182 resultados para 2177


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At the Pontalina region, the Magmatic Arc of Goiás is constituted by orthogneisses, metasediments, metaultramafics and metamafic/metabasics, geochemically related to island arcs. Mineral assemblages related to metamorphic peak observed in the study area are typically of the amphibolite facies and were generated before or during the initial stage of the development of the main foliation (S n). Thermobarometric data show the P and T conditions for the amphibole + plagioclase and plagioclase + garnet + amphibole assemblages in the metamafic/metabasic rocks correspond to amphibolite facies (medium to upper grade), and plot in the kyanite stability field. The results indicate that the metamorphic peak (M1) in the amphibolite facies (medium up to upper grade) reached temperatures slightly higher than 700°C, not exceeding 775°C, under conditions of medium pressure (∼10 kbar). Thermobarometric and petrographic data, related to the metamorphism, indicate a clockwise P-T path for the surrounding rocks.

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The effects of temperature on the rate of biological processes such as the germination are reported in several papers. The analysis of the thermal effect can be performed either from numerical indices or germination curves, which is usually presented as the accumulated percentage of germination versus time. Such curves can be fitted by empirical models and generally they offer a better description of the time-course of germination than single-value indices. On the other hand, in analyzing the germination curves, a question arises whether the model parameters have biological meaning. Thus, it is desirable that the model parameters both describe properly the germination curve and have biological meaning, which often does not occur. Considering the involvement of populations and percentages in germination assays, an analytical model has been widely used in the last two decades which is based on the concept of thermal time. This article discusses the conceptual basis and provides procedures for applying the thermal-time model in germination studies by using the probit regression method, both at infra and supra-optimal temperatures.

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The main aspects of restoration, in various ecosystems, are here discussed, by means of a bibliographic analysis of the last twenty-eight years. The main concepts, research themes and target ecosystems are also described.

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This article aims to investigate the abbreviations used on chats by web-surfers between 15 and 20 years old. The material consists of two virtual conversations of about 60 minutes each. We believe that this linguistic process occurs due to the physical distance that separates affectively the web-surfers by modifying already said utterances in written practices characterized by short time of interaction. This abbreviation process, known as a characteristic of the so called internetês, is not considered as a simple attempt to cut the words, but as a resource that presents linguistics' regularity. Therefore, the theory of phonological syllable is used as a tool in order to verify the process that forms possible abbreviations used on chats. It is believed that, based on the study of the syllable structure, the choice of the graphemes abbreviation may be assessed based on the writing heterogeneity, since the writer might not only use oral/spoken practices but also literate/written ones so as to produce utterances that emerge in the contemporaneity.

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Metamafic orthoderivate rocks, characterized by MORB signatures and paleoproterozoic ages occur in Cajamar region central east part of São Paulo State, Brazil. They are associated to philites, metasandstones and metalimestones of São Roque Group volcanosedimentary sequence, Southeastern portion of the Ribeira Belt. For the metamafic rocks the assemblage of metamorphic peak is represented by actinolitealbite- epidote-chlorite typical of regional metamorphism, greenschist facies. For a good characterization of P and T parameters of metamorphism microprobe analyses of main minerals were performed. Metamorphism did not destroy completely the primary mineralogy of original basalt and microgabbro, and augite crystals are registered in many samples, preserved together with metamorphic assemblage, and possibly indicate that the igneous temperatures of crystallization are between 900 and 1.100°C. Textures of mineral equilibrium for the peak paragenesis are not always present in the studied samples. It may be partially caused by the superposition of retrometamorphic events that is a consequence of regional shearing process. Where the equilibrium is reached, chiefly in the occurrences in the south of the area temperature and pressure determinations indicate values close to 487 ± 42°C and 8,2 ± 2.0 kbar, respectively. Other values for P and T lower than that of the peak were also obtained in central and north portion of the area and they are: 450 ± 68°C for T e 4.7 kbar for P and 315 ± 26°C for T and 3.0 kbar for P and may indicate that the mineral equilibrium was not reached in these samples or that they represent the retrometamorphic event. As a concluding remark considering the metamorphic P-T path now obtained one can say that the exhumation process in this area occurred by isothermal decompression.

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Landfill is an engineering work that aims at to accommodate residues in the smallest possible space in the soil, with minimum damages to the environment and the public health. One in the constructive forms of a controlled landfill is the excavation of ditches with appropriate dimensions, for disposition of solid residues without compactation or impermeabilization. Liquid effluents generated for similar volumes of residues, disposed in ditches with ages different from closing, it should result in physical and chemical alterations you correlated at the time of residence materials. With base in this hypothesis, measures of electric resistivity were accomplished through the of Eletrical Resistivity geophysical method, on residues ditches closed annually between 12/2001 and 12/2007, localized in control landfill of the Cordeirópolis city (SP). The leachate is a liquid effluent generated by the decomposition of organic matter and characterized by high content in total dissolved solids, whose interaction with geological environment results in alterations in terms of electrical resistivity susceptible to detection for the geophysical instrumental. The results suggest a resistivity reduction for leachate percolation produced for ditches recently and increase progressive of the resistivity for older ditches. The statistical comparative analysis with reference values for the area suggests ages of the finish production and percolation leachate for soil and rock below the ditches.

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The rambutan (Nephelium lappaceum) is an exotic fruit with great market potential in Brazil. However, there are few available informations about plants with potential for cultivation, because great morphologic variation is observed among plants and for consequence, little uniformity in the orchards and in the fruits. This research had for objective to evaluate the genetic diversity of a collection of rambutan plants obtained by seeds through morfo-chemical analyses of plants and fruits and by fAFLP molecular markers, to indication of promising materials to be used in new plantings of the culture in the São Paulo State. Was verified that both markers, morphologic and molecular, were efficient in the distinction of varieties, showing the presence of genetic variability among the plants of this study. Was also verified that the materials A51 and B03 presented a larger group of desirable characteristics for new cultivations of the fruitful.

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Ceraeochrysa paraguaria do not has its life history well known, despite its description do not be recent. The present work aimed to evaluate morphometric aspects of C. paraguaria larvae were feeding on Diatraea saccharalis, Sitotroga cerealella e Anagasta kuehniella eggs with the objective to determine the mandibule length, head capsule length, torax + head length, and larvae weight. By the results it was possible to conclude: to the morphometrical parameters, only larvae weight was influenced by the food consumed by the predator, being the nymphal development shorter.

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Data set of 17.767 weight records of 4.210 Santa Inês lambs were used aiming to evaluate the importance of the inclusion of the maternal effect in the model to estimate components of (Co) variance and resulting genetic parameters for the growth curve through random regression models. The fixed and random regressions were fitted using Legendre Polynomials of order three, being fit four models that differed in relation to the inclusion of the additive genetic and permanent environmental maternal effects. Considerable increase was observed in Log L and decrease in the criteria AIC and BIC when the maternal effect was included (genetic or permanent environmental), evidencing its importance. The maternal genetic effect explained larger proportion of the phenotypic variance than the maternal permanent environmental along the growth curve. The direct additive genetic variance was inflated by maternal effect, when this last one was not considered in the analysis model, reflecting the same behavior in the heritabilities. The maternal permanent environmental effect contributed to maternal variance, as well as, it inflated maternal genetic variance, when it was not considered in the model. Similar behavior was verified with maternal heritability. The correlation estimated for the four models hardly differed in function of maternal effect. The maternal effect should be considered in the genetic studies of the growth curve of Santa Inês sheep.

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With the objective to know the electromyographic activity normal parameters of the deltoid (anterior portion) and pectoralis major (clavicular portion) muscles in the different modalities of military press exercises with middle grip, we analyzed 24 male volunteers using a two-channel electromyograph TECA TE 4, and Hewllet Packard surface electrodes. It was observed high inactivity levels for PMC in almost all the modalities and the concentration in the active cases, mainly, in the weak potential, while DA presented very high levels of much strong action potentials in all the modalities assessed.

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The deltoid (anterior portion) and pectoralis major (clavicular portion) were evaluated in several execution ways of military press exercises with open and middle grips in order to know their behavior pattern. It was analyzed 24 male volunteers, using a 2-channel TECA TE4 electromyograph and Hewllet Packard surface electrodes. It was observed that the execution variation with open and middle grips does not present any significant difference as for the demanding level neither for the pectoralis major muscle nor the deltoid muscle.

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This paper presents the results of the longitudinal profile analysis and the application of gradient index (RDE) in the Patos River, a tributary of the Ivaí River basin, PR. The goal is identify and quantify the anomalous zones along river course concerning their genesis - activity neotectonic or/and lithological imposition. The Patos River has a length of 127 km and a relief amplitude of 660 m, The occurrence of an important knickpoint in the middle course the Patos River can be divided into two stretches. Of the 22 sections measured, 10 were considered anomalous, distributed in both upper and lower course. In the upper course, over a basaltic bedrock of the Serra Geral Formation the RDE values are lower than those in the lower course, where river flows over sedimentary rocks of the Terezina Formation. The 2 nd order anomalies are related to lithological changes, relief alignments and channel confluences - as in the case of São João River. The 1st order anomalies are linked to differences in rock resistance associated with structural control, which provides the formation of waterfalls.

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This paper evaluates the behavior of suspended sediment load of the river Ivaí over a period of 32 years measured by the station further downstream the river (Novo Porto Taquara). The most suitable parameters for this assessment were the annual discharge of suspended sediment and water obtained from SUDERSA. The relationship between the concentration of suspended sediment and discharge of water had not a very good correlation (R 2 = 0,56) and hysteresis effect is quite clear. The justification for this behavior is given by the heterogeneity of the hydrological regime and basin occupation. There were no significant changes in annual flows which have remained the same during the study period. Already the discharge of suspended sediment showed a small gradual decline in which the end of the period (2007), the river carries less than 0.65 Mton at the beginning (1977). This reduction in suspended sediment transported is probably due to changes in soil management for agriculture.

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The Nabileque fluvial fan is a Quaternary depositional system located along the southwestern border of the Pantanal, covering an area of approximately 9,100 km 2. It is a peculiar alluvial system because it is not associated with inflow from adjacent plateaus. The Nabileque megafan is formed by the Paraguay River at the exit of the Pantanal wetland, coalescing with the Pilcomayo megafan of the Chaco basin. A geomorphological zonation analysis was performed making use of remote sensing data with field verification. Most of the area is a vast alluvial plain made of Pleistocene deposits, whose surface is marked by the presence of an intricate network of distributary paleochannels. Areas blanketed by Pleistocene deposits are dissected by erosional streams and subject to frequent flooding events. The Paraguay River flows in a meander belt constrained by NE fractures associated with the Transbrasiliano Lineament, but deflects towards the SSE after the Negro River confluence composing the system's peripheral drainage. An abandoned meander belt is preserved within a remarkable N-S incised-valley that is interpreted as the ancient Paraguay River course. Processes of avulsion and river capture are suggested to explain the observed changes of the river course. The Nabileque River is an underfit stream within the incised-valley, cutting paleomeanders and point bars of the previous Paraguay River course.