Dengue infection plays a central role in our society, since it is the most prevalent vector-borne viral disease affecting humans. We statistically investigated patterns concerning the spatial spreading of dengue epidemics in Brazil, as well as their temporal evolution in all Brazilian municipalities for a period of 12 years. We showed that the distributions of cases in municipalities follow power laws persistent in time and that the infection scales linearly with the population of the municipalities. We also found that the average number of dengue cases does not have a clear dependence on the longitudinal position of municipalities. On the other hand, we found that the average distribution of cases varies with the latitudinal position of municipalities, displaying an almost constant growth from high latitudes until reaching the Tropic of Capricorn leveling to a plateau closer to the Equator. We also characterized the spatial correlation of the number of dengue cases between pairs of municipalities, where our results showed that the spatial correlation function decays with the increase of distance between municipalities, following a power-law with an exponential cut-off. This regime leads to a typical dengue traveling distance. Finally, we considered modeling this last behaviour within the framework of a Edwards-Wilkinson equation with a fractional derivative on space.

We study relaxation patterns of violent conflicts after bursts of activity. Data were obtained from available catalogs on the conflicts in Iraq, Afghanistan and Northern Ireland. We find several examples in each catalog for which the observed relaxation curves can be well described by an asymptotic powerlaw decay (the analog of the Omori's law in geophysics). The power-law exponents are robust, nearly independent of the conflict. We also discuss the exogenous or endogenous nature of the shocks. Our results suggest that violent conflicts share with earthquakes and other natural and social phenomena a common feature in the dynamics of aftershocks.

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h i g h l i g h t s• Statistical analysis of the reaction times in a psychomotor experiment.• Very prolonged blocks of trials without rest breaks. • Performance fitness, persistent behavior and universal patterns. a b s t r a c tIn this study, we analyze the reaction times obtained from participants in a psychomotor activity composed of a large number of trials without breaks. We numerically evaluate the learning factor directly obtained as the interevent time in the subsequent trials comparing two different blocks of trials. We investigate the learning in terms of average values and their respective variability. In a broader scenario, we show that the learning can be associated with a scale factor acting over the reaction times. Aside from the fitness improvement, we identify that the reaction times have a positively skewed distribution, while their differences are distributed symmetrically as a Laplace distribution whose width diminishes with practice. We found that the differences of the reaction times after practicing become smaller obeying a linear rule. In addition to these universal patterns, we verify that the performance fitness does not exhibit persistence, but their differences do exhibit persistent behavior on the absolute values and anti-persistent behavior for the signs.

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