Arcabouço geofísico, isostasia e causas do magmatismo cenozóico da província Borborema e de sua margem continental (Nordeste do Brasil)

The Borborema Province (BP) is a geologic domain located in Northeastern Brazil. The BP is limited at the south by the São Francisco craton, at the west by the Parnaíba basin, and both at the north and east by coastal sedimentary basins. Nonetheless the BP surface geology is well known, several key aspects of its evolution are still open, notably: i)its tectonic compartmentalization established after the Brasiliano orogenesis, ii) the architecture of its cretaceous continental margin, iii) the elastic properties of its lithosphere, and iv) the causes of magmatism and uplifting which occurred in the Cenozoic. In this thesis, a regional coverage of geophysical data (elevation, gravity, magnetic, geoid height, and surface wave global tomography) were integrated with surface geologic information aiming to attain a better understanding of the above questions. In the Riacho do Pontal belt and in the western sector of the Sergipano belt, the neoproterozoic suture of the collision of the Sul domain of the BP with the Sanfranciscana plate (SFP) is correlated with an expressive dipolar gravity anomaly. The positive lobule of this anomaly is due to the BP lower continental crust uplifting whilst the negative lobule is due to the supracrustal nappes overthrusting the SFP. In the eastern sector of the Sergipano belt, this dipolar gravity anomaly does not exist. However the suture still can be identified at the southern sector of the Marancó complex arc, alongside of the Porto da Folha shear zone, where the SFP N-S geophysical alignments are truncated. The boundary associated to the collision of the Ceará domain of the BP with the West African craton is also correlated with a dipolar gravity anomaly. The positive lobule of this anomaly coincides with the Sobral-Pedro II shear zone whilst the negative lobule is associated with the Santa Quitéria magmatic arc. Judging by their geophysical signatures, the major BP internal boundaries are: i)the western sector of the Pernambuco shear zone and the eastern continuation of this shear zone as the Congo shear zone, ii) the Patos shear zone, and iii) the Jaguaribe shear zone and its southwestern continuation as the Tatajuba shear zone. These boundaries divide the BP in five tectonic domains in the geophysical criteria: Sul, Transversal, Rio Grande do Norte, Ceará, and Médio Coreaú. The Sul domain is characterized by geophysical signatures associated with the BP and SFP collision. The fact that Congo shear zone is now proposed as part of the Transversal domain boundary implies an important change in the original definition of this domain. The Rio Grande do Norte domain presents a highly magnetized crust resulted from the superposition of precambrian and phanerozoic events. The Ceará domain is divided by the Senador Pompeu shear zone in two subdomains: the eastern one corresponds to the Orós-Jaguaribe belt and the western one to the Ceará-Central subdomain. The latter subdomain exhibits a positive ENE-W SW gravity anomaly which was associated to a crustal discontinuity. This discontinuity would have acted as a rampart against to the N-S Brasiliano orogenic nappes. The Médio Coreaú domain also presents a dipolar gravity anomaly. Its positive lobule is due to granulitic rocks whereas the negative one is caused by supracrustal rocks. The boundary between Médio Coreaú and Ceará domains can be traced below the Parnaíba basin sediments by its geophysical signature. The joint analysis of free air anomalies, free air admittances, and effective elastic thickness estimates (Te) revealed that the Brazilian East and Equatorial continental margins have quite different elastic properties. In the first one 10 km < Te < 20 km whereas in the second one Te ≤ 10 km. The weakness of the Equatorial margin lithosphere was caused by the cenozoic magmatism. The BP continental margin presents segmentations; some of them have inheritance from precambrian structures and domains. The segmentations conform markedly with some sedimentary basin features which are below described from south to north. The limit between Sergipe and Alagoas subbasins coincides with the suture between BP and SFP. Te estimates indicates concordantly that in Sergipe subbasin Te is around 20 km while Alagoas subbasin has Te around 10 km, thus revealing that the lithosphere in the Sergipe subbasin has a greater rigidity than the lithosphere in the Alagoas subbasin. Additionally inside the crust beneath Sergipe subbasin occurs a very dense body (underplating or crustal heritage?) which is not present in the crust beneath Alagoas subbasin. The continental margin of the Pernambuco basin (15 < Te < 25 km) presents a very distinct free air edge effect displaying two anomalies. This fact indicates the existence in the Pernambuco plateau of a relatively thick crust. In the Paraíba basin the free air edge effect is quite uniform, Te ≈ 15 km, and the lower crust is abnormally dense probably due to its alteration by a magmatic underplating in the Cenozoic. The Potiguar basin segmentation in three parts was corroborated by the Te estimates: in the Potiguar rift Te ≅ 5 km, in the Aracati platform Te ≅ 25 km, and in the Touros platform Te ≅ 10 km. The observed weakness of the lithosphere in the Potiguar rift segment is due to the high heat flux while the relatively high strength of the lithosphere in the Touros platform may be due to the existence of an archaean crust. The Ceará basin, in the region of Mundaú and Icaraí subbasins, presents a quite uniform free air edge effect and Te ranges from 10 to 15 km. The analysis of the Bouguer admittance revealed that isostasy in BP can be explained with an isostatic model where combined surface and buried loadings are present. The estimated ratio of the buried loading relative to the surface loading is equal to 15. In addition, the lower crust in BP is abnormally dense. These affirmations are particularly adequate to the northern portion of BP where adherence of the observed data to the isostatic model is quite good. Using the same above described isostatic model to calculate the coherence function, it was obtained that a single Te estimate for the entire BP must be lower than 60 km; in addition, the BP north portion has Te around 20 km. Using the conventional elastic flexural model to isostasy, an inversion of crust thickness was performed. It was identified two regions in BP where the crust is thickened: one below the Borborema plateau (associated to an uplifting in the Cenozoic) and the other one in the Ceará domain beneath the Santa Quitéria magmatic arc (a residue associated to the Brasiliano orogenesis). On the other hand, along the Cariri-Potiguar trend, the crust is thinned due to an aborted rifting in the Cretaceous. Based on the interpretation of free air anomalies, it was inferred the existence of a large magmatism in the oceanic crust surrounding the BP, in contrast with the incipient magmatism in the continent as shown by surface geology. In BP a quite important positive geoid anomaly exists. This anomaly is spatially correlated with the Borborema plateau and the Macaú-Queimadas volcanic lineament. The integrated interpretation of geoid height anomaly data, global shear velocity model, and geologic data allow to propose that and Edge Driven Convection (EDC) may have caused the Cenozoic magmatism. The EDC is an instability that presumably occurs at the boundary between thick stable lithosphere and oceanic thin lithosphere. In the BP lithosphere, the EDC mechanism would have dragged the cold lithospheric mantle into the hot asthenospheric mantle thus causing a positive density contrast that would have generated the main component of the geoid height anomaly. In addition, the compatibility of the gravity data with the isostatic model, where combined surface and buried loadings are present, together with the temporal correlation between the Cenozoic magmatism and the Borborema plateau uplifting allow to propose that this uplifting would have been caused by the buoyancy effect of a crustal root generated by a magmatic underplating in the Cenozoic

Caracterização hidrodinâmica e morfo-sedimentar do estuário Potengi e áreas adjascentes: subsídios para controle e recuperação ambiental no caso de derrames de hidrocarboneto

This study presents the Environmental Sensibility Mapping to oil spillings on the Potengi estuary - RN and neighboring coastline through remote sensing data, collecting, treatment and integration of the geomorphologic, oceanographic (temperature, salinity, density, direction and intensity), meteorological (wind speed and direction) and high resolution seismic (bathymetry and sonography) data. The Potengi river estuary is located on the eastern coastline of the Rio Grande do Norte State, being inserted in the geological context for the coastal Pernambuco-Paraíba basin and spreading over 18 km; it shelters the Natal harbor zone and an oil terminal, centralizing, therefore, important oil transport operations that can cause accidental spillings. Under the oceanographic point of view, the Potengi estuary is characterized by the absence of any expressive thermic stratification, being classified as partially mixed, B type according to Pritchard (1955), and 2 type in conformity to the stratification-circulation diagram by Hansen & Rattray (1966). Two main wind systems are responsable for the formation of wave sets that occur in the area. The dynamic tide presents, in the Natal Harbor, mean amplitude in spring and quadrature tides, with around 2.8 and 2m, respectively. The mechanism of saline tide mixing was defined through the salinity which is the main parameter for the identification of this mechanism. Important variations of the salinity mean values (36.32 psu), temperature (28.11ºC) and density (22.96 kg/m3) in the estuarine waters presented features belonging to low latitude regions. The water temperature follows the air temperature variations, in the region, with expressive daily amplitudes. In this study, the identification of the estuarine bed morphology through bathymetric and sonographic analysis, had the purpose to evaluate the influence of the superficial and bottom currents for the bottom shaping. In this way, the use of the side scan sonar showed, to be very useful in the identification of the bottom morphology and its relationship with the predominant action of the tidal currents in the Potengi estuary. Besides, it showed how the sonograms can be a support to the comparison of the several patterns derived from the local hydrodynamic variations. The holocene sediments, which fill the estuarine channel, are predominantly sandy, varying from selected, sometimes silty. The sedimentation is controlled by the environmental hydrodynamic conditions, being recognized two important textural facies: Muddy Facies and Sandy Facies. The distribution of these textural facies apparently oscillates owing to the tidal cycle and flow intensity. Each one of the above mentioned data was integrated in a Geographic Information System (GIS), from which was produced the Environmental Sensibility Map to oil spillings with Coastal Sensibility Index (CSI) to the Potengi estuary. The integrated analysis of these data is essential to oil spilling contingency plans, in order to reduce the spilling environmental consequences and to make efficient the endeavours of contention and cleaning up/removal on the Natal Harbor. This study has the aim to collaborate for the increase of informations about the estuarine environment and contribute to a better management of the question: environment/polluting loads

Caracterização morfológica e sedimentologica da plataforma, continental brasileira adjacente aos municípios de Fortim, Aracati e Icapuí- CE

The study area is located on the Brazilian Continental Shelf adjacent to Ceará State, inserted in the submerged Potiguar Basin. This area was submitted to extensional efforts during Upper Cretaceous, associated to the begining of the rifting that resulted in African and South American Continent separation. The main goal of this research was to better understand the sedimentary and geomorphological characteristics of the continental shelf adjacent to Fortim, Aracati and Icapuí (Ceará State). The used data base included geophysical (sides scan sonar and bathymetry studies) and sedimentological survey, associated to satellite image processing and interpretation. Inferences about suspended material and longshore drift was possible using satellite images, and differente bedforms were characterized such as: different kinds of dunes (longitudinal, cross and oblique), bioclastic banks, paleochannels, flat and rock bottom. The researched area comprehended about 2509,13 km2, where 6 different sedimentary facies, based on sediment composition and texture, could be recognized, such as: Bioclastic Sand, Siliciclastic Sand, Biosiliciclastic Sand, Bioclastic gravel, Biosiliciclastic sand with granule and gravel, and Silicibioclastic sand with granule and gravel. The integration of bathymetric, satellite image, side scan sonar and sedimentological data allow us a better characterization of this continental shelf area, as to advance in the knowledge of the continental shelf of the state of Ceara, a very important area to the oil industry because of its potential exploration and e exploitation, and to environmental survey as well

Caracterização morfodinâmica do estuário do Rio Açu, Macau/RN

Estuaries are coastal environments ephemeral life in geological time, derived from the drowning of the shoreline as a function of elevation relative sea level. Such parallel systems is characterized by having two sources of sediment, the river and the sea. The study area comprises the Acu River estuary, located on the northern coast of Rio Grande do Norte State, in a region of intense economic activity, mainly focused on the exploration of oil onshore and offshore, likely to accidental spills. In the oil sector are developed for salt production, shrimp farming, agriculture, fisheries and tourism, which by interacting with sensitive ecosystems, such as estuaries, may alter the natural conditions, thus making it an area susceptible to contamination is essential in understanding the morphodynamic variables that occur in this environment to obtain an environmental license. Information about the submarine relief the estuaries are of great importance for the planning of the activity of environmental monitoring, development and coastal systems, among others, allowing an easy management of risk areas, and assist in the creation of thematic maps of the main aspects of landscape. Morphodynamic studies were performed in this estuary in different seasonal periods in 2009 to observe and quantify morphological changes that have occurred and relate these to the hydrodynamic forcing from the river and its interaction with the tides. Thus, efforts in this area is possible to know the bottom morphology through records of good quality equipment acquired by high resolution geophysical (side-scan sonar and profiler current by doppler effect). The combination of these data enabled the identification of different forms of bed for the winter and summer that were framed in a lower flow regime and later may have been destroyed or modified forms of generating fund scheme than the number according Froude, with different characteristics due mainly to the variation of the depth and type of sedimentary material they are made, and other hydrodynamic parameters. Thus, these features background regions are printed in the channel, sandy banks and muddy plains that border the entire area

Análise hidrodinâmica e morfodinâmica do complexo estuarino do Rio Piranhas-Açu/RN, Nordeste do Brasil

The aim of this study was the seasonal characterization of the morphology, sedimentology and hydrodynamic of the Açu, Cavalos and Conchas estuaries. These estuaries are inserted in a semi-arid climate area and form the mouth of the hydrographic basin of the Piranhas-Açu river, that represent the discharge of the largest watershed in the state. They are embedded in an environment consisting of a fluvial-marine floodplain, mangrove ecosystem, sandbanks, fields of dunes, spits and sandy beaches. Adjacent to the natural units are the main local socioeconomic activities (oil industry, salt industry, shrimp farming, fishing and tourism) are dependent on this river and its conservation. The environmental monitoring is necessary because it is an area under constant action of coastal processes and at high risk of oil spill. The acquisition and interpretation of hydrodynamic, sonographic and sediment data was conducted in two campaigns, dry season (2010) and rainy season (2011), using respectively the current profiler ADCP Doppler effect, the side-scan sonar and Van Veen sampler. In these estuaries: Açu, Cavalos and Conchas were identified the following types of bedforms: flatbed and Dunes 2-D and 3-D (small to medium size), generated at lower flow regime (Froude number <1). Structures such as ripples were observed in the Açu estuary mouth. The higher values of flow discharge and velocity were recorded in the Açu estuary (434,992 m³.s-¹ and 0,554 m.s-¹). In rainy season, despite the record of highest values of discharge and flow velocities at the mouth, the energy rates upstream did not differ much from the data of the dry season. However, in all estuaries were recorded an increase in speed and flow, with reservation to the flow in the Açu estuary and flow at the mouth of the Conchas estuary. Sediment grain sizes tend to increase towards the mouth of the estuary and these ranged from very fine sand to very coarse sand, medium sand fraction being the most recurrent. Based on the data acquired and analyzed, the estuaries Açu, Cavalos and Conchas are classified as mixed , dominated by waves and tides. According to their morphology, they are classified as estuaries constructed by bar and according to the classification by salinity, estuaries Conchas and Cavalos were ranked as hypersaline estuaries, and Açu as hypersaline and vertically well mixed type C

Caracterização sonográfica e sismoestratigráfica de alta resolução do estuário do Rio Potengi, Natal - RN

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Uso do 5-fluorouracil no intra-operatório da cirurgia do pterígio

Objetivo: Avaliar a efetividade e as complicações com a aplicação do 5- fluorouracil (5-FLU) no intra-operatório da cirurgia do pterígio. Método: Foram avaliados 28 olhos de 26 indivíduos quanto ao tipo e tamanho do pterígio, cirurgias prévias e a resposta ao tratamento cirúrgico (no 7º , 21º , 60º e 90º dia de pós-operatório). Logo após a exerese do pterígio, aplicou-se 5-FLU (25 mg/ml) no leito cirúrgico, durante cinco minutos; a seguir, realizou-se a técnica de deslizamento de retalho conjuntival. Resultados: A maioria dos pacientes tinha mais de 50 anos de idade e apresentava pterígio primário (70,0%), grau II (60,7%), do tipo involutivo (60,7%). No pós-operatório observaram-se: isquemia (10,7%), deiscência da conjuntiva (7,1%), ceratite (3,5%), conjuntivite (3,5%) e recidiva da lesão em 1 olho (3,5%).Conclusão: O 5-FLU se mostrou droga segura e efetiva na prevenção das recidivas, podendo ser usado como coadjuvante no tratamento do pterígio para prevenir recidivas.

Modelos de neovascularização corneana em coelhos: análise morfológica

OBJETIVOS: Comparar em coelhos três modelos experimentais de destruição das células germinativas (CG) do limbo corneano quanto a aspectos morfológicos. MÉTODOS: Foram utilizados 54 coelhos, 108 olhos, subdivididos em 3 grupos experimentais: (G1), (G2) e (G3), formados por 18 coelhos cada, que tiveram o OE submetido às técnicas experimentais (T1), (T2) e (T3), respectivamente, e um grupo controle, formado por 54 olhos contralaterais (OD) dos coelhos do G1, G2 e G3. Quatro parâmetros morfológicos foram estudados: epitélio, resposta inflamatória, vascularização e resposta fibroblástica. RESULTADOS: Com a T1 não houve remoção da totalidade do epitélio límbico, com a T2 houve remoção da quase totalidade do epitélio límbico, com a T3 houve remoção da totalidade do epitélio límbico. A reparação da superfície corneana foi feita por epitélio de fenótipo conjuntival (conjuntivalização) com as três técnicas, havendo aparecimento de células caliciformes a partir do 14º dia, sendo a densidade maior no 28º dia. A resposta inflamatória com a T3 foi mais intensa que com a T1 e T2. A regressão foi mais rápida com a T1 e similar com a T2 e T3. Contribuiu para a turvação corneana principalmente no 14º e 28º dia, concentrando-se, principalmente, na metade estromal anterior, sendo poupada a metade posterior. Foi maior até o 28º dia, decrescendo a partir desse momento. Caracterizou-se, no início, por infiltrado com predomínio de polimorfonucleares e sofreu mudança no 56º dia para infiltrado com predomínio de mononucleares. Os neovasos apareceram a partir do 7º dia, a princípio permearam o estroma do terço médio para cima, progredindo para a superficialização com a regressão do edema estromal. A vascularização com as três técnicas, ao final do experimento, foi superficial no estroma, porém não houve a formação de tecido fibro-escleroso denso ou cicatriz propriamente dita distinta do estroma corneano. CONCLUSÕES: Ocorreu conjuntivalização e neovascularização nas três técnicas experimentais. As T2 e T3 mostraram-se adequadas como possíveis modelos de ampla remoção das CG límbicas, levando a resultados similares nos diversos parâmetros estudados. A T1 se mostrou adequada como modelo de remoção parcial do epitélio límbico.

Surgical treatment of renal cell carcinoma recurrence at the renal fossa following radical nephrectomy

CONTEXTO: A recorrência local única do carcinoma renal de células claras em seu leito renal após nefrectomia radical é um evento raro. Estima-se que essa situação ocorra em 0,8% a 3,6% do total de procedimentos. Comumente, seu diagnóstico é realizado através de tomografia computadorizada de abdômen ou ultra-som renal usados no acompanhamento desses pacientes. É polêmico qual o melhor tratamento dessa rara condição entre urologistas e oncologistas devido aos poucos relatos em literatura. RELATO DE CASO: Relatamos um caso de recidiva neoplásica única no leito renal após quatro anos e meio da nefrectomia radical por adenocarcinoma de células claras, sem evidência de metástases a distância em outros órgãos. O diagnóstico foi realizado por meio de tomografia abdominal em acompanhamento ambulatorial, observando-se massa retroperitoneal em topografia renal. A massa foi retirada por meio de uma incisão subcostal ampliada, em cirurgia sem intercorrências. O paciente evoluiu bem no pós-operatório. Após um ano e meio do procedimento, foi evidenciada uma metástase no pulmão esquerdo, e seis meses após, outra recorrência metastática na nona costela anterior à direita, mesmo com paciente totalmente assintomático. O tratamento cirúrgico agressivo em recorrência local única é um bom método para controlar essa rara doença. Tomografia computadorizada de abdômen deve ser feita em acompanhamento de carcinoma renal por longos períodos após a nefrectomia radical para o diagnóstico de recorrências tardias e o tratamento deve ser feito como o de uma metástase recorrente única.

Fixação de enxerto cutâneo em malha de espessura total com sutura ou cola de fibrina

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

Valor nutricional da silagem de grãos úmidos de milho com diferentes graus de moagem para leitões na fase de creche

Utilizaram-se 72 leitões mestiços (Landrace x Large White), com peso inicial médio de 7,1kg, no experimento de desempenho e 20 leitões mestiços, com peso inicial médio de 18,9kg, no experimento de digestibilidade para avaliar a silagem de grãos úmidos de milho com diferentes granulometrias para leitões em fase de creche. O delineamento experimental foi em blocos ao acaso. em ambos os experimentos avaliaram-se o valor nutricional das silagens com diâmetro geométrico médio (DGM) das partículas de 979, 1168 e 2186µm e do milho seco com DGM das partículas de 594µm. Na fase de zero ao oitavo dia, a silagem proporcionou menor consumo diário de ração (CDR) em relação ao milho seco, e foi verificado aumento linear no CDR com o aumento da granulometria da silagem. A silagem com granulometria média e grossa proporcionou melhora na conversão alimentar (CA) em relação ao milho seco, mas não foi observada diferença no ganho diário de peso (GDP). Para o período total, não foram observadas diferenças estatísticas para CDR e GDP, entretanto a silagem proporcionou melhora na CA em relação ao milho seco havendo efeito linear crescente da granulometria da silagem sobre a CA. A granulometria da silagem não influenciou nos coeficientes de digestibilidade aparente (CDA) da matéria seca e da proteína bruta, porém proporcionou maiores CDA do fósforo e valores de energia digestível em relação ao milho seco. O CDA do cálcio e os valores de energia metabolizável foram maiores para a silagem com granulometria fina e média, comparado ao do milho seco. Houve redução linear do CDA do cálcio com o aumento da granulometria da silagem.

Histochemical and morphological characteristics of the levator ani muscle in rats

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

Alterações anatômicas induzidas por Meloidogyne enterolobii (=M. mayaguensis) e Meloidogyne javanica em tomateiros resistentes a meloidoginose

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

Ultrastructural study of ectomycorrhizas on Pinus caribaea Morelet. var. hondurensis Barr. & Golf. seedlings

A ultraestrutura das ectomicorrizas formadas por Pinus caribaea var. hondurensis inoculado com Pisolithus tinctorius (Pers.) Coker & Couch e Telephora terrestris (Ehrenb.) Fr. foi analisada antes do transplantio dessas mudas para o campo, com o intuito de verificar se o fungo estava estabelecido nas raízes. Os fungos ectomicorrízicos inoculados formaram um manto compacto e bem desenvolvido nas raízes laterais. Nas hifas desse manto foram observados vacúolos, núcleos e septos dolipóricos, enquanto que no citoplasma das hifas da rede de Hartig, que ficam adjacentes às células corticais, foram freqüentemente observados vários núcleos, retículo endoplasmático e mitocôndrias polimórficas. Células corticais altamente vacuolizadas, contendo gotículas de material elétron-denso, apresentaram núcleo e algumas organelas na sua estreita região citoplasmática periférica. As ectomicorrizas de P. caribaea var. hondurensis apresentaram características ultraestruturais de uma associação compatível e fisiologicamente ativa.

Estrutura do pericarpo e da semente de Astronium graveolens Jacq. (Anacardiaceae) com notas taxonômicas

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