1000 resultados para SOUTHERN BRAZIL


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The fossiliferous deposits in the coastal plain of the Rio Grande do Sul State, Southern Brazil, have been known since the late XIX century; however, the biostratigraphic and chronostratigraphic context is still poorly understood. The present work describes the results of electron spin resonance (ESR) dating in eleven fossil teeth of three extinct taxa (Toxodon platensis, Stegomastodon waringi and Hippidion principale) collected along Chui Creek and nearshore continental shelf, in an attempt to assess more accurately the ages of the fossils and its deposits. This method is based upon the analysis of paramagnetic defects found in biominerals, produced by ionizing radiation emitted by radioactive elements present in the surrounding sediment and by cosmic rays. Three fossils from Chui Creek, collected from the same stratigraphic horizon, exhibit ages between (42 +/- 3) Ka and (34 +/- 7) Ka, using the Combination Uptake model for radioisotopes uptake, while a incisor of Toxodon platensis collected from a stratigraphic level below is much older. Fossils from the shelf have ages ranging from (7 +/- 1) 10(5) Ka to (18 +/- 3) Ka, indicating the mixing of fossils of different epochs. The origin of the submarine fossiliferous deposits seems to be the result of multiple reworking and redeposition cycles by sea-level changes caused by the glacial-interglacial cycles during the Quaternary. The ages indicate that the fossiliferous outcrops at Chui Creek are much younger than previously thought, and that the fossiliferous deposits from the continental shelf encompass Ensenadan to late Lujanian ages (middle to late Pleistocene). (C) 2009 Elsevier Ltd and INQUA. All rights reserved.

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There are about 350 million hepatitis B virus (HBV) carriers worldwide and chronic HBV is considered a major public health problem. The objective of the present study was to assess the effectiveness of the nucleos(t)ide analogues tenofovir (TDF) and entecavir (ETV) in the treatment of chronic HBV. A cross-sectional study was carried out from March-December 2013, including all patients with chronic HBV, over 18 years of age, undergoing therapy through the public health system in southern Brazil. Only the data relating to the first treatments performed with TDF or ETV were considered. Retreatment, co-infection, transplanted or immunosuppressed patients were excluded. Six hundred and forty patients were evaluated, of which 336 (52.5%) received TDF and 165 (25.8%) ETV. The other 139 (21.7%) used various combinations of nucleos(t)ide analogues and were excluded. The negativation of viral load was observed in 87.3% and 78.8% and the negativation of hepatitis B e antigen was achieved in 79% and 72% of those treated with ETV or TDF, respectively. Negativation of hepatitis B surface antigen was not observed. There was no occurrence of adverse effects. This is a real-life study demonstrating that long-term treatment with ETV and TDF is both safe and effective.

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Sediment quality from Paranagua Estuarine System (PES), a highly important port and ecological zone, was evaluated by assessing three lines of evidence: (1) sediment physical-chemical characteristics; (2) sediment toxicity (elutriates, sediment-water interface, and whole sediment); and (3) benthic community structure. Results revealed a gradient of increasing degradation of sediments (i.e. higher concentrations of trace metals, higher toxicity, and impoverishment of benthic community structure) towards inner PES. Data integration by principal component analysis (PCA) showed positive correlation between some contaminants (mainly As, Cr, Ni, and Pb) and toxicity in samples collected from stations located in upper estuary and one station placed away from contamination sources. Benthic community structure seems to be affected by both pollution and natural fine characteristics of the sediments, which reinforces the importance of a weight-of-evidence approach to evaluate sediments of PES. (C) 2008 Elsevier B.V. All rights reserved.

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The perception of dental aesthetic appearance may affect social interaction and psychological status, influencing dental needs and the search for treatments. Aim: To investigate the satisfaction with dental appearance and influencing factors among adolescents. Methods: The study was carried out among adolescents aged 14 to 19 years attending a private high school in Brazil. Data on demographic information, the perception of dental appearance, previous aesthetic treatments and wish to perform dental treatments were collected in the school. Data were analyzed using Pearson’s chi-square test or Linear Trend. Multivariate analysis was performed using the Poisson regression. Results: A total of 531 adolescents (Response rate = 98.3%) answered the questionnaire. The prevalence of dissatisfaction with dental appearance was 17.4%. Almost 65% had history of previous orthodontic treatment and 16% performed dental bleaching. Approximately 45% of children wished to undergo orthodontics and 54.8% to bleach their teeth. Dissatisfaction with dental appearance was associated with individuals unsatisfied with dental color (95% IC[1.73;4.32]), those perceiving poor dental alignment (PR3.16 95% IC[2.11;4.72]) and those wishing orthodontic treatment (PR2.9; 95% IC[1.79; 4.70]). Conclusions: The prevalence of dissatisfaction was considerable and was associated with aesthetic concerns such as tooth color, dental alignment and with the wish for orthodontics. In this young population, a large part of adolescents had already performed orthodontic and bleaching treatments and wished to perform those treatments again. Satisfaction with dental appearance could affect the adolescents’ behavior regarding search for dental treatment, thus causing possible overtreatment.

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Introduction: Life expectancy is increasing and becoming a characteristic phenomenon of developed countries and, increasingly, of developing countries, such as Brazil. The aging process causes changes of some physiological functions such as loss of smell, taste, loss of appetite, among other things that end up changing the food intake of these individuals. Objectives: This study aimed to assess food consumption of the young and long-lived elderly in a city in southern Brazil. Methods: A cross-sectional survey conducted through home visits in Palmeira das Missões - RS, Brazil. The sociodemographic, anthropometrical and dietary data were collected through questionnaires and 24-hour recall. The adequacy of nutrients was assessed according to the Dietary Reference Intakes. Data were analyzed using SPSS 18.0 software. Results: The study included 424 older adults, 84,4% (n = 358) aged less than 80 years old and 15,6% (n = 66) older than 80. The intake of energy and protein was insufficient for both young elderly and the oldest. The consumption of vitamins and minerals has been insufficient in all seniors except for iron, which presented an excessive intake. There was a statistically significant difference between the elderly and oldest only for the consumption of lipids and vitamin B12. Conclusion: The majority of studies with elderly corroborate the results found in this article. An inadequate intake of nutrients can develop nutritional deficiencies, and consequently it can result in physiological and pathological changes which would compromise the functional capacity of the elderly. Energy consumption was insufficient and macronutrients were inadequate, both for the young elderly as for the oldest. Additionally, the consumption of vitamins and minerals was insufficient to everyone except the iron, which presented excessive intake for young and oldest elderly.

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Resumo: O gênero mealybug Paracoccus Ezzat & McConnell (Hemiptera: Coccomorpha : ococcidae Pseud ) em todo o mundo tem oito espécies neotropicais descritas, incluindo duas espécies conhecidas do Brasil. Neste artigo, descrevemos uma terceira espécie do Brasil: Paracoccus galzerae Pacheco da Silva & Kaydan sp. n . , com base na morfologia de fêmeas adultas coletadas sobre as raízes da Conyza bonariensis (Asteraceae ) em vinhedos na cidade de Bento Gonçalves, Rio Grande do Sul. Uma chave de identificação revista incluindo a nova espécie é fornecida para a região Neotropical. Abstract: The worldwide mealybug genus Paracoccus Ezzat & McConnell (Hemiptera: Coccomorpha: Pseud ococcidae) has eight described Neotropical species, including two species known from Brazil. In this article, we describe a third species from Brazil: Paracoccus galzerae Pacheco da Silva & Kaydan sp. n., based on the morphology of adult females collected on the roots of Conyza bonariensis (Asteraceae) in vineyards in Bento Gonçalves City, Rio Grande do Sul. A revised identification key including the new species is provided for the Neotropical region.

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Blast is a major disease of rice in Brazil, the largest rice-producing country outside Asia. This study aimed to assess the genetic structure and mating-type frequency in a contemporary Pyricularia oryzae population, which caused widespread epidemics during the 2012/13 season in the Brazilian lowland subtropical region. Symptomatic leaves and panicles were sampled at flooded rice fields in the states of Rio Grande do Sul (RS, 34 fields) and Santa Catarina (SC, 21 fields). The polymorphism at ten simple sequence repeats (SSR or microsatellite) loci and the presence of MAT1-1 or MAT1-2 idiomorphs were assessed in a population comprised of 187 isolates. Only the MAT1-2 idiomorph was found and 162 genotypes were identified by the SSR analysis. A discriminant analysis of principal components (DAPC) of SSR data resolved four genetic groups, which were strongly associated with the cultivar of origin of the isolates. There was high level of genotypic diversity and moderate level of gene diversity regardless whether isolates were grouped in subpopulations based on geographic region, cultivar host or cultivar within region. While regional subpopulations were weakly differentiated, high genetic differentiation was found among subpopulations comprised of isolates from different cultivars. The data suggest that the rice blast pathogen population in southern Brazil is comprised of clonal lineages that are adapting to specific cultivar hosts. Farmers should avoid the use of susceptible cultivars over large areas and breeders should focus at enlarging the genetic basis of new cultivars.

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Temperate fruit production is an important economic activity in Southern Brazil. In this region, persimmon Diospyros kaki L. (Ebenaceae) is grown in small farms for domestic consumption and internal market. Mealybugs are o*en found in at least 50% of the orchards causing damages on fruits due to the honeydew secretion. However, there is a lack of informatin about species composition damaging orchards in Southern Brazil. In this work, we present a survey of mealybugs associated with persimmon trees in the Serra Gaúcha Region, Rio Grande do Sul, Brazil.

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We studied the Paraíba do Sul river watershed , São Paulo state (PSWSP), Southeastern Brazil, in order to assess the land use and cover (LULC) and their implication s to the amount of carbon (C) stored in the forest cover between the years 1985 and 2015. Th e region covers a n area of 1,395,975 ha . We used images made by the Operational Land Imager (OLI) sensor (OLI/Landsat - 8) to produce mappings , and image segmentation techniques to produce vectors with homogeneous characteristics. The training samples and the samples used for classification and validation were collected from the segmented image. To quantify the C stocked in aboveground live biomass (AGLB) , we used an indirect method and applied literature - based reference values. The recovery of 205,690 ha of a secondary Native Forest (NF) after 1985 sequestered 9.7 Tg (Teragram) of C . Considering the whole NF area (455,232 ha), the amount of C accumulated al ong the whole watershed was 3 5 .5 Tg , and the whole Eucalyptus crop (EU) area (113,600 ha) sequester ed 4. 4 Tg of C. Thus, the total amount of C sequestered in the whole watershed (NF + EU) was 3 9 . 9 Tg of C or 1 45 . 6 Tg of CO 2 , and the NF areas were responsible for the large st C stock at the watershed (8 9 %). Therefore , the increase of the NF cover contribut es positively to the reduction of CO 2 concentration in the atmosphere, and Reducing Emissions from Deforestation and Forest Degradation (REDD + ) may become one of the most promising compensation mechanisms for the farmers who increased forest cover at their farms.

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Soils formed in high mountainous regions in southern Brazil are characterized by great accumulation of organic matter (OM) in the surface horizons and variation in the degree of development. We hypothesized that soil properties and genesis are influenced by the interaction of parent materials and climate factors, which differ depending on the location along the altitudinal gradient. The goal of this study was to characterize and classify the soil, evaluate soil distribution, and determine the interactive effects of soil-forming factors in the subtropical mountain regions in Santa Catarina state. Soil samples were collected in areas known for wine production, for a total of 38 modal profiles. Based on morphological, physical, and chemical properties, soils were evaluated for pedogenesis and classified according to the Brazilian System of Soil Classification, with equivalent classes in the World Reference Basis (WRB). The results indicated that pedogenesis was strongly influenced by the parent material, weather, and relief. In the areas where basic effusive rocks (basalt) were observed, there was formation of extensive areas of clayey soils with reddish color and higher iron oxide contents. There was a predominance of Nitossolos Vermelhos and Háplicos (Nitisols), Latossolos Vermelhos (Ferralsols), and Cambissolos Háplicos (Cambisols), highlighting the pedogenetic processes of eluviation, illuviation of clay, and latosolization in conditions of year-long, large-volume, well-distributed rainfall and stability of land forms. In areas with acid effusive rocks (rhyodacites), medial or clayey soils were observed with lower iron oxide content, invariably acidic, and with low base content. For these soils, relief promoted substantial removal of material, resulting in intense rejuvenation, with a predominance of Cambissolos Háplicos (Cambisols) and lesser occurrence of Nitossolos Brunos (Nitisols) and Neossolos Litólicos (Leptosols). Soils formed from sedimentary rocks also tended to be more acidic, but with higher sand content, and the soils identified were Cambissolos Háplicos and Húmicos (Cambisols). Cluster analysis separated the soil profiles into three groups: the first and largest was formed by profiles originating from sedimentary rocks and rhyodacites; the second, smaller group was formed by four profiles in the Água Doce region (acidic rocks); and the third was formed by profiles derived from basalt. Discriminant analysis was effective in grouping soil classes. Thus, the study highlighted the importance of geology in the formation of soils in this landscape associated with climate and relief.