The role of irrigated areas for the spread of schistosomiasis is of worldwide concern. The aim of the present study was to investigate the spatial distribution of the intermediate snail host Biomphalaria in an area highly endemic for schistosomiasis due to Schistosoma mansoni, evaluating the relationship between irrigation and types of natural water sources on one hand, and the influence of place and time of water exposure on the intensity of human infection on the other. A geographical information system (GIS) was used to map the distribution of the intermediate snail hosts in Ilha das Flores, Sergipe, Brazil, combined with a clinical/epidemiological survey. We observed a direct correlation between the intensity of human infection with S. mansoni and irrigation projects. Malacological studies to identify snail species and infection rates showed that B. glabrata is the main species responsible for human schistosomiasis in the municipality, but that B. straminea also plays a role. Our results provide evidence for a competitive selection between the two snail species in rice fields with a predominance of B. glabrata in irrigation systems and B. straminea in natural water sources.

A obra intitulada "Engenharias em foco vol.5", publicada pela Brazilian Journals Publicações de Periódicos e Editora, apresenta um conjunto de quinze capítulos que visa abordar conhecimentos disciplinares ligadas à área temática das Engenharias. A seguir serão apresentados os capítulos que compõem este ebook. Dessa forma, agradecemos aos autores por todo esforço e dedicação que contribuíram para a construção dessa obra, e esperamos que este livro possa colaborar para a discussão e entendimento de temas relevantes para grande área da Engenharia, orientando docentes, estudantes, gestores e pesquisadores à reflexão sobre os assuntos aqui apresentados.

The current work provides kinetic analysis and new equations in adsorption equilibrium process of phenanthrene and pyrene with diffusion model in order to solve partial differential equations problem that integrates the phenomenon of external diffusion mass transfer in the intraparticle layer. The methods are based on the form of solutions and appropriate hypotheses to establish as equations of adsorbed quantity and concentration at the surface of the adsorbed particle. Two unknown functions were evaluated, one related to the concentration function in the liquid (CL) and the other S(t)ϕ(t) the amount adsorbed in time. The parameters E1, 1, E2, 2, were first determined when two sets of experimental data were applied, in which the subscript index 1 represents the modified zeolite adsorbent and the index 2 represents the sepiolite adsorbent. Next, the proposed equations were evaluated by the statistical indicators, which showed the goodness-of-fit. Especially, zeolite has more suitable indicators value. Based on the evaluated equations, the mass transfer coefficients ke1, De1, ke2, De2 are determined respectively in order to obtain a dimensionless Biot number. As a result, modified Zeolite adsorbent presents the best adsorption quality in comparison with Sepiolita. The limiting step determined by Biot in the end highlights the diffusion in the pores in the case of zeolite and external diffusion in the boundary layer in the sepiolite.