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1.
Front Chem ; 8: 272, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351939

RESUMO

The present work focuses on the characterization of brass surfaces after contact with artificial saliva solution at pH 7.4 and phosphate buffer solution at pH 7 simulating two extreme conditions that might occur when playing ancient brass wind instruments in the context of historically informed performance practice. The composition and the morphology of the film formed following the contact with the solutions for 1, 3, and 16 h were investigated by ex situ X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) to shed a light on the surface changes upon time. In situ electrochemical impedance spectroscopy (EIS) was used to study the mechanism of corrosion and protection of the alloys. The results could be interpreted using a reliable equivalent electrical circuit; they provided evidence that the alloys behave differently when in contact to the various solutions. In saliva solution the formation on the brass surface of a thick surface film was observed, composed of crystallites of about 200 nm size mainly composed of CuSCN and Zn3(PO4)2. This layer hinders the alloy dissolution. The contact of the alloys with the buffer solution originated a much thinner layer composed of Cu2O, ZnO, and a small amount of Zn3(PO4)2. This film is rapidly formed and does not evolve upon time in a protective film.

2.
Int J Public Health ; 62(3): 407-414, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28233018

RESUMO

OBJECTIVES: To examine cancer trend using age-period-cohort analysis with a cohort of patients in Sardinia, Italy, where epidemiological transition occurred between 1950 and 1960. METHODS: Poisson log-linear regression models were used to analyze time trend in patients undergoing upper endoscopy between 1995 and 2013. RESULTS: A total of 10,546 clinical records (62.2% women) were retrieved. In 541 patients (5.1%), a diagnosis of cancer was reported, more often in men (5.5%) than in women (4.9%). Age and birth cohort were significantly associated with cancer rate according to age-period-cohort analysis (p < 0.0001), whereas the effect of time period was negligible (p = 0.875). An upward trend for all cancers was observed in the younger generations (7.15% before 1950, 8.85% between 1950 and 1960, and 10.7% after 1960). CONCLUSIONS: Population aging and increased exposure to cancer risk factors after epidemiological transition were the major determinants associated with cancer in this Sardinian cohort, whereas time period had no effect, ruling out any variation in diagnostic accuracy. These results may facilitate the provision of preventive measures by the health care system, and improve population-tailored cancer screening strategies.


Assuntos
Neoplasias/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Socioeconômicos , Fatores de Tempo , Adulto Jovem
3.
Water Sci Technol ; 61(11): 2873-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20489260

RESUMO

The main aim of this work was to know how spread is laccase activity in spores of Bacillus species isolated from a soil where Italian law allows olive mill wastewater (OMW) spreading, and to investigate the potential role of such autochthonous soil microorganisms in degradation of OMW phenols, and prevention of groundwater pollution. Laccase activity was detected for the first time in spores of wild-type Bacillus pumilus, B. cereus sensu lato, and B. amyloliquefaciens strains. Because B. pumilus, B. cereus sensu lato, and B. amyloliquefaciens, together with B. subtilis account for a total of 93% of Bacillus isolates at the study site, the nearly totality of Bacillus spores reveals laccase activity. Thus, taking also into consideration that Bacillus spores are more abundant (about 100-fold) than white-rot fungi (that possess a well known extracellular, radical-based ligninolytic enzyme system capable of degrading OMW phenols) in the studied soil, these spores may contribute to in-situ degradation of OMW phenols. This role is further emphasized by dilution of crude OMW during infiltration of rainwater through soil that allows to minimize the antibacterial activity of phenols. The widespread presence of Bacillus spores in soils indicates a potential detoxifying role of these spores in a broader context.


Assuntos
Bacillus/enzimologia , Olea , Esporos Bacterianos/enzimologia , Proteínas de Bactérias/metabolismo , Resíduos Industriais , Lacase/metabolismo , Fenóis/metabolismo , Microbiologia do Solo , Eliminação de Resíduos Líquidos
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