452 resultados para Afinidade


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The nonionic surfactants are composed of substances whose molecules in solution, does not ionize. The solubility of these surfactants in water due to the presence of functional groups that have strong affinity for water. When these surfactants are heated is the formation of two liquid phases, evidenced by the phenomenon of turbidity. This study was aimed to determine the experimental temperature and turbidity nonilfenolpoliethoxyled subsequently perform a thermodynamic modeling, considering the models of Flory-Huggins and the empirical solid-liquid equilibrium (SLE). The method used for determining the turbidity point was the visual method (Inoue et al., 2008). The experimental methodology consisted of preparing synthetic solutions of 0,25%, 0,5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12,5%, 15%, 17% and 20% by weight of surfactant. The nonionic surfactants used according to their degree of ethoxylation (9.5, 10, 11, 12 and 13). During the experiments the solutions were homogenized and the bath temperature was gradually increased while the turbidity of the solution temperature was checked visually Inoue et al. (2003). These temperature data of turbidity were used to feed the models evaluated and obtain thermodynamic parameters for systems of surfactants nonilfenolpoliethoxyled. Then the models can be used in phase separation processes, facilitating the extraction of organic solvents, therefore serve as quantitative and qualitative parameters. It was observed that the solidliquid equilibrium model (ESL) was best represented the experimental data.

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This dissertation aims the development of an experimental device to determine quantitatively the content of benzene, toluene and xylenes (BTX) in the atmosphere. BTX are extremely volatile solvents, and therefore play an important role in atmospheric chemistry, being precursors in the tropospheric ozone formation. In this work a BTX new standard gas was produced in nitrogen for stagnant systems. The aim of this dissertation is to develop a new method, simple and cheaper, to quantify and monitor BTX in air using solid phase microextraction/ gas chromatography/mass spectrometry (SPME/CG/MS). The features of the calibration method proposed are presented in this dissertation. SPME sampling was carried out under non-equilibrium conditions using a Carboxen/PDMS fiber exposed for 10 min standard gas mixtures. It is observed that the main parameters that affect the extraction process are sampling time and concentration. The results of the BTX multicomponent system studied have shown a linear and a nonlinear range. In the non-linear range, it is remarkable the effect of competition by selective adsorption with the following affinity order p-xylene > toluene > benzene. This behavior represents a limitation of the method, however being in accordance with the literature. Furthermore, this behavior does not prevent the application of the technique out of the non-linear region to quantify the BTX contents in the atmosphere.

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The generation of effluent from the finishing process in textile industry is a serious environmental problem and turned into an object of study in several scientific papers. Contamination with dyes and the presences of substances that are toxic to the environment characterize this difficult treatment effluent. Several processes have already been evaluated to remove and even degrade such pollutants are examples: coagulation-flocculation, biological treatment and advanced oxidative processes, but not yet sufficient to enable the recovery of dye or at least of the recovery agent. An alternative to this problem is the cloud point extraction that involves the application of nonionic surfactants at temperatures above the cloud point, making the water a weak solvent to the surfactant, providing the agglomeration of those molecules around the dyes molecules by affinity with the organic phase. After that, the formation of two phases occurred: the diluted one, poor in dye and surfactant, and the other one, coacervate, with higher concentrations of dye and surfactants than the other one. The later use of the coacervate as a dye and surfactant recycle shows the technical and economic viability of this process. In this paper, the cloud point extraction is used to remove the dye Reactive Blue from the water, using nonionic surfactant nonyl phenol with 9,5 etoxilations. The aim is to solubilize the dye molecules in surfactant, varying the concentration and temperature to study its effects. Evaluating the dye concentration in dilute phase after extraction, it is possible to analyze thermodynamic variables, build Langmuir isotherms, determine the behavior of the coacervate volume for a surfactant concentration and temperature, the distribution coefficient and the dye removal efficiency. The concentration of surfactant proved itself to be crucial to the success of the treatment. The results of removal efficiency reached values of 91,38%, 90,69%, 89,58%, 87,22% and 84,18% to temperatures of 65,0, 67,5, 70,0, 72,5 and 75,0°C, respectively, showing that the cloud point extraction is an efficient alternative for the treatment of wastewater containing Reactive Blue

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FUNDAMENTO: A hipertensão arterial é uma desordem caracterizada por alterações relevantes no tecido ósseo. O alendronato sódico tem indicação no tratamento de doenças ósseas, por causa de sua afinidade pela hidroxiapatita, inibindo as reabsorções ósseas. OBJETIVO: Analisar a ação local do alendronato sódico na reparação óssea de ratos espontaneamente hipertensos (SHR). MÉTODOS: Um defeito ósseo foi criado no fêmur esquerdo de 80 ratos. de acordo com o material utilizado no local, criaram-se quatro grupos: controle (C), amido (Am), alendronato 1 mol (A1) e alendronato 2 mol (A2). Após 7 e 21 dias, os animais foram sacrificados. Foram realizadas análises histológicas e histomorfométricas e os dados foram submetidos a análise de variância (ANOVA) e teste de Tukey (5%). RESULTADOS: Aos 7 dias, observou-se, na área do defeito, tecido conjuntivo com hemorragia e inflamação em todos os grupos. Alguns apresentavam matriz osteóide. Os grupos A1 e A2 apresentaram, ainda, uma rede de fibrina. Aos 21 dias, as trabéculas ósseas fechavam praticamente a extensão do defeito nos grupos C e Am. No grupo A1 de animais machos, observaram-se trabéculas que se irradiavam do canal medular até a área do defeito. Nos grupos A1 e A2, constatou-se apenas a presença de tecido conjuntivo com mínima deposição de osteóide. Um achado histológico marcante foi a formação de tecido ósseo extracortical subperiosteal nos animais dos grupos A1 e A2. CONCLUSÃO: Concluiu-se que a administração do alendronato sódico não contribuiu para o reparo ósseo nos ratos SHR, mas possivelmente tenha sido responsável pelas formações ósseas extracorticais observadas.

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This thesis endorses the interpretation that in Plato`s Republic the argument made by Thrasymachus in which justice is the convenience of the most powerful one is implicitly accepted by Socrates. Although Thrasymachus´ discussion does not show any similarity with the argument of Socrates, it proposes a sarcastic and ironic comment on political life. Socrates accepts this comment to develop a more refined notion of the category of the most powerful ones. While Thrasymachus assumes that the convenience of the most powerful ones includes the power to subordinate all and everything to their individual pleasures, Socrates admits that the most powerful ones are defined only by their characteristic of being able to hold power in perpetuity. In this context, the main theme of The Republic is that the harmony between the functional classes of the city is convenient for perpetual power. For preservation of harmony, the functional class of the most powerful considers the convenience of forsaking a possible monopoly on pleasure towards a redistribution that promotes harmony, which also makes it convenient for the other classes. Thus, we can explicitly say that the most powerful ones believe in a sense of justice as convenience for everyone, but implicitly believe only in the argument that justice is what is convenient for themselves. Since convenience is what promotes harmony between functional classes, it becomes convenient to Socrates to believe that the understanding justice that the most powerful ones have is not publicly disclosed. The notion that all the speculation of the dialogue between the characters cannot be true, but, at best, only plausible and convenient is also part of the central argument in The Republic. Socrates needs to modify the nature of the functional classes through a targeted program of sexual reproduction and a program of ideological indoctrination so that the proposal to promote harmony through the elements of the city, declaring that justice is in favor of the weakest becomes a more plausible and convenient speech. To make the new system more plausible, Socrates develops a metaphysics based on the mathematical notion of harmony, such metaphysics serving the official rhetoric of the political regime presented by Socrates

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The segmentation of an image aims to subdivide it into constituent regions or objects that have some relevant semantic content. This subdivision can also be applied to videos. However, in these cases, the objects appear in various frames that compose the videos. The task of segmenting an image becomes more complex when they are composed of objects that are defined by textural features, where the color information alone is not a good descriptor of the image. Fuzzy Segmentation is a region-growing segmentation algorithm that uses affinity functions in order to assign to each element in an image a grade of membership for each object (between 0 and 1). This work presents a modification of the Fuzzy Segmentation algorithm, for the purpose of improving the temporal and spatial complexity. The algorithm was adapted to segmenting color videos, treating them as 3D volume. In order to perform segmentation in videos, conventional color model or a hybrid model obtained by a method for choosing the best channels were used. The Fuzzy Segmentation algorithm was also applied to texture segmentation by using adaptive affinity functions defined for each object texture. Two types of affinity functions were used, one defined using the normal (or Gaussian) probability distribution and the other using the Skew Divergence. This latter, a Kullback-Leibler Divergence variation, is a measure of the difference between two probability distributions. Finally, the algorithm was tested in somes videos and also in texture mosaic images composed by images of the Brodatz album

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Studies on Brazilian biodiversity are still very few and can observe the difference of knowledge between the different regions of the country. This affirmation can be verified in the investigation to identify the rare species in Brazil and the key biodiversity areas (ACBs). In that study were identified for Brasil 2.256 rare species and 752 ACBs. The Rio Grande do Norte (RN) was the only Brazilian state that has not been identified any rare species and no ACBs, possibly due to the lack of floristic studies in this state. A particular area was selected for this study: an area of ecological tension with savanna physiognomy in Rio do Fogo, RN. This savanna community is represented in RN in a fragment and immersed in restinga and caatinga and was identified and described only through of radar imagens there are no studies to date in loco . We have prepared the following questions about this community savanna: 1) The region delimited and described by through of radar images by the RADAMBRASIL, 1976, can be associated of the Cerrado, in terms of floristic ?; 2) What is the floristic composition of this area? This area includes rare species, endemic or endangered? 3) What is the geographical and phytogeographical distribution of plant species registered in this area? 4) Those plant species registered are endemic or have affinity with other areas phytoecological Brazilian? To answer these questions we performed a floristic inventory of the August 2007 to September/2009. The results are presented in two chapters (manuscripts). The first chapter, titled "The Savannah Rio Grande do Norte: floristic links with other plant formations in the Northeast and Center-West Brazil" was submitted to the Revista Brasileira de Botância. Chapter 1 discusses the phytogeographical distribution of the species, by comparing floristic studies conducted in the Cerrado, Caatinga and Restinga in the Northeast and Cerrado of the Central Brazil. The analysis of data of this study and compilation with other studies indicated that: i) the record of 94 plant species; ii) of total species, about 64% are associated with the Cerrado, the second specialized bibliography, and about 78% as the List of Species of Flora of Brazil. However, about 73% of total species (94) are also distributed in the Caatinga, the Atlantic forest 64%, the Amazon forest 64%, the Pantanal 15% and the Pampa 12%. Floristically the data show that the community studied is influenced by other floras, has a structure where grasses dominate and also because of his appearance the same savanna then be classified as a Savana gramíneo-lenhosa do tabuleiro . Chapter 2, titled "Considerations on the flora of a savanna community in Rio Grande do Norte, northeastern Brazil: Subsidy key area for conservation" was submitted to the Revista Natureza e Conservação. This has the objective of improve the knowledge of flora of Rio Grande do Norte and to identify possible rare species and consequently increase the key areas of biodiversity in Brazil. The data indicated that: i) of 94 species registered in the study area, 40 were new records for the Rio Grande do Norte state; ii) These citations to unpublished state, Stylosanthes montevidensis Vogel (Fabaceae) and Aristida laevis (Nees) Kunth (Poaceae) are indicated for the first time to the Northeast of Brazil; iii) are registered in the area 24 species endemic to Brazil and 63 non-endemic; iv) Aspilia procumbens Baker (Asteraceae) registered in the area is considered a restricted species and micro endemic Rio Grande do Norte, ie rare species; v) Aspilia procumbens is also cited in the category of critically endangered species and Stilpnopappus cearensis Hubber (Asteraceae) a species vulnerable to extinction. This study shows a new area phytoecological in Rio Grande do Norte and indicates the area's potential to contribute with the sites of global significance for biodiversity conservation, either locally, regionally and nationally. This will certainly contribute to respond some targets set by the Global Strategy for Plant Conservation and the Convention on Biological Diversity such as the inventory of vegetal diversity in a region with little collection, which will provide data that contributes to questions and themes related to biodiversity.

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This thesis aims to advance in the geological knowledge of the region comprising the Piancó-Alto Brígida (TPAB) and Alto pajeú (TAP) terranes, in the Transversal Zone Domain (Borborema Province, NE Brazil), with the main objective of understanding the geodynamic evolution and the structural framework of these units. To reach this objective, and besides field work and interpretation of traditional aerial photographs, other tools were employed like of remote sensing products (Landsat 7 ETM+, aeroradiometrics, aeromagnetics and topographical images), lithogeochemical (whole rock) analyses and geochronological dating (U-Pb in zircon), besides integration with literature data. In the area, several precambrian geological units outcrop, represented in the TAP by the paleoproterozoic Serra Talhada and Afogados da Ingazeira complexes, Riacho Gravatá Complex (metavolcano-sedimentary sequence of Stenian-Tonian age) and Cariris Velhos orthogneisses (of Tonian age). The TPAB comprises the Santana do Garrote (lower unit) and Serra do Olho d'Água (upper unit) formations of the Cachoeirinha Group (Neoproterozoic III), besides the Piancó orthogneisses and Bom Jesus paragneisses; the latter correspond to an older (basement ?) block and a possible high grade equivalent of the Cachoeirinha Group (or Seridó Group ?), respectively. Several Brasiliano-age plutons occur in both terranes.The aeromagnetic data show the continuity, at depth, of the main shear zones mapped in the region. The Patos, Pernambuco, Boqueirão dos Cochos, Serra do Caboclo, Afogados da Ingazeira/Jabitacá and Congo-Cruzeiro do Nordeste shear zones reach depths greater than to 6-16 km. The aeromagnetic signature of other shear zones, like the Juru one, suggests that these structures correspond to shallower crustal features. The satellite images (Landsat 7 ETM+) and aerogamaspectrometric images discriminate different geological units, contributing to the mapping of the structural framework of the region. The Serra do Caboclo Shear Zone was characterized as the boundary/suture between the TPAB and TAP. This structure is an outstanding, pervasive feature that separates contrasting geological units, such as the Neoproterozoic III Cachoeirinha Group in the TPAB and the Riacho Gravatá Complex and the Cariris Velhos metaplutonics, of Stenian-Tonian age, in the TAP. Occupying different blocks, these units are not found in authoctonous relations, like unconformities and intrusive contacts. Concerning the Cariris Velhos (ca. 1,0 Ga old) event is recorded by radiometric ages of the Riacho Gravatá Complex metavolcanics and intrusive augen and orthogneisses, all of them displaying geochemical affinities of arc or collisional settings. A structural signature of this event was not recorded in the region, possibly due to its low grade/low strain style, obliterated by the overprinting of younger, higher grade/high strain Brasiliano-age fabrics.The first tectonic event (D1) observed in the Cariris Velhos lithotypes presents contractional kinematics with transport to the NW. Neoproterozoic III geochronologic dates, obtained in late-D1 granitoids, imply a Brasiliano age (ca. 610-600 Ma) for this deformation event. The second tectonic event (D2) characterized in the region corresponds to the Brasiliano transcurrent kinematics of the outstanding shear zones and associated granitoid plutons. The geochronological (U-Pb in zircon) data obtained during this thesis also confirms the occurrence of the Cariris Velhos magmatic suite in the TAP, as well as the Neoproterozoic III age to the Cachoeirinha Group in the TPAB. The TAP (Riacho Gravatá Complex, augen and orthogneisses) is interpreted as a continental arc possibly accreted to a microcontinent during the Cariris Velhos (Stenian-Tonian) event. Later on, this terrane collided with the TPAB at the beginning of the Brasiliano orogeny (D1 contractional deformation), and both domins were reworked by the transcurrent shear deformation of the D2 event

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The area studied is located on the north-easternmost portion of the Borborema Province, on the so-called São José de Campestre Massif, States of RN and PB, Northeast Brazil. Field relations and petrographic, geochemical and isotope data permitted the separation of five suites of plutonic rocks: alkali-feldspar granite (Caxexa Pluton), which constitutes the main subject of this dissertation, amphibole-biotite granite (Cabeçudo Pluton), biotite microgranite, gabbronorite to monzonite (Basic to Intermediate Suite) and aluminous granitoid. The Caxexa Pluton is laterally associated to the Remígio Pocinhos Shear Zone, with its emplacement along the mylonitic contact between the gneissic basement and the micashists. This pluton corresponds to a syntectonic intrusion elongated in the N-S direction, with about 50 km2 of outcropping surface. It is composed exclusively of alkali-feldspar granites, having clinopyroxene (aegirine-augite and hedenbergite), andradite-rich garnet, sphene and magnetite. It is classified geochemically as high silica rocks (>70 % wt), metaluminous to slightly peraluminous (normative corindon < 1%), with high total alkalis (>10% wt), Sr, iron number (#Fe=90-98) and agpaitic index (0.86-1.00), and positive europium anomaly. The Cabeçudo Pluton is composed of porphyritic rocks, commonly containing basic to intermediate magmatic enclaves often with mingling and mixing textures. Petrographically, it presents k-feldspar and plagioclase phenocrysts as the essential minerals, besides the accessories amphibole, biotite, sphene and magnetite. It is metaluminous and shows characteristics transitional between the calc-alkaline and alkaline series (or monzonitic subalkaline). Its REE content is greater than those ones of the Caxexa Pluton and biotite microgranite, and all spectra have negative europium anomalies. The biotite microgranites occur mainly on the central and eastern portion of the mapped area, as dykes and sheets with decimetric thickness, hosted principally in orthogneisses and micashists. Their field relationships as regards the Caxexa and Cabeçudo plutons suggested that they are late-tectonic intrusions. They are typically biotite granites, having also sphene, amphibole, allanite, opaques and zircon in the accessory assemblage. Geochemically they can be distinguished from the porphyritic types because the biotite microgranites are more evolved, peraluminous, and have more fractionated REE spectra. The Basic to Intermediate rocks form a volumetrically expressive elliptical, kilometric scale body on the Southeast, as well as sheets in micashists. They are classified as gabbronorites to monzonites, with the two pyroxenes and biotite, besides subordinated amounts of amphibole, sphene, ilmenite and allanite. These rocks do not show a well-defined geochemical trend, however they may possibly represent a monzonitic (shoshonitic) series. Their REE spectra have negative europium anomalies and REE contents greater than the other suites. The aluminous granitoids are volumetrically restricted, and have been observed in close association with migmatised micashists bordering the gabbronorite pluton. They are composed of almandine-rich garnet, andalusite, biotite and muscovite, and are akin to the peraluminous suites. Rb-Sr (whole rock) and Sm-Nd (whole-rock and mineral) isotopes furnished a minimum estimate of the crystallization (578±14 Ma) and the final resetting age of the Rb-Sr system (536±4 Ma) in the Caxexa Pluton. The aluminous granitoid has a Sm-Nd garnet age similar to that one of the Caxexa Pluton, that is 574±67 Ma. The strong interaction of shear bands and pegmatite dykes favoured the opening of the Rb-Sr system for the Caxexa Pluton and biotite microgranite. The amphibole-plagioclase geothermometer and the Al-in amphibole geobarometer indicate minimum conditions of 560°C and 7 kbar for the Cabeçudo Pluton, 730°C and 6 kbar for the microgranite and 743°C and 5 kbar for the basic to intermediate suite. The Zr saturation geothermometer reveals temperatures of respectively 855°C, 812°C and 957°C for those suites, whereas the Caxexa Pluton shows temperatures of around 757°C. The Caxexa, Cabeçudo and microgranites suites crystallized under high fO2 (presence of magnetite). On the other hand, the occurrence of ilmenite suggests less oxidant conditions in the basic to intermediate suite. Field relations demonstrate the intrusive character of the granitoids into a tectonically relatively stable continental crust. This is corroborated by petrographic and geochemical data, which suggest a late- or post-collisional tectonic context. It follows that the generation and emplacement of those granitoid suites is related to the latest events of the Brasiliano orogeny. Finally, the relationships between eNd (600 Ma), TDM (Nd) and initial Sr isotope ratio (ISr) do not permit to define the precise sources of the granitoids. Nevertheless, trace element modelling and isotopic comparisons suggest the participation of the metasomatised mantle in the generation of these suites, probably modified by different degrees of crustal contamination. In this way, a metasomatised mantle would not be a particular characteristic of the Neoproterozoic lithosphere, but a remarkable feature of this portion of the Borborema Province since Archaean and Paleoproterozoic times.

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The Brasiliano Cycle in the Seridó Belt (NE Brazil) is regarded mostly as a crustal reworking event, characterized by transcurrent or transpressional shear zones which operated under high temperature and low pressure conditions. In the eastern domain of this belt- the so-called São José de Campestre Massif (SJCM), a transtensional deformation regime is evidenced by extensional components or structures associated to the strikeslip shear zones. The emplacement of the Neoproterozoic Brasiliano granitoids is strongly controled by these discontinuities. Located in the southern border of the SJCM, the Remígio-Pocinhos shear zone (RPSZ) displays, in its northern half, top to the SW extensional movement which progressively grade, towards its southern half, to a dextral strike-slip kinematics, defining a negative semi-flower structure. This shear zone is overprinted upon allocthonous metasediments of the Seridó Group and an older gneiss-migmatite complex, both of which containing metamorphic parageneses from high amphibolite to granulite facies (the latter restricted to the strike-slip zone), defining the peak conditions of deformation. Several granitoid plutons are found along this structure, emplaced coeval with the shearing event. Individually, such bodies do not exceed 30 km2 in outcropping area and are essentially parallel to the trend of the shear zone. Petrographic, textural and geochemical data allow to recognize five different granitoid suites along the RPSZ: porphyritic granites (Serra da Boa Vista and Jandaíra), alkaline granites (Serra do Algodão and Serra do Boqueirão) and medium to coarse-grained granites (Olivedos) as major plutons, while microgranite and aluminous leucogranite sheets occur as minor intrusions. The porphyritic granites are surrounded by metasediments and present sigmoidal or en cornue shapes parallel to the trend of the RPSZ, corroborating the dextral kinematics. Basic to intermediate igneous enclaves are commonly associated to these bodies, frequently displaying mingling textures with the host granitoids. Compositionally these plutons are made up by titanite-biotite monzogranites bearing amphibole and magnetite; they are peraluminous and show affinities to the monzonitic, subalkaline series. Peraluminous, ilmenite-bearing biotite monzogranites and titanite-biotite monzogranites correspond, respectivally, to the Olivedos pluton and the microgranites. The Olivedos body is hosted by metasediments, while the microgranites intrude the gneiss-migmatite complex. Being highly evolved rocks, samples from these granites plot in the crustal melt fields in discrimination diagrams. Nevertheless, their subtle alignment also looks consistent with a monzonitic, subalkaline affinity. These chemical parameters make them closer to the I-type granites. Alkaline, clearly syntectonic granites are also recognized along the RPSZ. The Serra do Algodão and Serra do Boqueirão bodies display elongated shapes parallel to the mylonite belt which runs between the northern, extensional domain and the southern strike-slip zone. The Serra do Algodão pluton shows a characteristic isoclinal fold shape structure. Compositionally they encompass aegirine-augite alkali-feldspar granites and quartz-bearing alkaline syenite bearing garnet (andradite) and magnetite plus ilmenite as opaque phases. These rocks vary from meta to peraluminous, being correlated to the A-type granites. Aluminous leucogranites bearing biotite + muscovite ± sillimanite ± garnet (S-type granites) are frequent but not volumetrically important along the RPSZ. These sheet-like bodies may be folded or boudinaged, representing partial melts extracted from the metasediments during the shear zone development. Whole-rock Rb-Sr isotope studies point to a minimum 554��10 Ma age for the crystalization of the porphyritic granites. The alkaline granites and the Olivedos granite produced ca. 530 Ma isochrons which look too young; such values probably represent the closure of the Rb-Sr radiometric clock after crystallization and deformation of the plutons, at least 575 Ma ago (Souza et al. 1998). The porphyritic and the alkaline granites crystallized under high oxygen fugacity conditions, as shown by the presence of both magnetite and hematite in these rocks. The presence of ilmenite in the Olivedos pluton suggests less oxidizing conditions. Amphibole and amphibole-plagioclase thermobarometers point to minimum conditions, around 750°C and 6 Kbars, for the crystallization of the porphyritic granites. The zirconium geothermometer indicates higher temperatures, in the order of 800°C, for the porphyritic granites, and 780°C for the Olivedos pluton. Such values agree with the thermobarometric data optained for the country rocks (5,7 Kbar and 765°C; Souza et al. 1998). The geochemical and isotope data set point to a lower crustal source for the porphyritic and the alkaline granites. Granulite facies quartz diorite to tonalite gneisses, belonging or akin to the gneiss-migmatite complex, probably dominate in the source regions. In the case of the alkaline rocks, subordinate contributions of mantle material may be present either as a mixing magma or as a previously added component to the source region. Tonalite to granodiorite gneisses, with some metasedimentary contribution, may be envisaged for the Olivedos granite. The diversity of granitoid rocks along the RPSZ is explained by its lithospheric dimension, allowing magma extraction at different levels, from the middle to lower crust down to the mantle. The presence of basic to intermediate enclaves, associated to the porphyritic granites, confirm the participation of mantle components in the magma extraction system along the RPSZ. This mega-structure is part of the network of Brasiliano-age shear zones, activated by continental collision and terrane welding processes at the end of the Neoproterozoic

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This dissertation describes the igneous suites of the Japi granitoid pluton, intrusive in the Paleoproterozoic gneiss-migmatite complex of the eastern domain of the Seridó Belt, northeastern Brazil. Field relations show that the pluton is affected by strong deformation associated to the Brasiliano orogeny (known as the D3 phase) , with a NW-trending extensionalleft-hand senestral shear zone (the Japi Shear Zone, JSZ) bordering the intrusive body to the west. Four plutonic suites are found in the main pluton and as satellyte intrusions, besides Iate pegmatite and pink leucogranites. An alkaline granitoid suite, dominated by syenogranites bearing sodic augite (and subordinate hornblende), define a main elliptical intrusion. In its northern part, this intrusion is made up by concentric sheets, contrasting with a smaller rounded stock to the south. These granites display a pervasive solid-state S>L fabric developed under high T conditions, characterized by plastic deformation of quartz and feldspar. It is especially, developed along the border of the pluton, with inward dips. A regular magmatic layering is present sometimes, parallel to the tectonic foliation. The syntectonic emplacement as regards to the Brasiliano (D3) event is indicated by the common occurrence of dykes and sheets along transtensional or extensional sites of the major structure. Field relations attest to the early emplacement of the alkaline granites as regards to the other suites. A basic-to-intermediate suite occurs as a western satellyte body and occupying the southern tail of the main alkaline pluton. It comprises a wide variety of compositional terms, including primitive gabbros and gabbro-norites, differentiated to monzonitic intermediate facies containing amphibole and biotite as their main mafic phases. These rocks display transitional high-K calc-alkaline to shoshonitic affinities. Porphyritic monzogranite suítes commonly occur as dykes and minor intrusives, isolated or associated with the basic-tointermediate rocks. In the latter case, magma mingling and mixing features attest that these are contemporaneous igneous suites. These granites show K-feldspar phenocrysts and a hornblende+biotite+titanite assemblage, displaying subalkaline/monzonitic geochemical affinities. Both suites exhibit SL magmatic fabrics overprinting or transitional to solid-state D3 deformation related to the JSI. Chemical data clearly show that they are related to different parental magmas. Finally, a microgranite suite occurs along a few topographic ridges paralell to the JSI. It comprises dominantly granodiorites with a mineralogy similar to the one of the porphyritic granitoids. However, discriminant diagrams show their distinct calc-alkaline affinity. The granodiorites display an essencially magmatic fabric, even though an incipient D3 solid-state structure may be developed along the JSI. Intrusion relationships with the previous suites, as well as regards to the D3 structures, point to their Iate emplacement. All these suites are intrusive in a Paleoproterozoic, high-grade gneiss-migmatite complex affected by two previous deformation phases (D1, D2). The fabrics associated with these earlier events are folded and overprinted by the younger D3 structures along the JSZ. The younger deformation is characterized by NE-dipping foliations and N/NE-plunging stretching lineations. In the JSZ northern termination the foliation acquires an ENE orientation, containing a stretching lineation plunging to the south. Symmetric kinematic cri teria developed at this site confirms the transpressional termination of the JSZ, as also shown by orthorrombic quartz c-axis patterns. E-W-trending d extra I shear zones developed in the central part of the JSZ are interpreted as antithetic structures associated to the transtensional deformation along the JSZ. This is consistent with its extensional-transcurrent kinematics and a flat-and-ramp geometry at depth, as shown by gravimetric data. The lateral displacement of the negative residual Bouguer anomalies, as regards to the main outcropping alkaline pluton, may be modelized by other deeper-seated granite bodies. Based on numerical modelling it was possible to infer two distinct intrusion styles for the alkaline pluton. The calculated model values are consistent with an emplacement by sheeting for the northern body, as already suggested by satellyte imagery and field mapping. On the other hand, the results point to a transition towards a diapir-related style associated to the smaller. southern stock. This difference in intrusion styles may relate to intensity variations and transtensional sites of the shear deformation along the JSZ. Trace element and Sr and Nd isotopes of the alkaline granites are compatible with their derivation trom a more basic crustal source, as compared to the presently outcropping highgrade gneisses, with participation (or alternatively dominated by) of an enriched lithospheric mantle component. Like other igneous suites in the Seridó Belt, the high LlL contents and fractionated REE patterns of the basic rocks also point to an enriched mantle as the source for this kind of magmatism. Geochemical and isotope data are compatible with a lower crustal origin for the porphyritic granites. On the basis of the strong control of the JSZ on the emplacement of lower crustal (porphyritic and alkaline granites) or lithospheric mantle (basic rocks, alkaline granites or a component of them) magmas, one may infer a deep root for this structure, bearing an important role in magma extraction, transport and emplacement in the Japi region, eastern domain of the Seridó Belt

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The of Serrinha plutonic suite, northeastern portion of the Borborema Province (NE Brazil), is characterized by a voluminous and diversified magmatism of Neoproterozoic age, intrusive in the Archean to Paleoproterozoic gneissic-migmatitic basement of the São José de Campestre massif. Field relations and petrographic and geochemical data allowed us to individualize different lithologic types among this plutonic suite, which is represented by intermediate to mafic enclaves, porphyritic diorites, porphyritic granitoids, porphyritic granodiorites, microporphyritic granites and dykes/sheets of microgranite. The intermediate-to-mafic enclaves occur associated with porphyritic granitoids, showing mixture textures. The porphyrytic diorites occur as isolated bodies, generally associated with intermediate-to-mafic enclaves and locally as enclaves within porphyritic granites. The granodiorites represent mixing between an intermediate to mafic magma with an acidic one. The micropophyritic granites occur as isolated small bodies, generally deformed, while the microgranite dykes/sheets crosscut all the previous granitoids. A U-Pb zircon age of 576 + 3 Ma was obtained for the Serrinha granite. This age is interpreted as age of the peak of the regional ductile deformational event (D3) and of the associated the E-W Rio Jacu shear zone, which control the emplacement of the Neoproterozoic syntectonic plutons. The porphyrytic granitoids show monzogranitic composition, transitional between peraluminous and metaluminous types, typically of the high potassium subalkaline-calc-alkaline series. The intermediate-to-mafic enclaves present vary from quartz diorite to tonalite/granodiorite, with metaluminous, shoshonitic affinity. The diorites are generally quartz-monzodiorite in composition, with metaluminous, subalkaline affinity. They display coarse-grained, inequigranular, porphyrytic texture, with predominance of plagioclase phenocrystals immersed in a matrix composed of biotite and pyroxenes. The microporphyrytic granites are essentially monzogranites of fine- to medium-grained texture, whereas microgranite dikes/sheets varying from monzogranites to syenogranites, with fine to media texture, equigranular. The diversified magmatism occurring at a relatively small surface associated with shear zones, suggests lithospheric dimensions for such structures, with magma extractions from different depths within the lower crust and upper mantle. The geological, geochemical and geochronological characteristics of the Serrinha plutonic suite suggest a pos-collisional geodynamic context for the Neoproterozoic magmatism. Thermobarometric data show emplacement conditions in the range 5-6 kbar (AlTamphibole) and 730-740°C (plagioclase-amphibole) for the porphyrytic granitoids (Serrinha body) and the intermediate-to-mafic enclaves

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Em meados da década de 50 iniciou-se o desenvolvimento da citometria de fluxo, tecnologia que permite verificar características físico-químicas de células ou partículas suspensas em meio fluido. Esta tecnologia utiliza anticorpos monoclonais marcados com fluorocromos como ferramenta de investigação em diversas análises e necessita de controles isotípicos para definição da região negativa (background). Estes controles são constituídos por imunoglobulinas de mesmo isotipo e fluorocromo dos anticorpos testes, sendo o isotiocianato de fluoresceína (FITC) o marcador fluorescente mais utilizado na conjugação de anticorpos. Os controles isotípicos têm como função definir a fluorescência inespecífica (células negativas) e as regiões fluorescentes (células positivas). No presente estudo foi selecionado anticorpo monoclonal murino (AcMm) dirigido contra antígeno eritrocitário canino, produzido no Laboratório de Anticorpos Monoclonais do Hemocentro de Botucatu, o qual reage positivamente com hemácias de cães, mas nunca com leucócitos humanos, tendo, portanto, potencial utilidade como controle negativo em citometria de fluxo. A purificação do AcMm da subclasse IgG1 foi feita por cromatografia de afinidade em Proteína-A Sepharose, e o controle da purificação realizado por eletroforese em géis de ágarose e poliacrilamida (SDS-PAGE). A imunoglobulina purificada foi conjugada ao FITC e filtrado em coluna de Sephadex G-25 para separação das proteínas marcadas e não-marcadas. O AcMm conjugado foi testado contra hemácias de cães, e o êxito da conjugação comprovado por testes de fluorescência, sendo a mediana de positividade de 94,70. Frente a leucócitos humanos a mediana de positividade foi 0,03 contra 0,50 dos reagentes comerciais. Os testes estatísticos não-paramétricos de Wilcoxon e correlação de Spearman comprovaram a eficiência e validam o controle isotípico produzido em comparação aos reagentes comerciais testados.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Com o objetivo de avaliar a variabilidade genética e as relações de afinidade entre dezenove populações de oito raças de milho (Zea mays L.) - as comerciais antigas Cateto Sulino, Cateto Sulino Grosso, Cateto Nortista e Canario de Ocho, e as raças indígenas Moroti, Lenha, Entrelaçado e Caingang - analisaram-se os seguintes sistemas enzimáticos: glutamato oxalacetato transaminase (GOT), esterase (EST) e malato desidrogenase (MDH). Observou-se maior semelhança entre as raças pertencentes a um mesmo grupo, mas as populações analisadas não se agruparam de acordo com as raças, classificadas anteriormente segundo caracteres morfológicos. Os sistemas enzimáticos utilizados não permitiram a caracterização individual de cada uma das raças analisadas. As indígenas apresentaram maior variabilidade do que as comerciais antigas quanto ao número de alelos por loco e à porcentagem de locos polimórficos.