998 resultados para SE Brazilian coast (23 degrees S and 42 degrees W)


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Schizophrenia is a severe psychiatric disorder with frequent recurrent psychotic relapses and progressive functional impairment. It results from a poorly understood gene-environment interaction. The gene encoding catechol-O-methyltransferase (COMT) is a likely candidate for schizophrenia. Its rs165599 (A/G) polymorphism has been shown to be associated with alteration of COMT gene expression. Therefore, the present study aimed to investigate a possible association between schizophrenia and this polymorphism. The distribution of the alleles and genotypes of this polymorphism was investigated in a Brazilian sample of 245 patients and 834 controls. The genotypic frequencies were in Hardy-Weinberg equilibrium and no statistically significant differences were found between cases and controls when analyzed according to gender or schizophrenia subtypes. There was also no difference in homozygosis between cases and controls. Thus, in the sample studied, there was no evidence of any association between schizophrenia and rs165599 (A/G) polymorphism in the non-coding region 3' of the COMT gene.

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The ALRED construction is a lightweight strategy for constructing message authentication algorithms from an underlying iterated block cipher. Even though this construction's original analyses show that it is secure against some attacks, the absence of formal security proofs in a strong security model still brings uncertainty on its robustness. In this paper, aiming to give a better understanding of the security level provided by different authentication algorithms based on this design strategy, we formally analyze two ALRED variants-the MARVIN message authentication code and the LETTERSOUP authenticated-encryption scheme,-bounding their security as a function of the attacker's resources and of the underlying cipher's characteristics.

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Approximately 370 brachyuran species have so far been recorded from the Brazilian coast, 123 of which have had their larval stages fully or partially described. The pictorial guide allows the identification of the first zoea of 110 species. The remaining 13 species with known larval stages are treated to the genus level because of difficulties in the morphological differentiation of closely related species.

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Different components of the mixed function oxidase (MFO) system and the levels of fluorescent aromatic compounds in bile (FACs) were measured in Cathorops spixii in order to assess the impact of polycyclic aromatic hydrocarbons (PAHs). Fish were sampled in an estuary (Santos/Sao Vicente) with a history of contamination by PAHs, mainly due to the presence of the industrial complex of Cubatao city and of another of low anthropogenic influence (Cananeia) on the Brazilian coast. FACs were higher in fish from the polluted site, and the PAH 5 and 6-ring metabolites were the most frequent - with 14% and 15%, respectively. Levels of the different components of the MFO system showed the same variation profile as the FACs for both estuaries. Therefore, the values found for somatic indexes and biomarkers with data of bile PAH metabolites indicate the presence of organic contaminants, especially in the area subject to the influence of the industrial complex on the Santos/Sao Vicente estuary.

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Brazil is one of the largest mango producers and the third largest mango exporter worldwide. Irradiation treatment and its commercial feasibility have been studied in our country to make it possible to develop new markets and, consequently, to compete with the major exporters of mangoes, Mexico and India. This work was designed to compare irradiation treatment with the hot water dip treatment in mangoes cv. Tommy Atkins for export and to verify that the main attributes for acceptance, color and texture, as well as carbohydrate and organic acid contents, were maintained. In this study, the fruit was divided into groups: control, hot water dip-treated (46 degrees C for 90 min), and irradiation-treated at doses of 0.4 kGy and 1.0 kGy. The fruit was stored at low temperature (11 degrees C +/- 2) for 14 days and then at room temperature (23 degrees C +/- 2) until the end of the study. The results indicated that the fruit given a dose of 1.0 kGy remained in a less advanced stage of ripening (stage 3) throughout the storage period, but experienced a greater loss of texture in the beginning of the experiment. It was noted that only the control group had higher levels of citric acid and succinic acid on the last day of the experiment. There were no significant differences in the total sugar content between any treatment groups. Gamma radiation can be used as a quarantine treatment and does not interfere negatively with the quality attributes of mangoes. (C) 2012 Elsevier Ltd. All rights reserved.

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The present study deals with the determination of the activation energy for the thermal decomposition of two renewable fuels crude glycerin and beef tallow. The activation energies were investigated by using a thermogravimetric analyzer (TGA) in the temperature range of 25-600 degrees C in atmosphere of synthetic air. The TG curves of the thermal decomposition process of both samples were divided into several phases and the second, called PH2, was chosen for the kinetic study because it is associated with the combustion ignition. Differential Thermal Analysis (DTA) showed an endothermic event at the PH2 region for the crude glycerin corresponding to devolatilization, while for beef tallow, this step presented an exothermic event, called LTO (low-temperature oxidation), which is correlated with devolatilization followed by combustion. For the entire PH2, activation energy values for crude glycerin were between 90 kJ mol(-1) and 42 kJ mol(-1), while for the beef tallow they ranged from 50 kJ mol(-1) to 113 kJ mol (1). The activation energy values obtained at the pre-ignition stage - conversion between 0 and 0.45 - showed that the crude glycerin with higher values requires an additional energetic support at the start of combustion processes and the beef tallow ignites more easily, presenting lower values. According to the Wolfer's equation, a direct relation between the activation energy and the ignition delay is established and the results of this study provides useful data for the development and design of new combustion chambers and engines when non-traditional fuels are used as feedstock. (C) 2012 Elsevier Ltd. All rights reserved.

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Sugarcane (Saccharum spp.) and palm tree (Elaeis guianeensis) are crops with high biofuel yields, 7.6 m(3) ha (1) y(-)1 of ethanol and 4 Mg ha(-1) y(-1) of oil, respectively. The joint production of these crops enhances the sustainability of ethanol. The objective of this work was comparing a traditional sugarcane ethanol production system (TSES) with a joint production system (JSEB), in which ethanol and biodiesel are produced at the same biorefinery but only ethanol is traded. The comparison is based on ISO 14.040:2006 and ISO 14044:2006, and appropriate indicators. Production systems in Cerrado (typical savannah), Cerradao (woody savannah) and pastureland ecosystems were considered. Energy and carbon balances, and land use change impacts were evaluated. The joint system includes 100% substitution of biodiesel for diesel, which is all consumed in different cropping stages. Data were collected by direct field observation methods, and questionnaires applied to Brazilian facilities. Three sugarcane mills situated in Sao Paulo State and one palm oil refinery located in Para State were surveyed. The information was supplemented by secondary sources. Results demonstrated that fossil fuel use and greenhouse gas emissions decreased, whereas energy efficiency increased when JSEB was compared to TSES. In comparison with TSES, the energy balance of JSEB was 1.7 greater. In addition, JSEB released 23% fewer GHG emissions than TSES. The ecosystem carbon payback time for Cerrado, Cerradao, and Degraded Grassland of JSEB was respectively 4, 7.7 and -7.6 years. These are typical land use types of the Brazilian Cerrado region for which JSEB was conceived. (C) 2012 Elsevier Ltd. All rights reserved.

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Background: Bugula is a speciose genus of marine bryozoans, represented by both endemic and cosmopolitan species distributed in tropical and temperate waters and important to marine biologists because of the occurrence of many species in harbor and fouling communities, therefore as potential invaders. The southeastern Brazilian coast in the southern Atlantic hosts the highest known diversity of the genus, a status intimately associated with the intensity of collecting efforts. Methodology: Morphological data based on the examination of living specimens, scanning electron and light microscopic images, and morphometric analyses were used to assess the diversity of Bugula along the coastal areas of southern, northeastern, and southeastern Brazil. In this study, morphological species boundaries were based mainly on avicularian characters. For two morphologically very similar species, boundaries are partially supported by 16 S rDNA molecular data. Results: Nine species are newly described from Brazil, as follows: Bugula bowiei n. sp. (= Bugula turrita sensu Marcus, 1937) from the southern, northeastern, and southeastern coasts; Bugula foliolata n. sp. (= Bugula flabellata sensu Marcus, 1938), Bugula guara n. sp., Bugula biota n. sp. and Bugula ingens n. sp from the southeastern coast; Bugula gnoma n. sp. and Bugula alba n. sp. from the northeastern coast; Bugula rochae n. sp. (= Bugula uniserialis sensu Marcus, 1937) from the southern coast; and Bugula migottoi n. sp., from the southeastern and southern coasts. Conclusion: The results contribute to the morphological characterization and the knowledge of the species richness of the genus in the southwestern Atlantic (i.e., Brazil), through the description of new species in poorly sampled areas and also on the southeastern coast of that country. Additionally, the taxonomic status of the Brazilian specimens attributed to B. flabellata, B. turrita and B. uniserialis are clarified by detailed studies on zooidal and avicularia morphology.

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Extremophiles are organisms adapted to grow at extreme ranges of environmental variables, such as high or low temperatures, acid or alkaline medium, high salt concentration, high pressures and so forth. Most extremophiles are micro-organisms that belong to the Archaea and Bacteria domains, and are widely spread across the world, which include the polar regions, volcanoes, deserts, deep oceanic sediments, hydrothermal vents, hypersaline lakes, acid and alkaline water bodies, and other extreme environments considered hostile to human life. Despite the tropical climate, Brazil has a wide range of ecosystems which include some permanent or seasonally extreme environments. For example, the Cerrado is a biome with very low soil pH with high Al+3 concentration, the mangroves in the Brazilian coast are anaerobic and saline, Pantanal has thousands of alkaline-saline lakes, the Caatinga arid and hot soils and the deep sea sediments in the Brazilian ocean shelf. These environments harbour extremophilic organisms that, coupled with the high natural biodiversity in Brazil, could be explored for different purposes. However, only a few projects in Brazil intended to study the extremophiles. In the frame of astrobiology, for example, these organisms could provide important models for defining the limits of life and hypothesize about life outside Earth. Brazilian microbiologists have, however, studied the extremophilic micro-organisms inhabiting non-Brazilian environments, such as the Antarctic continent. The experience and previous results obtained from the Brazilian Antarctic Program (PROANTAR) provide important results that are directly related to astrobiology. This article is a brief synopsis of the Brazilian experience in researching extremophiles, indicating the most important results related to astrobiology and some future perspectives in this area. Received 29 February 2012, accepted 25 May 2012, first published online 11 July 2012

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This paper presents the offorts to calculate the geoid model for Brazil. It is limited by 6 degrees N and 35 degrees S in latitude and 30 degrees W and 75 degrees W in longitude. The terrestrial gravity data for the continent have been updated by means of the most recent surveys in Brazil and in the neighbour countries. The complete Bouguer and Helmert gravity anomalies have been derived through the Canadian package SHGEO. The short wavelength component was estimated via FFT. The geopotential model EGM2008 was used as a reference field restricted to degree and order 150. The model was validated over 844 GPS observations on Bench Marks of the spirit leveling network. The height anomalies plus a topography dependent correction term derived from EGM2008 (degree 2190 and order 2159), GO_CONS_GCF_2_DIR_R2 (degree and order 240), GOCO02S (degree and order 250), EIGEN 51C (degree and order 359) and EIGEN 6C (degree and order 1420), geoidal height derived from MAPGEO2004 (old official geoid model in Brazil) have also been compared to the GPS points on Bench Marks.

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Festuccia WT, Blanchard PG, Oliveira TB, Magdalon J, Paschoal VA, Richard D, Deshaies Y. PPAR gamma activation attenuates cold-induced upregulation of thyroid status and brown adipose tissue PGC-1 alpha and D2. Am J Physiol Regul Integr Comp Physiol 303: R1277-R1285, 2012. First published October 24, 2012; doi:10.1152/ajpregu.00299.2012.-Here, we investigated whether pharmacological PPAR gamma activation modulates key early events in brown adipose tissue (BAT) recruitment induced by acute cold exposure with the aim of unraveling the interrelationships between sympathetic and PPAR gamma signaling. Sprague-Dawley rats treated or not with the PPAR gamma ligand rosiglitazone (15 mg.kg(-1).day(-1), 7 days) were kept at 23 degrees C or exposed to cold (5 degrees C) for 24 h and evaluated for BAT gene expression, sympathetic activity, thyroid status, and adrenergic signaling. Rosiglitazone did not affect the reduction in body weight gain and the increase in feed efficiency, VO2, and BAT sympathetic activity induced by 24-h cold exposure. Rosiglitazone strongly attenuated the increase in serum total and free T4 and T3 levels and BAT iodothyronine deiodinase type 2 (D2) and PGC-1 alpha mRNA levels and potentiated the reduction in BAT thyroid hormone receptor (THR) beta mRNA levels induced by cold. Administration of T3 to rosiglitazone-treated rats exacerbated the cold-induced increase in energy expenditure but did not restore a proper activation of D2 and PGC-1 alpha, nor further increased uncoupling protein 1 expression. Regarding adrenergic signaling, rosiglitazone did not affect the changes in BAT cAMP content and PKA activity induced by cold. Rosiglitazone alone or in combination with cold increased CREB binding to DNA, but it markedly reduced the expression of one of its major coactivators, CREB binding protein. In conclusion, pharmacological PPAR gamma activation impairs short-term cold elicitation of BAT adrenergic and thyroid signaling, which may result in abnormal tissue recruitment and thermogenic activity.

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Objective. To compare the clinical, demographic, and serologic characteristics and the treatment of patients diagnosed with ankylosing spondylitis (AS) from Europe (EU) and Latin America (LA). Methods. We included 3439 patients from national registries: the Spanish Registry of Spondyloarthritis (REGISPONSER), the Belgian registry (ASPECT), and the Latin American Registry of Spondyloarthropathies (RESPONDIA). We selected patients with diagnosis of AS who met the modified New York classification criteria. Demographic, clinical, disease activity, functional, and metrological measurement data were recorded. Current treatment was recorded. The population was classified into 2 groups: patients with disease duration < 10 years and those with disease duration >= 10 years. A descriptive and comparative analysis of variables of both groups was carried out. Results. There were 2356 patients in EU group and 1083 in LA group. Prevalence of HLA-B27 was 71% in LA group and 83% in EU group (p < 0.001). We found a greater frequency of peripheral arthritis and enthesitis (p < 0.001) in the LA population; prevalence of arthritis was 57% in LA and 42% in EU, and for enthesitis, 54% and 38%. Except for treatment with anti-tumor necrosis factor (anti-TNF), the use of nonsteroidal antiinflammatory drugs (NSAID), corticosteroids, and disease-modifying antirheumatic drugs (DMARD), and the association of anti-TNF and methotrexate use showed a significant difference (p < 0.001) in the 2 populations. Conclusion. The principal differences in the clinical manifestations of patients with AS from EU and LA were the greater frequency of peripheral arthritis and enthesitis in LA group, the higher percentage of HLA-B27 in EU group, and the form of treatment, with a greater use of NSAID, steroids, and DMARD in the LA group. (First Release Nov 15 2012; J Rheumatol 2012;39:2315-20; doi:10.3899/jrheum.110687)

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We provide a detailed account of the spatial structure of the Brazilian sardine (Sardinella brasiliensis) spawning and nursery habitats, using ichthyoplankton data from nine surveys (1976-1993) covering the Southeastern Brazilian Bight (SBB). The spatial variability of sardine eggs and larvae was partitioned into predefined spatial-scale classes (broad scale, 200-500 km; medium scale, 50-100 km; and local scale, <50 km). The relationship between density distributions at both developmental stages and environmental descriptors (temperature and salinity) was also explored within these spatial scales. Spatial distributions of sardine eggs were mostly structured on medium and local scales, while larvae were characterized by broad-and medium-scale distributions. Broad-and medium-scale surface temperatures were positively correlated with sardine densities, for both developmental stages. Correlations with salinity were predominantly negative and concentrated on a medium scale. Broad-scale structuring might be explained by mesoscale processes, such as pulsing upwelling events and Brazil Current meandering at the northern portion of the SBB, while medium-scale relationships may be associated with local estuarine outflows. The results indicate that processes favouring vertical stability might regulate the spatial extensions of suitable spawning and nursery habitats for the Brazilian sardine.

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Large conurbations are a significant source of the anthropogenic pollution and demographic differences between cities that result in a different pollution burden. The metropolitan area of Sao Paulo (MASP, population 20 million) accounts for one fifth of the Brazilian vehicular fleet. A feature of MASP is the amount of ethanol used by the vehicular fleet, known to exacerbate air quality. The study describes the diurnal behaviour of the submicron aerosol and relies on total particle number concentration, particle number size distribution, light scattering and light absorption measurements. Modelled planetary boundary layer (PBL) depth and air mass movement data were used to aid the interpretation. During morning rush-hour, stagnant air and a shallow PBL height favour the accumulation of aerosol pollution. During clear-sky conditions, there was a wind shift towards the edge of the city indicating a heat island effect with implications on particulate pollution levels at the site. The median total particle number concentration for the submicron aerosol typically varied in the range 1.6 x 10(4)-3.2 x 10(4) cm(-3) frequently exceeding 4 x 10(4) cm-3 during the day. During weekdays, nucleation-mode particles are responsible for most of the particles by numbers. The highest concentrations of total particle number concentrations and black carbon (BC) were observed on Fridays. Median diurnal values for light absorption and light scattering (at 637 nm wavelength) varied in the range 12-33 Mm(-1) and 21-64 Mm(-1), respectively. The former one is equal to 1.8-5.0 mu g m(-3) of BC. The growth of the PBL, from the morning rush-hour until noon, is consistent with the diurnal cycle of BC mass concentrations. Weekday hourly median single-scattering albedo (omega(0)) varied in the range 0.59-0.76. Overall, this suggests a top of atmosphere (TOA) warming effect. However, considering the low surface reflectance of urban areas, for the given range of omega(0), the TOA radiative forcing can be either positive or negative for the sources within the MASP. On the average, weekend omega(0) values were 0.074 higher than during weekdays. During 11% of the days, new particle formation (NPF) events occurred. The analysed events growth rates ranged between 9 and 25 nm h(-1). Sulphuric acid proxy concentrations calculated for the site were less than 5% of the concentration needed to explain the observed growth. Thus, other vapours are likely contributors to the observed growth.

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The increased pollution in the aquatic ecosystem has led to the investigation of toxic elements in sea water by using marine organisms to assess marine pollution from human activities. Among these organisms, the mollusks bivalves have been used as biomonitors since they can accumulate trace elements and other substances, without the occurrence of their death. In this study, Perna perna mussels were transplanted from a mussel farm (reference region) to four sites located in coastal regions of So Paulo State, Brazil, close to anthropic discharge areas. Vanadium was determined in mussel tissues by instrumental neutron activation analysis (INAA). Quality control of V analysis was checked by analyzing biological reference materials and the results obtained were precise and in good agreement with the certified values. Comparisons between the V concentrations obtained in transplanted mussels indicated that those from So Sebastio region, close to an oil terminal presented the highest concentration of this element, during spring.