independently of its sign.

Time series irreversibility: a visibility graph approach

We propose a method to measure real-valued time series irreversibility which combines two different tools: the horizontal visibility algorithm and the Kullback-Leibler divergence. This method maps a time series to a directed network according to a geometric criterion. The degree of irreversibility of the series is then estimated by the Kullback-Leibler divergence (i.e. the distinguishability) between the in and out degree distributions of the associated graph. The method is computationally efficient and does not require any ad hoc symbolization process. We find that the method correctly distinguishes between reversible and irreversible stationary time series, including analytical and numerical studies of its performance for: (i) reversible stochastic processes (uncorrelated and Gaussian linearly correlated), (ii) irreversible stochastic processes (a discrete flashing ratchet in an asymmetric potential), (iii) reversible (conservative) and irreversible (dissipative) chaotic maps, and (iv) dissipative chaotic maps in the presence of noise. Two alternative graph functionals, the degree and the degree-degree distributions, can be used as the Kullback-Leibler divergence argument. The former is simpler and more intuitive and can be used as a benchmark, but in the case of an irreversible process with null net current, the degree-degree distribution has to be considered to identify the irreversible nature of the series

Phase transition in the countdown problem

We present a combinatorial decision problem, inspired by the celebrated quiz show called Countdown, that involves the computation of a given target number T from a set of k randomly chosen integers along with a set of arithmetic operations. We find that the probability of winning the game evidences a threshold phenomenon that can be understood in the terms of an algorithmic phase transition as a function of the set size k. Numerical simulations show that such probability sharply transitions from zero to one at some critical value of the control parameter, hence separating the algorithm's parameter space in different phases. We also find that the system is maximally efficient close to the critical point. We derive analytical expressions that match the numerical results for finite size and permit us to extrapolate the behavior in the thermodynamic limit.