32 research outputs found
Electrochemical studies on the corrosion of brass in seawater under anaerobic conditions
This paper reports an electrochemical study on
the corrosion of brass in deoxygenated nonbuffered and
buffered natural and artificial seawater solutions under
anaerobic conditions. Cyclic voltammograms of brass and
copper in natural seawater (NSW) and artificial seawater
(ASW) were obtained in the passive and transpassive
potential regions. The corrosion resistance of brass in
natural and artificial seawater was evaluated, and opencircuit
potentials were recorded over exposure period of
1 week. Brass samples from 3-month exposures in
deoxygenated nonbuffered ASW and NSW, under opencircuit
potential, have been imaged by scanning electron
microscopy, and the elemental composition of the corrosion
products was obtained by energy dispersive spectrometry
analysis. It has been concluded that, under anaerobic
conditions, the aggressivity of NSW is higher, with brass
being less resistant to corrosion than copper, and that buffer
contributes to reduce the aggressivity of both medi
Corrosion of brass in a natural and artificial seawater under anaerobic conditions
The corrosion of brass in deoxygenated nonbuffered
and buffered artificial and natural seawater was
studied. The weight gains and the average corrosion rates
of brass samples, immersed in both media during periods of
1 week, 1 and 3 months, were determined.
The morphology of the corroded surfaces, with and
without the corrosion products, was analyzed by visual
observation and scanning electron microscopy (SEM).
Energy dispersive spectroscopy (EDS) was used for the
identification of the corrosion products and X-ray diffraction
(XRD) for the identification of the crystalline
corrosion products.
In general it was concluded that deoxygenating and
buffering, at pH 9, both contribute to enhance the corrosion
of brass in seawate
Outbreak of Tinea capitis by Trichophyton tonsurans and Microsporum canis in Niterói, RJ, Brazil
18 girls from an orphanage (Orfanato Santo Antônio) in Niterói presented tinea capitis due to Trichophyton tonsurans (15 cases - 83.3%) and Microsporum canis (3 cases - 26.7%). Comments are made about clinical, mycological and therapeutic aspects of this microepidem
Physical activity attenuates the influence of FTO variants on obesity risk: A meta-analysis of 218,166 adults and 19,268 children
Background: The FTO gene harbors the strongest known susceptibility locus for obesity. While many individual studies have suggested that physical activity (PA) may attenuate the effect of FTO on obesity risk, other studies have not been able to confirm this interaction. To confirm or refute unambiguously whether PA attenuates the association of FTO with obesity risk, we meta-analyzed data from 45 studies of adults (n = 218,166) and nine studies of children and adolescents (n = 19,268). Methods and Findings: All studies identified to have data on the FTO rs9939609 variant (or any proxy [r2>0.8]) and PA were invited to participate, regardless of ethnicity or age of the participants. PA was standardized by categorizing it into a dichotomous variable (physically inactive versus active) in each study. Overall, 25% of adults and 13% of children were categorized as inactive. Interaction analyses were performed within each study by including the FTO×PA interaction term in an additive model, adjusting for age and sex. Subsequently, random effects meta-analysis was used to pool the interaction terms. In adults, the minor (A-) allele of rs9939609 increased the odds of obesity by 1.23-fold/allele (95% CI 1.20-1.26), but PA attenuated this effect (pinteraction= 0.001). More specifically, the minor allele of rs9939609 increased the odds of obesity less in the physically active group (odds ratio = 1.22/allele, 95% CI 1.19-1.25) than in the inactive group (odds ratio = 1.30/allele, 95% CI 1.24-1.36). No such interaction was found in children and adolescents. Concl
Novel Loci for Adiponectin Levels and Their Influence on Type 2 Diabetes and Metabolic Traits : A Multi-Ethnic Meta-Analysis of 45,891 Individuals
J. Kaprio, S. Ripatti ja M.-L. Lokki työryhmien jäseniä.Peer reviewe