Marcelo Barbosa de Almeida

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This work reports on the effect of land use change on Hg distribution in Amazon soils. It provides a comparison among Hg concentrations and distribution along soil profiles under different land use categories; primary tropical forest, slashed forest prior to burning, a 1-year silviculture plot planted after 4 years of forest removal and a 5-year-old pasture(More)
Changes in hydrochemistry and Hg distribution in the Madeira River from Porto Velho to the confluence with the Amazon River were studied in two cruises in 1997 and 2002. Water conductivity was similar in both periods, but the pH was significantly higher in 2002, in particular along the middle reaches of the river. Total suspended matter concentrations also(More)
A Teflon dynamic flux chamber was used to characterize Gaseous Elemental Mercury (GEM) flux from forested and open field soils in a highly changing environment in Rondônia State, western Amazon. We simultaneously analyzed meteorological parameters at the soil level relating GEM fluxes to soil temperature, air humidity, soil moisture, solar radiation, and(More)
Este estudo descreve as mudanças na especiação de Hg nas águas da Baía de Sepetiba, SE, Brasil, ao longo do gradiente estuarino, durante eventos de maré em diferentes estações. A avaliação química das águas da baía indicou uma exportação de material particulado em suspensão (MPS) pobre em carbono orgânico para a plataforma continental adjacente,(More)
Parametric rolling is a major issue affecting nowadays modern fishing and containership fleets. This sudden phenomenon implies huge rolling oscillations that can cause cargo damage, crew injuries and may lead to the loss of the vessel in the most severe cases. Due to its short development time and the nonlinear behaviour of parametric rolling, a real time(More)
Background: There is a lack of studies on the occurrence of spontaneous conduction disturbances at atrial level in small animals. Bachmann ́s bundle block is a particular type of interatrial cardiac conduction disturbance that is characterized by a variable delay on electrical depolarization of both atria resulting in prolonged P waves duration on the(More)
Objetivo: Avaliar a eficácia do colírio de concentrado de plaquetas (CCP) autólogo no olho seco sintomático de pacientes diabéticos. Projeto: Um estudo de intervenção único grupo prospectivo. Participantes: Doze pacientes diabéticos com doença do olho seco refratário. Métodos: Os pacientes foram tratados com colírio de PRP autólogo quatro vezes por dia(More)
The aim of the research was to study the frequency of reading and physical activity in elderly people. The participants were divided in four groups according to the following issues: gender and social success in their community; each group was composed by 10 people, at the age of 70 or more. The instruments used to collect data were: an agreement term, a(More)
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