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Vila Velha, Brazil

Bruder A.,Eawag - Swiss Federal Institute of Aquatic Science and Technology | Bruder A.,ETH Zurich | Bruder A.,University of Otago | Schindler M.H.,Eawag - Swiss Federal Institute of Aquatic Science and Technology | And 6 more authors.
Freshwater Biology | Year: 2014

The current rapid decline in biodiversity has led to concerns about the consequences for stream ecosystem processes, one of which is the decomposition of leaf litter derived from riparian vegetation. We conducted field experiments in a tropical and a temperate stream to test for the effects of mixing leaf species differing in resource quality on the decomposition of leaf litter and on the colonisation of the litter by leaf-shredding invertebrates. The effects of litter mixing were minor compared with the effects of litter quality and the presence or absence of shredders. Low shredder abundance in the tropical stream and poor quality of the tropical leaf species, particularly in terms of phosphorus content and toughness, were associated with low decomposition rates in the tropical compared with the temperate stream. This is especially true when considering the 20 °C temperature differences between the two streams. In the presence of shredders, the decomposition rate of a standard litter type, leaves of Alnus glutinosa, was 2.6-fold faster in the temperate stream, whereas rates were similar when shredders were absent. This indicates that differences in environmental conditions other than temperature had a strong effect. Differences in water chemistry, such as higher concentrations of dissolved nutrients in the temperate stream, might account for this effect. In conclusion, despite a lack of clear effects of litter mixing on decomposition, our results highlight the importance of litter identity and environmental conditions for both microbial and shredder-mediated litter decomposition, suggesting that changes in riparian vegetation and other stream characteristics will affect stream ecosystems in the face of widespread environmental change. © 2013 John Wiley & Sons Ltd. Source

Pain is a public health problem responsible for loss of work days. The scope of this article is to analyze the prevalence of dental pain and absenteeism, and the possible association with social and demographic characteristics. This crosssectional study involved a random sample of 169 individuals selected from a universe of 666 workers. Data was collected by a trained researcher using a structured questionnaire. Fisher's Exact Test verified the possible associations; the strength of the associations was verified by the Odds Ratio with 5% significance. The prevalence of dental pain was 46.7%, and absenteeism 12.7%. There was no association between dental pain and the variables analyzed, namely sex, age, income and education. With respect to absenteeism, the individuals with less years of instruction declared greater loss of work hours (OR = 8.850, IC95% = 2.114; 37.046). The prevalence of pain was considerable and was not associated with the controlled variables of this study. Dental pain observed was sufficient to lead to absenteeism, and this was associated with education. Periodic exams must be encouraged for diagnosis and early intervention, thereby minimizing episodes of dental pain. Source

Tonini C.L.,Federal University of Espirito Santo | Campagnaro B.P.,Federal University of Espirito Santo | Louro L.P.S.,Federal University of Espirito Santo | Pereira T.M.C.,Federal Institute of Education | And 3 more authors.
International Journal of Molecular Sciences | Year: 2013

Recent evidence from apolipoprotein E-deficient (apoE-/-) mice shows that aging and atherosclerosis are closely associated with increased oxidative stress and DNA damage in some cells and tissues. However, bone marrow cells, which are physiologically involved in tissue repair have not yet been investigated. In the present study, we evaluated the influence of aging and hypercholesterolemia on oxidative stress, DNA damage and apoptosis in bone marrow cells from young and aged apoE-/- mice compared with age-matched wild-type C57BL/6 (C57) mice, using the comet assay and flow cytometry. The production of both superoxide and hydrogen peroxide in bone marrow cells was higher in young apoE-/- mice than in age-matched C57 mice, and reactive oxygen species were increased in aged C57 and apoE-/- mice. Similar results were observed when we analyzed the DNA damage and apoptosis. Our data showed that both aging and hypercholesterolemia induce the increased production of oxidative stress and consequently DNA damage and apoptosis in bone marrow cells. This study is the first to demonstrate a functionality decrease of the bone marrow, which is a fundamental extra-arterial source of the cells involved in vascular injury repair. © 2013 by the authors; licensee MDPI, Basel, Switzerland. Source

Pena H.F.J.,University of Sao Paulo | Vitaliano S.N.,University of Sao Paulo | Beltrame M.A.V.,University Of Vila Velha | Pereira F.E.L.,Federal University of Espirito Santo | And 2 more authors.
Veterinary Parasitology | Year: 2013

Brazil is one of the regions with the highest prevalences of Toxoplasma gondii in humans and animals. Because free-range chickens become infected by feeding from ground contaminated with oocysts, the prevalence of T. gondii in this host has been widely used as an indicator of the strains prevalent in the environment. The genetic variability among T. gondii isolates from different healthy and sick hosts all over the world has been recently studied. Three clonal genetic lineages (Types I, II and III) were initially recognised as predominant in Western Europe and the United States. T. gondii strains are genetically diverse in South America. In Brazil, recombination plays an important role in strain diversification. The objective of this study was to genetically characterise T. gondii isolates from free-range chickens from Espírito Santo state, Southeast region, Brazil, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). A total of 44 isolates among 47 previously described isolates (TgCkBr234-281) from free-range chickens were included in this study. Strain typing was performed using 12 PCR-RFLP markers: SAG1, SAG2, alt. SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico and CS3. Eleven genotypes were identified. Ten isolates (23%) were grouped into four novel genotypes. Four isolates, distributed in four counties, corresponded to the Type BrI lineage, the genotype found most frequently in Brazil. No clonal Types I, II or III lineages were found. Two novel genotypes were represented by single isolates. Unique alleles were identified for the markers SAG1, c22-8 and CS3, and for the first time, a unique allele was found for the marker SAG3. Although a large number of T. gondii genotypes have already been identified from a variety of animal hosts in Brazil, new genotypes are continuously identified from different animal species. This study confirmed the diversity of T. gondii in Brazil and demonstrates clonal Type I, II and III lineages are rare in this country. © 2012 Elsevier B.V. Source

Camponez M.O.,University Of Vila Velha | Salles E.O.T.,Federal University of Espirito Santo | Sarcinelli-Filho M.,Federal University of Espirito Santo
IEEE Transactions on Image Processing | Year: 2012

Super-resolution (SR) is a technique to enhance the resolution of an image without changing the camera resolution, through using software algorithms. In this context, this paper proposes a fully automatic SR algorithm, using a recent nonparametric Bayesian inference method based on numerical integration, known in the statistical literature as integrated nested Laplace approximation (INLA). By applying such inference method to the SR problem, this paper shows that all the equations needed to implement this technique can be written in closed form. Moreover, the results of several simulations (three of them are here presented) show that the proposed algorithm performs better than other SR algorithms recently proposed. As far as the authors know, this is the first time that the INLA is used in the area of image processing, which is a meaningful contribution of this paper. © 1992-2012 IEEE. Source

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