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The ores currently mined have shown increasingly lower grades, impacting on increasing production of tailings and requiring techniques to enable their dry disposal. This study aims to characterize the slump of mineral pastes obtained from slimes thickening, in addition to select the flocculant dosage that presents the best settling answers and the best clarification. The results were obtained by discontinuous settling tests in graduated cylinder with cationic and anionic flocculant, presenting as only operational variable the dosage of flocculant. The clarified liquids obtained in each test had their turbidity determined by digital turbidimeter. To determine the consistency of mineral pastes, slump tests were used in wide concentration range of solids. The results showed that the cationic flocculant had better settling and clarification, whose settling rate and turbidity were, respectively, 2.40 cm/s and 9.4 NTU. For pastes with more than 80% of solids, there was no significant slump, close to 0.3 cm, while diluted slurries had total scattering over the surface. [ABSTRACT FROM AUTHOR]

Abstract: Mutations in the Leucine-rich repeat kinase 2 (LRRK2) gene are known as a common cause of Parkinson''s disease (PD) among patients from different geographic origins. In this study, we evaluated the prevalence of LRRK2 mutations in exons 31 and 41 in a cohort of 154 consecutive, unrelated Brazilian patients with familial or sporadic PD, including early and late onset patients. The LRRK2 p.G2019S mutation was present in heterozygous state in three index cases (∼2%), and in three additional relatives. No carriers of this mutation were found among 250 control chromosomes. Clinically, all mutation-positive patients presented a typical PD phenotype and a good response to levodopa. Mutation segregation analysis in a large sibling showed incomplete penetrance of the p.G2019S. Our findings suggest that the LRRK2 p.G2019S mutation has a substantial contribution to PD susceptibility among Brazilian population and add new clues to current research of this disease. [Copyright &y& Elsevier]