In multicellular organisms, cell motility is central in all morphogenetic processes, tissue maintenance, wound healing and immune surveillance. Hence, failures in its regulation potentiates numerous diseases. Here, cell migration assays on plastic 2D surfaces were performed using normal (Melan A) and tumoral (B16F10) murine melanocytes in random motility conditions. The trajectories of the centroids of the cell perimeters were tracked through time-lapse microscopy. The statistics of these trajectories was analyzed by building velocity and turn angle distributions, as well as velocity autocorrelations and the scaling of mean-squared displacements. We find that these cells exhibit a crossover from a normal to a super-diffusive motion without angular persistence at long time scales. Moreover, these melanocytes move with non-Gaussian velocity distributions. This major finding indicates that amongst those animal cells supposedly migrating through Lévy walks, some of them can instead perform q-Gaussian walks. Furthermore, our results reveal that B16F10 cells infected by mycoplasmas exhibit essentially the same diffusivity than their healthy counterparts. Finally, a q-Gaussian random walk model was proposed to account for these melanocytic migratory traits. Simulations based on this model correctly describe the crossover to super-diffusivity in the cell migration tracks.

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Environmental issues are often being discussed in society. The Environmental Education implemented in schools appears to be as an important educational tool, which seeks to raise awareness and stimulate the student to look around and feel an integral part of this environment, also contributing to the improvement of the quality of life, as well as the training of citizens aware. The BIOEDUCA project involved 55 students from the 2nd to 5th year of the Municipal School "Rosina Rodrigues Soares Silva" in the municipality of Barão de Cocais - MG. The environmental theme was approached in a dynamic and interactive way with the children, through lectures, group dynamics and practical activities aiming at the knowledge about the preservation of natural resources, the 3Rs and cycles of the materials. The students demonstrated interest and behavior change during the development of the work. The educational action demonstrated effectiveness in the transference of concepts about the environment and sustainability.

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We present an investigation of the mode of road transport in Brazil combining tools of complex networks and real-data. Our analysis involves a data-set based on the service routes inscribed on the Brazilian Transport Agency database. Although connectivity distributions of road networks worldwide are usually claimed as described by a power-law fashion, we report a better fit for the Brazilian case offered by the q-Weibull distribution. In our approach nodes assume the role of localities, whereas links represent service routes among them. Interestingly, a rapid drop takes place on the tail of the data distribution for a particular range of the number of outgoing connections. The mechanism responsible for driving this drop is revealed by investigating the spectral centrality of the network and different patterns of disassortative mixture, for both incoming and outgoing distributions. Besides a discussion about a power law description, we report a contrast with two different distributions. They are interpolated by the q-Weibull one: the Weibull and the q-exponential distributions. Moreover, we study the reciprocity of this network, which reflects the influence of mutual links over dynamical processes. This kind of analysis is indispensable for studies on human mobility, shipping, and a multi-modal perspective.

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Resumo Os danos relacionados à corrosão são frequentes e ocorrem na maioria dos materiais podendo causar grandes prejuízos econômicos. Os aços SAE 1005 modificado e SAE 10B22 são frequentemente usados na produção de fixadores como parafusos e pregos sendo de extrema necessidade a preservação das suas propriedades mecânicas e estruturais nas condições que são aplicados. Neste trabalho foram determinadas as taxas de corrosão destes aços após o contato com soluções aquosas de diferentes concentrações de NaCl e H2SO4 por 45 e 90 dias e comparadas as suas propriedades mecânicas (limite de resistência e alongamento). Os resultados mostraram variação expressiva no alongamento das amostras atacadas por ácido, porém, independente do meio corrosivo, não ocorreram significativas alterações no limite de resistência. As taxas de corrosão das amostras mesmo sendo altas, ainda podem ser consideradas toleráveis. Palavras-chave:Corrosão; Aço baixo carbono; Ensaios mecânicos. COMPARATIVE STUDY OF MECHANICAL PROPERTIES OF SAE 10B22 AND 1005 STEELS AFTER CORROSION IN ELECTROLYTIC SOLUTIONS Abstract Corrosion-related damages are frequent and occur in most materials and can cause great economic damage. SAE 1005 modified and SAE 10B22 steels are often used in the production of fasteners such as bolts and nails and the preservation of their mechanical and structural properties under the conditions that are applied is of extreme necessity. In this work the corrosion rates of these steels were determined after contact with aqueous solutions of different concentrations of NaCl and H2SO4 for 45 and 90 days and compared to their mechanical properties (resistance and elongation limit). The results showed significant variation in the length of the samples attacked by acid, however, regardless of the corrosive medium, there were no significant changes in the resistance limit. The corrosion rates of the samples, even being high, can still be considered tolerable.