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Search Results: 1 - 10 of 187788 matches for " Marcos Tadeu de Freitas;Pedrosa-Soares "
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Síntese sobre ofiolitos: evolu??o dos conceitos
Queiroga, Gláucia Nascimento;Suita, Marcos Tadeu de Freitas;Pedrosa-Soares, Ant?nio Carlos;Martins, Maximiliano de Souza;Pinheiro, Marco Aurélio Piacentini;
Rem: Revista Escola de Minas , 2012, DOI: 10.1590/S0370-44672012000100007
Abstract: ophiolites are fragments of the ancient oceanic lithosphere formed at constructive plate margins or transforming divergent plates. through extensive thrust faults, these bodies or part of them are emplaced into the continental crust, inside rock piles of orogenic belts, in solid state, but these bodies can be relatively warm. the possible environments which produce oceanic lithosphere include meso-oceanic ranges, basins related to juvenile island arcs and retro-arc basins. ophiolites of the phanerozoic age are abundant in orogenic belts around the world whilst precambrian oceanic remnants are less common and are distributed mainly in finland, canada, morocco, saudi arabia, egypt, russia, brazil and china. several registers of precambrian oceanic remnants of different ages were recognized in brazil. most of these bodies are situated in brazilian orogenic belts and they register the consumption of the neoproterozoic oceans. this paper aims to synthetize the main information about ophiolitic sequences, bringing a brief review of concepts and classifications along the 200-year use of this term.
Características geoquímicas da Suíte G1, arco magmático do Orógeno Ara?uaí, entre Governador Valadares e Ipanema, MG
Gon?alves, Leonardo E. da Silva;Alkmim, Fernando Flecha de;Pedrosa-Soares, Ant?nio Carlos;
Rem: Revista Escola de Minas , 2010, DOI: 10.1590/S0370-44672010000300006
Abstract: this article presents the results of a petrogenetic and geochemical study carried out for granitoid plutons of the g1 suite of the ara?uaí orogen, exposed in the region between governador valadares and ipanema (mg). the g1 suite comprises three distinct lithofacies, namely enderbitic-tonalitic, granodioritictonalitic and granitic, which show chemical characteristics similar to an expanded calc-alkaline, metaluminous to slightly peraluminous i-type assemblage. investigation results indicate that each individual g1 lithofacies represents an evolutionary stage of granitic magmatism, the enderbitic-tonalitic and granitic corresponding to the least and most differentiated components, respectively. together with the volcanic rocks of the rio doce group, the studied g1 rocks made up the magmatic arc of the ara?uaí orogen, developed on a continental margin between 630 and 585 ma.
Geometria e evolu??o do feixe de zonas de cisalhamento Manhua?u - Santa Margarida, Orógeno Ara?uaí, MG
Silva, Cláudio Maurício Teixeira da;Alkmim, Fernando Flecha;Pedrosa-Soares, Ant?nio Carlos;
Rem: Revista Escola de Minas , 2009, DOI: 10.1590/S0370-44672009000100005
Abstract: the n-s trending manhua?u-santa margarida shear zone system extends for ca. 300 km in eastern minas gerais. as one of the main structures of the crystalline core of the neoproterozoic ara?uaí orogen, the manhua?u-santa margarida system is made up of a series of ductile shear zones, which show a sigmoidal trace in map view. the northern segment of the system mainly consists of west-verging thrusts and subordinate dextral strike-slip shear zones. the central and southern segments are dominated by dextral strike-slip shear zones. the development of the manhua?u-santa margarida system occurs in four distinct neoproterozoic deformation phases. during the first phase, the system nucleated as a series of thrust shear zones, which remain preserved in the northern segment. during the second phase, the thrust zones experienced a clockwise rotation coupled with an intensive strike-slip reactivation, becoming vertical and ne-striking in the southern portion of the orogen. the third deformation phase generated normal-sense shear zones, observed only in the northern segment of the system. brittle deformation along wnw-striking fault zones and jointing are the manifestations of the fourth and youngest deformation phase. the southern segment of the manhua?u-santa margarida system, dominated by dextral strike-slip zones, rotates progressively to a ne orientation and merges with the structures of the northwestern segment of the ribeira belt. therefore, the structures of the southern termination of the manhua?u-santa margarida system are of the same age or slight older than the dextral strike-slip shear zones that characterize the tectonic grain of the northwestern portion of the ribeira belt.
Stratigraphy of the Lower Bambuí Group in the Arcos Region (MG): a Contribution from Boreholes
Matheus Kuchenbecker,Leonardo Lopes-Silva,Felipe Pimenta,Ant?nio Carlos Pedrosa-Soares
Geologia USP : Série Científica , 2011,
Abstract: This study presents the fi rst results of the sample analysis of two boreholes drilled in a quarry located in the Arcos region(MG). Petrographic analysis (macro- and microscopic observations) was performed and made possible to study in detailan approximately 175 meter-section, which shows the basement and 10 sedimentary units. The basement is represented bydark green to gray fi ne- to medium-grained granodiorite. At the base of the sedimentary sequence, Unit 1 is representedby a decimetric layer of polymictic diamictite and is overlain by the impure limestones of Unit 2. Unit 3 is carbonatic andcontains calcilutite and layers of carbonaceous shale. This unit gradually changes to Unit 4, which is composed of marland mudstone. Unit 5 is composed of a thick sequence of massive calcarenites, which begins to show lamellar layers andmicrobial structures in Unit 6. Unit 7 is similar to the previous one, but contains several intraclastic layers. The numberof lamellar layers decreases sharply, giving rise to a thick interval with considerable granulometric variations in Unit 8, which grades to the oolitic calcarenite of Unit 9. At the top of the sequence, Unit 10 is a thick package of stromatolitic dolarenite. Thisstratigraphic arrangement allows the identifi cation of progradational/retrogradational trends. The sedimentological features, especially those present in the basal portion, suggest that at least part of the carbonatic sequence could represent a cap carbonate, supporting a glacial origin for the diamictite. Other data also collected from the basal units suggest that changes occurred in the source area at the beginning of the fi lling of the basin.
Valor nutritivo do resíduo de própolis para frangos de corte
Santos, Asdrubal Viana dos;Teixeira, Ant?nio Soares;Rodrigues, Paulo Borges;Freitas, Rilke Tadeu Fonseca de;Guimar?es, Ant?nio Marcos;Giacometti, Renato Alberto;
Ciência e Agrotecnologia , 2003, DOI: 10.1590/S1413-70542003000500025
Abstract: two experiments were run at the poultry sector of the animal science department of the federal university of lavras (brazil) with the objective of determining the nutritive value of propollis residue for broiler feeding. in the first experiment, the metabolizable energy of propollis residue was determined. in this experiment, 16 adults fed with 2,500 ± 100 g of propollis were housed in a metabolism cage (sibbald and slinger, 1963). two rations with eight replicates, one bird each, after an adaptation period of three day period and feces collection for five days were utilized. the two rations were (i) reference ration based on corn and soybean meal and (ii) 80 % of the reference ration plus 20% of the propollis extraction residue. the value of apparent metabolizable energy was 941 kcal/kg dm. in addition, we found 20% crude protein, 27% ether extract, and 14% raw fiber. in the second experiment, the bird performance was evaluated by using five diets with 0, 3, 6, 9, and 12% of propollis extraction residue in a completely randomized performance design. the rations were isonutritive, with four replicates of males and four females, with 30 birds each, amounting to 1.200 birds, reared in 2 × 1.5-m boxes in a stonework house. in the first phase, 1 to 21 days, for the variable ration intake, there were no significant effects for residue levels and for level × gender interaction (p >0.05). nevertheless, there was a significant effect only for gender (p <0.01) and there was no interaction between levels and gender (p <0.05). weight gain worsened linearly when the residue levels in the ration were raised for both males and females, observing that in this period the addition of residue provided a growing linear feed conversion for males and females. in phase 1 to 42 days, for ration intake, there was a significant effect for gender (p<0.01) and for level × gender interaction (p <0.05), but there was no significant difference among females (p <0.05). there was a significant eff
Níveis de cálcio em ra es de frangos de corte na fase inicial suplementadas com fitase
Schoulten Neudi Artemio,Teixeira Ant?nio Soares,Freitas Rilke Tadeu Fonseca de,Bertechini Ant?nio Gilberto
Revista Brasileira de Zootecnia , 2003,
Abstract: Com o objetivo de avaliar níveis de cálcio em ra es suplementados com enzima fitase para frangos de 1 a 21 dias de idade, foi conduzido um experimento com 600 pintos de um dia da linhagem Hubbard-MPK. As aves foram distribuídas em um delineamento inteiramente casualizado, arranjo fatorial cinco x dois (níveis de cálcio x sexos), com três repeti es e 20 aves por parcela. A ra o basal, com 0,54% de fósforo total e 600 unidades de fitase/kg, foi balanceada para atender às exigências nutricionais das aves conforme o NRC (1994), exceto para o cálcio, cujos níveis foram 0,46; 0,67; 0,88; 1,09 e 1,30%. Aos 14 dias, duas aves de cada tratamento foram transferidas para gaiolas de metabolismo para coleta total das excretas e aos 21 dias, duas aves de cada tratamento foram abatidas para retirada da tíbia esquerda para análises posteriores. Os machos apresentaram maior consumo e ganho de peso, sendo que este apresentou redu o linear conforme o nível de cálcio foi elevado. Os níveis de 0,67 e 0,71% resultaram em melhor digestibilidade da matéria seca e maior reten o de nitrogênio, respectivamente. As fêmeas apresentaram teores de cinzas e cálcio, na tíbia, superiores aos dos machos (1,68 e 2,34%, respectivamente). O nível de 0,55% de cálcio proporcionou a máxima deposi o de cinzas (51,5%), enquanto o nível de 0,59%, a máxima calcifica o (17,8%). A deposi o de fósforo apresentou efeito quadrático, em fun o dos níveis de cálcio, sendo que o nível de 0,75% proporcionou a maior deposi o (10,8%), e a deposi o de manganês foi reduzida linearmente com a eleva o do nível de cálcio na ra o. Conclui-se que níveis elevados de cálcio em ra es suplementadas com fitase afetaram negativamente o ganho de peso, a deposi o de fósforo e manganês na tíbia e que os baixos níveis prejudicaram a digestibilidade da matéria seca e a reten o de nitrogênio.
Características oclusais de pacientes com Classe II, divis?o 1, tratados sem e com extra??es de dois pré-molares superiores
Graciano, Jo?o Tadeu Amin;Janson, Guilherme;Freitas, Marcos Roberto de;Henriques, José Fernando Castanha;
Dental Press Journal of Orthodontics , 2010, DOI: 10.1590/S2176-94512010000600011
Abstract: objective: the purpose of this study was to identify initial occlusal characteristics of class ii, division 1 patients treated with and without extraction of two upper premolars. methods: for this purpose, 62 patients presenting with class ii, division 1 malocclusion were selected and divided into two groups according to treatment type. group 1 consisted of 42 patients (23 females and 19 males) with a mean age of 12.7 years, who were treated without extractions, with fixed appliance and headgear. group 2 was composed of 20 patients (6 females and 14 males) with a mean age of 13.5 years, also treated with fixed appliance combined with the use of headgear, but group 2 treatment plan indicated the extraction of two premolars. in order to observe initial and final occlusal characteristics as well as changes throughout treatment the treatment priority index (tpi) was used. tpi values were subjected to statistical analysis by the independent t-test to compare variables between groups. results and conclusions: the results showed that the degree of initial malocclusion was different in the two groups when assessed by the tpi, which was higher in the group treated with extraction of two upper premolars
Ultrastructural effects of two phthalocyanines in CHO-K1 and HeLa cells after laser irradiation
de CastroPazos,Marcelo; Pacheco-Soares,Cristina; Soares da Silva,Newton; DaMatta,Renato Augusto; Pacheco,Marcos Tadeu T.;
Biocell , 2003,
Abstract: the effects of photodynamic therapy using 2nd generation photosensitizers have been widely investigated aiming clinical application treatment of solid neoplasms. in this work, ultrastructure changes caused by the action of two 2nd generation photosensitizers and laser irradiation on cho-k1 and hela (neoplastic) cells were analyzed by transmission electron microscopy. aluminum phthalocyanine chloride, aluminum phthalocyanine tetrasulfonate chloride and radiation from a semiconductor laser at a fluency of 0.5 j/cm2 (power=26mw; l=670nm) were used. the results showed induction of apoptosis. such alterations where observed in hela but not in cho-k1 cells after aluminum phthalocyanine tetrasulfonate chloride (alpcs4) photodynamic treatment. the aluminum phthalocyanine chloride (alpc) photodynamic treatment induced necrosis on the neoplastic cell line, and cytoplasm and nuclear alterations on the normal cell line.
Avalia??o de uma sonda genética (Sistema Accuprobe, Gen Probe?) para identifica??o de organismos do complexo Mycobacterium tuberculosis, em compara??o com métodos tradicionais de caracteriza??o
Spada, Delurce Tadeu de Araujo;Santos, Manoel Armando Azevedo dos;Almeida, Elisabete A.;Augusto, Marcos;Albarral, Maria Idemar Pedrosa;Melo, Fernando Augusto Fiuza de;
Jornal Brasileiro de Pneumologia , 2005, DOI: 10.1590/S1806-37132005000300007
Abstract: background: the appearance of tuberculosis/human immunodeficiency virus co-infection and the growing number of diseases caused by nontuberculous mycobacteria, as well as the confusion that these can cause in relation to emerging multidrug-resistant strains, require more accurate and rapid laboratory results, not only in the isolation of strains but also in their identification. objective: a comparative study evaluating a new tool of molecular identification, which uses a genetic probe based on the 16s rdna sequence of the mycobacterium tuberculosis gene (gen-probe accuprobe? gen probe, inc.), and the classic methodology. method: fifty-five mycobacterium strains, isolated from the sputum of patients treated at a tuberculosis reference clinic, were selected for study. subcultures were performed in three tubes: one submitted to genetic identification, one analyzed through classical tests (production and accumulation of niacin; growth in the lowenstein-jensen medium with the inhibitor agents p-nitrobenzoic acid and thiophene-2-carboxylic acid hydrazide added), and one held in reserve. results: the probe identified 51 cases as belonging to the m. tuberculosis complex (one associated with m. kansasii) and the other 4 as nontuberculous mycobacteria, later identified as m. kansasii (3) and m. avium (1). using traditional methods, 47 samples were identified as belonging to the m. tuberculosis complex, 4 were classified as fitting the profile of nontuberculous mycobacteria (in agreement with the genetic probe results), and 4 were unidentified, 1 of which presented the exact characteristics that 2 mycobacterium species have in common. conclusion: the benefits of the molecular biology technique justify its implementation and routine use, in combination with classical methods, in a high-traffic clinic where complex cases of tuberculosis are treated.
Quali-Quantitative Analysis of Brazilian Environmental Licensing of Hydropower Plants  [PDF]
Fabio Giusti Azevedo de Britto, José Paulo Soares de Azevedo, Cynara Alets Sthuasth Souza de Melo Fran?a, Rodrigo Cunha Wanick, Leandro Andrei Beser de Deus, Marcos Aurélio Vasconcelos de Freitas
International Journal of Geosciences (IJG) , 2015, DOI: 10.4236/ijg.2015.67056
Abstract: The use of the extraordinary hydroelectric potential of the Amazon Basin originated an increase in the offer of renewable energy in Brazil, which, in its turn, leads to conflicts and a lack of consensus among different players owing to the potential negative impacts related to the construction and operation of large hydroelectric power plants in relatively well preserved areas. In this context, environmental licensing is one of the national environmental policy’s main instruments for making decisions regarding the use of the hydroelectric potential, especially the rivers of the Amazon Basin. Nevertheless, this significant instrument has its limitations and requires adjustments in order to better aid the decision making process regarding the use of water resources and land with the goal of increasing the offer of electric energy.
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