19 research outputs found

    Quantitative-spatial assessment of soil contamination in S. Francisco de Assis due to mining activity of the Panasqueira mine (Portugal)

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    Through the years, mining and beneficiation processes produces large amounts of As-rich mine wastes laid up in huge tailings and open-air impoundments (Barroca Grande and Rio tailings) that are the main source of pollution in the surrounding area once they are exposed to the weathering conditions leading to the formation of AMD and consequently to the contamination of the surrounding environments, in particularly soils. In order to investigate the environmental contamination impact on S. Francisco de Assis (village located between the two major impoundments and tailings) agricultural soils, a geochemical survey was undertaken to assess toxic metals associations, related levels and their spatial distribution, and to identify the possible contamination sources. According to the calculated contamination factor, As and Zn have a very high contamination factor giving rise to 65.4 % of samples with a moderate to high pollution degree; 34.6 % have been classified as nil to very low pollution degree. The contamination factor spatial distribution put in evidence the fact that As, Cd, Cu, Pb, and Zn soils contents, downstream Barroca Grande tailing, are increased when compared with the local Bk soils. The mechanical dispersion, due to erosion, is the main contamination source. The chemical extraction demonstrates that the trace metals distribution and accumulation in S. Francisco de Assis soils is related to sulfides, but also to amorphous or poorly crystalline iron oxide phases. The partitioning study allowed understanding the local chemical elements mobility and precipitation processes, giving rise to the contamination dispersion model of the study area. The wind and hydrological factors are responsible for the chemical elements transport mechanisms, the water being the main transporter medium and soils as one of the possible retention media

    Aparelho de amplificação sonora individual: melhora a sensação de zumbido? Hearing aid: does it reduce the sensation of tinnitus?

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    OBJETIVO: observar se o uso da amplificação sonora além de garantir melhora na inteligibilidade de fala pode proporcionar alívio na sensação de zumbido. MÉTODOS: participaram do presente estudo 21 indivíduos, usuários de aparelho de amplificação sonora individual (AASI) que referiam sensação de zumbido, além da perda auditiva sensorioneural, sendo 13 (61,9%) indivíduos do sexo feminino e oito (38,1%) do sexo masculino. A idade dos participantes variou entre 35 a 88 anos, com idade média de 61 anos. Para a avaliação dos participantes foi utilizado um questionário específico. Os dados foram analisados por meio de análise estatística descritiva e para tanto foram utilizados os testes não paramétricos: qui-quadrado e Kruskal-Wallis H. RESULTADOS: Entre os 21 participantes, 17 (80,9%) apresentaram melhora do zumbido, enquanto quatro (19,1%) referiram que o aparelho de amplificação não gerou nenhum efeito sobre o sintoma apresentado. CONCLUSÃO: este estudo verificou que a utilização do AASI reduziu imediatamente a sensação de zumbido apresentada na população estudada.<br>PURPOSE: to observe if the use of hearing aid may provide relief in tinnitus sensation besides guarantying the improvement of speech intelligibility. METHODS: a sample was made up by 21 hearing aid users and a specific questionnaire was used for the evaluation of the participants. The ages ranged from 35 to 88-year old, with an average of 61-year old. The tinnitus sensation was mentioned by 13 (61.9%) female beings and eight (38.1%) male beings beyond sensory neural hearing loss. The results were obtained through a descriptive statistical analysis, and furthermore, non-parametric tests were used, such as chi-square and Kruskal-Wallis H. RESULTS: among the participants 17 (80.9%) showed recovery from tinnitus, while four (19.1%) said that the hearing aid device did not cause any effect on the evidenced symptoms. CONCLUSION: this study found out that the usage of the hearing aid reduced promptly the sensation of tinnitus in the studied subjects
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