BACKGROUND The National Socioeconomic Characterization Survey (CASEN) was modified in the year 2000, to include an assessment of the inequalities in the access to health services. AIM To analyze the health issues of year 2000 survey database. MATERIAL AND METHODS During 2000, 38338 urban and 26698 rural dwellings were surveyed, totaling 240000 people analyzing ascription to public or privat...

The ability of Gaussian noise to induce ordered states in dynamical systems is here presented in an overview of the main stochastic mechanisms able to generate spatial patterns. These mechanisms involve: (i) a deterministic local dynamics term, accounting for the local rate of variation of the field variable, (ii) a noise component (additive or multiplicative) accounting for the unavoidable env...

Localized ecological interactions can generate striking large-scale spatial patterns in ecosystems through spatial self-organization. Possible mechanisms include oscillating consumer-resource interactions, localized disturbance-recovery processes and scale-dependent feedback. Despite abundant theoretical literature, studies revealing spatial self-organization in real ecosystems are limited. Rec...

This paper deals with coexistence issues that may arise for Wireless Body Area Networks (WBANs) operating at the 2.45 GHz ISM band. Two different sources of interference are considered: IEEE 802.11 (Wi-Fi) and IEEE 802.15.4 (Zigbee). Firstly, these interfering networks are characterized both in the frequency and in the time domains. Then, the coexistence of a WBAN with these interfering systems...

We present a Shack-Hartmann (SH) centroid detection algorithm capable to measure in presence of strong noise, background illumination and spot modulating signals, which are typical limiting factors of traditional centroid detection algorithms. The proposed method is based on performing a normalization of the SH pattern using the spiral phase transform method and Fourier filtering. The spot cent...

Predation risk is often associated with group formation in prey, but recent advances in methods for analysing the social structure of animal societies make it possible to quantify the effects of risk on the complex dynamics of spatial and temporal organisation. In this paper we use social network analysis to investigate the impact of variation in predation risk on the social structure of guppy ...