432 resultados para Northeastern Backlands of Brazil


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Two hundred and five animals were cytogenetically studied. They were related to a male goat called 'Harald', imported from Switzerland, who was a t 5 15 chromosomic translocation carrier. 29.27% of the analyzed animals were heterozygous and 4.88% were homozygous. All carrying animals were found in Botucatu, Limeira and São Manuel city in Brazil. Descendants of this buck were sold in several regions of Brazil, and may have spread this aberration. © 1992.

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The integration of outcrop and subsurface information, including micropaleontological data, facies and sequence stratigraphic studies, and oxygen isotope analysis, allow us to present a new stratigraphic model for the Cretaceous continental deposits of the Bauru Group, Brazil. Thirty-eight fossil taxa were recovered from these deposits, including 29 species of ostracodes and 9 species of charophytes. Seven of these ostracode species and three subspecies are new and formally described here. The associations of Chara barbosai - Ilyocypris cf. riograndensis, found in the Adamantina Formation, and Amblyochara sp. - Neuquenocypris minor mineira nov. subsp., found in the Marília Formation. Ponte Alta Member, represent two distinct groups that are respectively Turonian-Santonian and Maastrichtian (probably Late Maastrichtian) in age. Therefore, a hiatus, encompassing more than 11 Ma, separates those two formations. From bottom to top, four depositional cycles were recognized in the Bauru Group in western São Paulo: cycles 1 and 2 belong to Caiuá Formation (fluvio-lacustrine and lacustrine deposits in the Presidente Prudente region), cycle 3 to the Santo Anastácio and lower Adamantina Formation (respectively fluvial and lacustrine deposits), and cycle 4 to the upper Adamantina Formation (fluvio-lacustrine facies). An erosional unconformity separates the Caiuá and Santo Anastácio Formations (between cycles 2 and 3). The Marília Formation is a distinct unit from the underlying succession; it does not occur in western São Paulo, but is found in restricted areas of São Paulo, Minas Gerais, Mato Grosso do Sul and Goiás States. During the deposition of the Bauru Group (Aptian? to Maastrichtian) the climate was hot and arid-semiarid. Shallow lakes underwent fluctuations in expansion (wet phases) and contraction (dry phases), as well as variations in salinity. During the deposition of the Adamantina Formation (Turonian-Santonian) there were long, dry periods that caused segmentation of large lakes (due to topographic irregularities in the basaltic substrate) and sometimes exposures of the lake floors; when flooded these lake floors were colonized by extensive meadows of single species of charophytes. Small ephemeral ponds, that were hydrochemically unstable and colonized by multiple species of charophytes, were the depositional sites for the marls and mudstones of Ponte Alta Member (Maastrichtian, Late Maastrichtian?). Our micropaleontological age control, combined with the Late Cretaceous ages of volcanic ashes found in the southeastern Brazil coastal basins, and the stratigraphic position of analcimites from the Jaboticabal-SP region, suggest a Late Coniacian-Santonian age for important magmatic events occurred in the interior of Brazil (north-central São Paulo State, Triângulo Mineiro, and southwestern Goiás State).

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The increased demand for juvenile tambaqui Colossoma macropomum for grow-out ponds and stocking programs in the Amazon state of Brazil has increased the transportation of this species. This study was designed to determine the optimum density of juvenile tambaqui during transportation in closed containers. Fish (51.9 ± 3.3 g and 14.9 ± 0.4 cm) were packed in sealed plastic bags and transported for 10 h at four densities: 78, 156, 234, and 312 kg/m3. After transportation, fish from each density were kept in separate 500-L tanks for 96 h. Mortality, 96-h cumulative mortality, water quality, and blood parameters (hematocrit, plasma cortisol, and glucose) were monitored. Fish mortality after transportation was significantly lower at densities of 78 and 156 kg/m3 than at 234 and 312 kg/m3. Cumulative mortality was significantly lower at a density of 78 kg/m3. Dissolved oxygen after 10 h of transportation remained high at a density of 78 kg/m3, but reached critically low values at all other densities. Ammonia concentration was highest at the lowest density and was lower at higher densities. Carbon dioxide concentration was lowest at the density of 78 kg/m3 but higher in the other treatments. Plasma glucose and cortisol increased significantly immediately after transportation at densities of 156, 234, and 312 kg/m3, returning to control values by 24 h. The best density for juvenile tambaqui during a 10-h transportation haul in a closed container was 78 kg/m3. At this density there was no fish mortality, water quality was kept within acceptable values, and fish were not stressed.

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This study describes, for the first time, the occurrence of two patterns of honey storage in nests of the paper wasp Polistes simillimus. During the period of January of 1997 to September of 2000 we visited 262 colonies of P. simillimus, found at several places in States of São Paulo and Minas Gerais, in the southeast region of Brazil. Only in 2.67% of the colonies of P. simillimus searched presented the behavior of honey storage. Two of these colonies were in the pre-emergency phase, two in the post-emergency and three in decline. The results suggest that the honey storage can be correlated with the number of present individuals in the colony, because the colonies in decline, with larger number of individuals, presented many more cells occupied with honey than the nests in pre and post-emergency. There was not a pattern for the distribution of the cells with honey in the nests in decline. The honey storage in the colonies in pre and post-emergency of P. simillimus, suggests a strategy to increase success of foraging activity in the function of parental care. Already for the colonies in decline, this strategy seems to be associated with the individuals' survival in the aggregation, since the wasps are awaiting the passage of the unfavorable climatic conditions for the dispersion and foundation of new colonies.

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A comparative study was made regarding the clinical and hematological alterations caused by isolates of Babesia bigemina from southeastern, northeastern and northern Brazil in experimentally infected Nelore calves. Eighteen calves between 7 and 9 months of age, without antibodies against Babesia sp and raised free from ticks, were used. Three animals were previously inoculated with 2.0×109 parasitic erythrocytes (PE) for each stabilate. The other 15 calves were subdivided into three groups, with five animals each, that were subinoculated with 1.0×1010 PE of the respective isolates. The clinical and hematological alterations were evaluated by the determination of parasitaemia, haemogram, plasmatic fibrinogen, reticulocyte count, descriptive analysis of the bone marrow and erythrocytic osmotic fragility, for 30 days, totalizing seven moments of observation. The follow-up of the immunological response by the indirect fluorescent antibody test was carried out daily until the 10th day after inoculation (DAI) and after that, on the 15th, 20th, 25th and 30th DAI. A mild clinical manifestation of the disease was observed. The laboratory findings revealed low levels of parasitaemia; decrease of the erythrogram values; absence of reticulocytes, initial decrease in the total count of leukocytes, neutrophils and lymphocytes with a posterior elevation of the number of these cells; hypercellularity of the erythrocytic series and decrease of the myeloid: erythroid relation which was more accentuated between the 8th and 12th DAI, and an increase of the erythrocytic osmotic fragility in the groups inoculated with the Southeast and Northeast isolates. None of the three isolates of B. bigemina gave rise to the clinical characteristic form of the disease, although they induced an humoral immune response.

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Procornitermes araujoi is a mandibulate termite of the Nasutitermitinae subfamily that builds mounds in savannas of the Central and Southeastern regions of Brazil. This paper reports the occurrence of three imaginai queens in the same nest of this termite located in Rio Claro, (SP), Brazil. The associated queens were similar in size, degree of physogastry, and pigmentation. The king was not found. The polygyny and nest architecture of P. araujoi are discussed.

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A pioneer GPR - Ground Penetrating Radar - survey was carried out in the Pantanal of Mato Grosso State, westcentral region of Brazil. Fieldwork acquisitions were carried out in February/2001 and August/2002 in order to understand avulsion processes that are occurring within the Taquari alluvial megafan. The main subjects were to map channel, crevasses and floodplain morphology, as well as active sedimentary bedforms. Many GPR profiles were surveyed in the medium and lower Taquari River course. Subaqueous megaripples and exposed sand bars inside the Taquari channel were identified in the medium fan area. Similar features were observed in the lower fan channels, where there are also many crevasses in the marginal levees. During the flooding seasons the flow splays out in the floodplain where new distributary channels are being formed. As shown by GPR data, in the lower fan the Taquari channel is topographically higher than the adjacent floodplain, situation in which avulsion is a natural process of river course shifting. The lack of information about river morphology and dynamics is a major strain to better understand the sediment transport and the avulsion processes in the Taquari megafan. In this context, the GPR data obtained in wet and dry seasons, integrated to sedimentological information, have been very important to characterize the fluvial dynamics and the avulsion phenomena.

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Fuel cell as MCFC (molten carbonate fuel cell) operate at high temperatures, and due to this issue, cogeneration processes may be performed, sending heat for own process or other purposes as steam generation in an industry. The use of ethanol for this purpose is one of the best options because this is a renewable and less environmentally offensive fuel, and cheaper than oil-derived hydrocarbons (in the case of Brazil). In the same country, because of technical, environmental and economic advantages, the use of ethanol by steam reforming process have been the most investigated process. The objective of this study is to show a thermodynamic analysis of steam reforming of ethanol, to determine the best thermodynamic conditions where are produced the highest volumes of products, making possible a higher production of energy, that is, a most-efficient use of resources. To attain this objective, mass and energy balances are performed. Equilibrium constants and advance degrees are calculated to get the best thermodynamic conditions to attain higher reforming efficiency and, hence, higher electric efficiency, using the Nernst equation. The advance degree of reforming increases when the operation temperature also increases and when the operation pressure decreases. But at atmospheric pressure (1 atm), the advance degree tends to the stability in temperatures above 700°C, that is, the volume of supplemental production of reforming products is very small for the high use of energy resources necessary. Reactants and products of the steam-reforming of ethanol that weren't used may be used for the reforming. The use of non-used ethanol is also suggested for heating of reactants before reforming. The results show the behavior of MCFC. The current density, at same tension, is higher at 700°C than other studied temperatures as 600 and 650°C. This fact occurs due to smaller use of hydrogen at lower temperatures that varies between 46.8 and 58.9% in temperatures between 600 and 700°C. The higher calculated current density is 280 mA/cm 2. The power density increases when the volume of ethanol to be used also increases due to higher production of hydrogen. The highest produced power at 190 mW/cm 2 is 99.8, 109.8 and 113.7 mW/cm2 for 873, 923 and 973K, respectively. The thermodynamic efficiency has the objective to show the connection among operational conditions and energetic factors, which are some parameters that describes a process of internal steam reforming of ethanol.

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The slender catshark Schroedericthys tenuis Springer, 1966, originally described from two immature males, is redescribed on the basis of 12 specimens of both sexes, juveniles and adults (as well as the holotype and paratype). The supplementary specimens were collected off the northern coast of Brazil between Amapá and Pará states. Aspects of its external morphology, color pattern, dermal denticles, dentition, vertebral counts, and the cephalic, clasper and pectoral fin skeleton are described in detail and fully illustrated. These features are compared with those of congeneric species. Our observations support preliminary results of work in progress that S. maculatus Springer, 1966, S. tenuis and S. saurisqualus Soto, 2003 form a monophyletic group, mostly on the basis of neurocranial morphology, and that S. bivius (Smith, 1838) and S. chilensis (Guichenot, 1848) should be removed from Schroederichthys. Copyright © 2006 Magnolia Press.

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Objective: The International Study of Asthma and Allergies in Childhood (ISAAC) is a standardized method that allows international and regional comparisons of asthma and allergic diseases prevalence. The objective of this study was to evaluate the prevalence of rhinitis and related symptoms among 6-7 year-old children (SC) and 13-14 year-old adolescents (AD) from 20 Brazilian cities applying the ISAA C's standardized written questionnaire (WQ). Methods: ISAAC's WQ was applied to 23,422 SC and 58,144 AD living in different regions of Brazil: North (N), Northeast (NE), Middle West (MW), Southeast (SE), and South (S). Results: The prevalence of rhinoconjunctivitis in the last year ranged from 10.3% to 17.4% and from 8.9% to 28.5% among SC and AD, respectively. Considering SC the highest values were observed in SE region. In NE, the prevalence in countryside centres was higher than those along the coast. Among AD, the highest values were observed in N and S regions, mainly in Pará (Belém). The evaluation of populations probably with the same genetic background has shown higher prevalence among those living in urban centres (capital) in comparison to those in the countryside. Conclusions: The prevalence of rhinitis and related symptoms were variable and predominate in Brazilian N and NE centres.

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This study was performed in the southern and southeastern regions of Brazil, visiting numerous municipalities, over a period of 25 years, excavating nests of 12 species of leaf-cutting ants of the Acromyrmex genus. Larvae and pupae of Microdon tigrinus were found only in nests of the leaf-cutting ant Acromyrmex coronatus, indicating high specificity. Observation showed that larvae and pupae were well accepted in the nests and the adults, immediately after puparia eclosion and prior to wing distension, were not attacked by the workers, suggesting that they produce semiochemicals for a short time period until they arrive outside the Acromyrmex coronatus nest. It was postulated that these larvae feed on the organic detritus of the nest, as shown for Microdon larvae of other species.

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Calathea louisae is an herbaceous ornamental plant native of Brazil whose cut foliage has potential to be used as a new product for the local ornamental market, as well as the international market, due to its decorative dark green leaves with greenish white splotches along midrib, and purple undersides. The objective of this study was to evaluate pulse treatments of benzyladenine and gibberellic acid for maintaining quality and extending keepability of foliage. The experiment was conducted in a complete randomized design with three replications (three stems in each vase) and seven treatments: distilled water (control) and pulsing cut petioles in benzyladenine or gibberellic acid for 4 h at 100, 250 and 500 mg L-1. The senescence symptoms were characterized by leaf rolling and a decrease in the angle formed between leaf and petiole as a response to water stress. Gibberellic acid or benzyladenine pulse treatments (250 and 500 mg L-1) significantly extended the longevity of cut foliage compared to the control. Gibberellic acid pulse (250 and 500 mg L-1) maintained leaves' green coloration and brightness for a longer time compared to control and benzyladenine pulse. Pulsing with gibberellic acid or benzyladenine (at all tested concentrations) maintained upright leaves for a longer time, showing a significantly higher angle between leaf and petiole compared to control. Foliage pulsed with gibberellic acid (500 mg L-1) showed a significantly higher leaf relative water content, a significantly smaller loss of accumulated fresh mass percentage compared to control and other gibbberellic acid and benzyladenine treatments.

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Malaria is an endemic parasitosis and its causitive agent, Plasmodium, has a metabolism linked to iron supply. HFE is a gene with the polymorphisms C282Y and H63D, which are associated with a progressive iron accumulation in the organism leading to a disease called hereditary hemochromatosis. The aim of the present study was to determine the allelic and genotypic frequencies of the HFE gene polymorphisms in malaria patients and blood donors from the Brazilian Amazon region. We screened 400 blood donors and 400 malaria patients for the HFE C282Y and H63D polymorphisms from four states of the Brazilian Amazon region by polymerase chain reaction and restriction fragment length polymorphism analysis. We did not find any C282Y homozygous individuals, and the only five heterozygous individuals detected were from Pará State. The most frequent genotype in the North region of Brazil was the H63D heterozygote, in both study groups. Our results contribute to the concept that the Brazilian Amazon region should not be regarded as a single entity in South America. These polymorphisms did not influence the symptoms of malaria in the population studied, as neither severe signs nor high parasitemia were observed. Therefore, different hereditary hemochromatosis diagnostic and control measures must be developed and applied within its diverse locations. Investigations are currently being carried out in our laboratory in order to determine the importance of the coexistence of hereditary hemochromatosis in patients affected by parasitic diseases, such as malaria. ©FUNPEC-RP.

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Equatorial F region vertical plasma drifts, spread F and anomaly responses, in the south American longitude sector during the superstorm of 30 October 2003, are analyzed using data from an array of instruments consisting of Digisondes, a VHF radar, GPS TEC and scintillation receivers in Brazil, and a Digisonde and a magnetometer in Jicamarca, Peru. Prompt penetrating eastward electric field of abnormally large intensity drove the F layer plasma up at a velocity ∼1200 ms -1 during post dusk hours in the eastern sector over Brazil. The equatorial anomaly was intensified and expanded poleward while the development of spread F/plasma bubble irregularities and GPS signal scintillations were weaker than their quiet time intensity. Significantly weaker F region response over Jicamarca presented a striking difference in the intensity of prompt penetration electric field between Peru and eastern longitudes of Brazil. The enhanced post dusk sector vertical drift over Brazil is attributed to electro-dynamics effects arising energetic particle precipitation in the South Atlantic Magnetic Anomaly (SAMA). These extraordinary results and their longitudinal differences are presented and discussed in this paper. Copyright 2008 by the American Geophysical Union.