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Natural open fractures are present in sidewall cores and in whole-core samples from pre-salt reservoirs in the licence block BM-C-33 in the Campos Basin, Brazil. Open fractures are also observed in borehole image logs, and fracture densities are in general high. The highest density of open fractures is seen in the damage zones above and below larger cavities (amalgamated cavern damage zones (ACDZs)). Outside the ACDZs the fracture density is high in silicified carbonates, where it tends to increase with decreasing porosity. Clean dolomites are less fractured than the silicified interval, while the less brittle argillaceous dolomites have the lowest fracture density. Some fractures appear vuggy on borehole image logs, and fracture densities are high close to vugs and larger cavities. The positive correlation between fractures and vugs is caused by flow of dissolving fluids through open fractures, and fracturing at stress concentrations around vugs. Two major fault zones have been interpreted from borehole image logs that have damage zones with very high fracture density. The well-test permeability is much greater than the matrix permeability estimated from sidewall core and log measurements. This excess permeability is attributed to fractures, in combination with caverns and intervals with frequent vugs. more...

Summary “Block BM-C-33 sits in the SW quadrant of the Campos Basin, approximately 200km off the coast of Rio de Janeiro, Brazil. Three discoveries (Seat, Gavea and Pao de Acucar) were made between 2009 and 2012. Following appraisal, these are now believed to hold reserves of more than one billion barrels of oil equivalent. Reservoirs in Block BM-C-33 were growing in the outer Campos Basin during the Aptian. They sit on top of rotated and eroded fault blocks and paleo volcanic highs. On a regional scale, they can be viewed as a distal continuation of the Coqueiros and Macabu formations. Seismically, the accumulations are characterized by a wedge-shaped and mounded external geometry ( Hunt, et al., 2019 ). The reservoirs of BM-C-33 are unique. The original rock has been subject to a range of diagenetic processes which completely have altered the original mineral assemblage and pore textures. The resulting reservoir rock displays a complex pore network - different from what is observed in other pre-salt reservoirs. Silica is a key component in the reservoirs of BM-C-33. According to recent works ( Lapponi et al, 2019 , Tritlla et al, 2018 ; Tritlla, et al, 2019 ), the origin of the silica is both early, during or shortly after deposition; and late, associated with hydrothermal activity most likely in Mid Albian ( Tritlla et al, 2018 ). Pore types are diverse and pores range in size from micro porosity to meter scale caverns. Measurements of permeability at different scales reflect this diversity. Permeability measurements on SWC’s capture matrix properties and are generally low (a few mD and below). DST’s on the other hand suggest average reservoir scale permeabilities of several hundreds of mD. Frequent and occasionally massive mud losses during drilling of reservoir sections confirm the presence of large-scale pore systems. Reservoir properties in carbonate reservoirs are closely tied to pore types. NMR and BHI (BoreHole Image) logs are keys for typing of matrix and larger scale pores respectively. Lack of whole core and production logs make conceptual models important but alternative scenarios are carried forward to capture the uncertainty span. Characterization of reservoir properties in BM-C-33 depends on multidisciplinary work and integration of data on a wide range of scales. Whilst the matrix holds most of the hydrocarbon in place, excess permeability features as fractures, faults, connected vugs and caverns control flow. This abstract discusses some key features and the work that has been done to characterize them.” more...

There is a high incidence of thrombosis in cancer patients. Retrospective studies indicate that lupus anticoagulant (LA) antibodies can be a thrombosis risk factor in cancer. In 77 patients with different forms of cancer LA and thrombosis incidence were retrospectively evaluated. In a prospective study, with 42 lung adenocarcinoma patients, we measured plasma LA, fibrinogen, factor VIII (FVIII), and thrombosis incidence. A high frequency of LA and thrombosis were observed in both studies. In isolation LA, increased levels of FVIII and fibrinogen could not be considered good markers for the development of thrombosis. more...

Extra-deep reading azimuthal resistivity tools have been deployed in various reservoir settings around the world in recent years in an effort to further improve efficiencies in reservoir development. For many years field development relied on standard and azimuthal propagation resistivity tools with depths of investigation up to approximately 5m, contributing to optimized and pro-active geosteering. While effective at geosteering against adjacent boundaries to maintain position in oil bearing formation, more complex reservoir architectures require data sensing further into the formation to allow a closer correlation with seismic models and provide more complete reservoir mapping. The first extra-deep propagation resistivity tools were developed by employing lower frequency waves, increasing antenna spacing and eventually adding lower frequency azimuthal signals. The new designs greatly increased the depth of detection and also added directional components. However, due to the greater volume of formation being investigated, the deeper readings bring extra complexity and uncertainty to the interpretation process so that innovative inversion software is required to support the tools and produce results that can be used in real-time. The inversion method described in this paper for the interpretation of extra-deep azimuthal resistivities employs a-priori constraints and is user-controlled in order to accurately monitor laterally and vertically changing geology. The examples shown here will demonstrate how inversion results based on a full suite of resistivity measurements have brought benefits to reservoir understanding by deriving sandstone thickness, detecting multiple bed boundaries, locating remote sandstones and remote resistivity plus the relative dip between the tool and the formation. The integration of this data results in better constrained reservoir models and an improved field development strategy. This paper will present the results of wells drilled using extra-deep azimuthal resistivity tools on the Peregrino Field in Brazil. The reservoir comprises complex high energy gravity flows consisting of reservoir units difficult to map due to being below seismic resolution. The sandstones have limited lateral extent and thicknesses ranging from 2m to 25m. Originally developed to improve net sandstone drilled in the Peregrino heavy oil reservoir by allowing a more strategic approach to geosteering, the tool deployment has brought additional benefits in reservoir understanding which impact seismic model interpretation, future well planning, completion strategies and reduce the need of pilot holes. more...

Avaliou-se a produtividade e qualidade do tomate (híbrido Carmen) produzido no sistema denominado FITO, substrato constituído de composto + areia + fertilizantes em saco plástico, em ambiente protegido e campo. Foram estudados sete tratamentos: 1) FITO, conduzido em ambiente protegido, em saco plástico perfurado, com 9 dm³ de substrato por planta, contendo 25% de composto e 75% de areia, sendo todos os macro e micronutrientes colocados via gotejamento; 2) FITO A, similar ao tratamento anterior, entretanto utilizou-se apenas a areia como substrato; 3) FITO 1, similar ao tratamento FITO, sendo que apenas o N e K foram aplicados via gotejamento e os demais nutrientes misturados diretamente no substrato; 4) testemunha em ambiente protegido, com as plantas transplantadas diretamente no solo; 5) FITO C, similar ao tratamento FITO, sendo que neste caso as plantas foram conduzidas em condição de campo; 6) testemunha conduzida em ambiente protegido com mudas transplantadas diretamente no solo, sendo o N e K aplicados via gotejamento; 7) testemunha conduzidas no campo com mudas transplantadas diretamente no solo. O experimento foi delineado em blocos ao acaso e quatro repetições. Não houve efeito significativo dos tratamentos nos teores de N, Zn e Mn nas folhas; na produção de frutos grandes, frutos pequenos e frutos totais; na qualidade do fruto (pH, acidez titulável, sólidos solúveis totais e vitamina C). Houve efeito significativo dos tratamentos sobre o peso da matéria seca das folhas; produção de frutos médios, comerciais, não-comerciais, ponderada e por dia após o transplante (PCD) e nos teores P, K, Ca, Mg, S, Fe e Cu nas folhas. As maiores produtividades comercial, ponderada e PCD, 104,79 t ha-1, 94,71 t ha-1 e 0,851 t ha-1 dia-1, respectivamente, foram obtidas com o sistema FITO; entretanto, elas não diferiram daquelas obtidas na testemunha em ambiente protegido, no solo. O sistema FITO pode substituir o cultivo no solo, tanto em ambiente protegido quanto no campo.The tomato (hybrid Carmen) fruit yield and quality in the FITO system were evaluated, using plastic bags containing organic compost + sand + nutrients, in the field and under unheated greenhouse conditions. Seven treatments were evaluated: 1) FITO, under unheated greenhouse, using perforated plastic bags, with 9 dm³ substratum per plant, containing 25% of organic compost and 75% of sand, all the macro and micronutrientes being added through trickle irrigation; 2) FITO A, similar to the previous treatment, except that only sand was used as substratum; 3) FITO 1, similar to FITO, except that the N and K were applied through trickle irrigation and the other nutrients were directly mixed in the substratum; 4) check plot in unheated greenhouse in which plants were directly transplanted in the soil; 5) FITO C, similar to FITO, except that the plants were cultivated under field condition; 6) check plot in unheated greenhouse in which plants were transplanted to the soil N and K being applied through trickle irrigation; 7) check plot with plants directly transplanted in the soil under field conditions. The experiment was conducted in randomized blocks design with four repetitions. There was no significant effect of treatments on N, Zn and Mn contents in leaf; in big and small sized fruits; in total fruit yield and fruit quality (pH, acidity, total soluble solids and vitamin C). Significant differences were found among treatments for leaf dry weight, medium, commercial and non-commercial production of fruits per day after transplantation (PCD). Significant differences were observed for P, K, Ca, Mg, S, Fe and Cu contents in leaves. The highest commercial, weighted and PCD yields, 104.79 t ha-1, 94,71 t ha-1 and 0.851 t ha-1 day-1, respectively, were obtained with the FITO system. However these values did not differ from those observed in the check plot using soil in the unheated greenhouse. FITO system can substitute the cultivation in the soil, either in the field or in unheated greenhouse. more...

A seismic-based reservoir properties estimation is implemented and tested in this work. The main goal in this work is to map oil saturated sands based on a sandshale oil field system. We consider petrophysical measurements as source of information to construct a conditional probability density function (PDF) for water saturated sand and a conditional PDF for oil saturated sand. Using these PDFs’ and seismic attributes from a reservoir cell, we compute the probability for water saturation given the attributes and the probability for oil saturation given the attributes. From these probabilities and following a Bayesian criterion we create an indicator for saturating fluid to this cell and the associated Bayes error. We analyze each reservoir cell to create a map for oil saturated indicator, water saturated indicator and the associated uncertainty. Several seismic attributes are analyzed in this work and using the maximum entropy measured from these PDFs’ we decide the most informative attributes and attribute pair to reduce uncertainty. In the current time, the methodology was successful tested in well log data. Our next step is to test the methodology with seismic attributes and apply the methodology in a real situation. Introduction The 4D seismic have a wide potential in the monitorating and administration of reservoirs, allowing to identify fluids contacts, no drained oil portions, injection fronts and permeability barriers. The appearance of preferential water paths creates no drained oil areas. The 4D seismic becomes an important tool to identify the reservoir areas that still contains oil and, consequently, to elaborate recovery strategies. Studies for fluid-saturation have been written frequently in the literature. Based on the Biot-Gassman theory, we study the effect of fluid saturation on seismic properties (Han and Batzle, 2004). Relationships between saturation and uncertainty, as predicted from Sengupta and Mavko (1998) and Mukerji et al. (2001), and principally methods based on Bayes criterion to reduce uncertainty (Gonzalez et al., 2002) were also of great interest for our work. A similar work, but more developed, can be founded in Mukerji, Mavko and Takahashi (2002). Only for visualization we study an application using Bayesian estimation theory through a workflow for analysis and prediction (Bachrach et al., 2004). Our goal is to map sand reservoirs filled out by oil, through the seismic attribute answers in different saturation conditions. We use well log data as source of information to build a conditional probability density function (PDF) for an oil filed out sand/shale reservoir situation and to build a PDF for a water filed out sand/shale reservoir situation. Starting from these PDFs’ and the seismic attributes estimated from seismic data associated to a reservoir cell we determine the most probable situation for the associated cell: ifiled oil reservoir cell or iifiled water reservoir cell. A Bayes criterion is applied to this decision. We follow the mathematical theory developed by Takahashi (2000) based in previous works, that involves methods to quantify the information through the probability theory and methods to estimate based in the information, were used thoroughly. Theoretical background To express quantitatively the “state of knowledge” of rocks properties; probability density functions (PDFs’) about these parameters, given a set of well log data representing in situ petrophysical measurement are computed. The “state of knowledge” (Takahashi, 2000), expressed by PDFs’, can describe how well we know the targets and how uncertain our targets are. In estimation problems, the PDFs’, supply a complete and quantitative description of the "state of knowledge " of each observed parameter, becoming a valuable information source. However, as it is waited of the own statistics, the measures don't have a perfect state of knowledge in other words, uncertainty zero. And it doesn't change in geophysical measures. This limitation can have cause in data acquisition, in the present noises, in the complexity of the nature, and in many other difficulties. Therefore, all and any form of minimizing the values uncertainty of properties in subsurface are been worth. In this point of view, it is noticed easily that a unique value they are not sufficient for estimates and that’s the reason because the use of PDFs became viable in this work. Initially, we worked with one-dimension PDFs’, computing PDFs’ for water saturation and oil saturation situations for each one of a series of petrophysical properties. We consider seismic velocities, Impedances, density, and others. To increase the amount of information we starts to work with pair of petrophysical properties, building twodimensional PDFs’ for oil saturation and water saturation situations. This work with a pair of properties was accomplished by the greatest reliability offered when we working with a pair. more...

A quantificação e o fracionamento da matéria orgânica do solo em carbono solúvel, carbono solúvel em solução salina e matéria orgânica leve podem ser usados como ferramentas para caracterizar a recuperação de áreas degradadas. Para este fim, coletaram-se amostras de solos em talude, submetidos à recuperação em novembro de 1994 com vários tipos de cobertura vegetal, no município de Viçosa. Os tratamentos corresponderam a: solo sem vegetação, solo em recuperação com predomínio de leguminosas, solo revegetado com maior presença de gramíneas, solo sob pastagem natural e solo sob floresta. Os resultados mostraram que o fracionamento do carbono orgânico do solo em carbono solúvel em solução salina, matéria orgânica leve e carbono solúvel em água auxilia na caracterização de áreas degradadas. O carbono solúvel em solução salina foi o procedimento mais sensível para caracterizar áreas degradadas a partir de diferentes coberturas vegetais. The characterization and quantification of soil organic matter as water soluble carbon, labile carbon and light organic matter may be used to characterize the rehabilitation of degraded areas. Soil samples were thus collected on a hillside cut submitted to reclamation, presenting different types of vegetal covering during November 1994, in the district of Viçosa. The treatments consisted of areas of soils without vegetation, recovering areas with mainly legumes, recovering areas with mainly grass, soils under grass and soils under natural forest. The results have shown that the fractionation of organic carbon in soluble carbon in saline solution, water soluble carbon, light organic matter help to characterize the degraded areas. The soluble carbon in saline solution seems to be the best method to characterize the degraded areas from different vegetal covers. more...

Os dados do levantamento aerogeofisico muti-metodologico (magnetico, gamaespectrometrico e eletromagnetico-TDEM), conduzido pela CPBM na Area Barreiro, no estado da Bahia, foram interpretados e seus resultados correlacionados para fins de mapeamento geologico. O metodo magnetico proporcionou a identificacao de feicoes lineares associadas com falhas e fraturas, enquanto que, os metodos eletromagnetico e gamaespectrometrico mostraram-se efetivos na identificacao de variacoes litologicas, caracterizadas pelo contraste de condutividade (evidente nos mapas eletromagneticos) e pela variacao na composicao dos radioelementos K, U e Th. A resposta aos metodos geofisicos sugere que estes dados sejam tambem objeto de utilizacao para mapeamento geologico de detalhe, em adicao ao objetivo principal do levantamanto que e a busca de alvos para prospecao. more...

Little has been published about the length and determinants of survival for persons with AIDS in developing countries. This study examined the survival experience of Brazilian AIDS patients from 1982 to 1989.A retrospective cohort study involving record review of reported AIDS cases.We obtained information about 2135 adult AIDS patients in Brazil. Local health officials supplied data regarding demographic and clinical characteristics and length of survival. Statistical techniques of survival analysis were applied.Median survival was 5.1 months, much shorter than in developed countries, and there was no improvement in survival for cases diagnosed more recently. Younger patients and those in the intravenous drug use exposure category lived longer than other AIDS patients. Those presenting with Kaposi's sarcoma, esophageal candidiasis, and tuberculosis fared relatively well, while those presenting with multiple diagnoses or toxoplasmosis did more poorly.These results tend to confirm the predictors of AIDS survival previously reported from developed countries and to document the poor survival of AIDS patients in the developing world. more...

Background: It is largely accepted that cancer patients have a high incidence of thrombosis which is strictly related to prognosis of cancer. Aim: We prospectively evaluated 81 consecutively lung adenocarcinoma patients in order to identify prothrombotic factors and thrombosis incidence. Methods: Patients were submitted to Doppler examination of arms and limbs every three months or in case of thrombosis suspicion. Additional image evaluations were made in case of inconclusive diagnosis. Levels of C protein, platelets, and fibrinogen, factor VIII and IX, D-dimmer, antitrombin and apoptotic microparticles were evaluated each six months. Samples were also tested for lupus anticoagulant (LA) antibodies and levels of IL-1, IL-6 and Tumor Necrosis Factor (TNF). A group of 30 healthy blood donors was used as control. Results: From the studied patients 21% had thrombosis, 38% had fibrinogen above 500 mg/dl, 42% had FVIII activity above 200%, 63% had increased D-dimmer, 60% had more than 1x106 microparticles/ml serum, and none of them have decreased levels of C protein or antitrombin. A small fraction of patients had increase of platelet counts. At immunological evaluation 52% of patients had LA detection and 63% showed increased leves of IL-6. Patients with at least one of the variables thrombosis, high levels of IL-6 (p Conclusion: There is a high incidence of thrombosis in lung adenocarcinoma patients, on which FVIII and LA significantly influenced and microparticles only showed a tendency. However, presence of LA, thrombosis or increased levels of IL-6 or FVIII showed directly interfered with patient’s survival. more...

Na elaboracao deste trabalho, foi desenvolvida uma metodologia para interpretar dados aeromagneticos de forma automatica, visando uma rapida avaliacao da distribuicao de fontes, atraves de uma aplicacao da “equacao Homogenea de Euler”. Para o uso dessa equacao e necessario apenas o campo magnetico e suas tres derivadas, as quais podem ser medidas diretamente ou calculadas a partir do campo magnetico, o que torna possivel a aplicacao do metodo. Com o uso da equacao homogenea de Euler, e possivel formular um problema inverso capaz de estimular o vetor de parâmetros, contendo a localizacao de onde pode existir a fonte e o indice estrutural, o qual depende do tipo de fonte. O problema inverso foi estabilizado com a introducao de informacoes “a priori” no vetor de parâmetros e com uso de uma matriz de pesos. A metodologia foi testada em anomalias teoricas e reais, em regiao de baixa latitude com resultados satisfatorios. A aplicabilidade do metodo e analisada, discutindo-se a ambiguidade causada pela falta de informacoes sobre o vetor magnetizacao do corpo, inerente aos metodos de interpretacao automatica. Como uma aplicacao, foi escolhida uma area na bacia do Solimoes. A partir de 1977, a bacia do Solimoes vem merecendo consideravel atividade exploratoria, motivada pelas primeiras descobertas de gas em arenitos da formacao Monte Alegre. Desde entao, trabalhos de sismica e de perfuracao vem sendo desenvolvidos na regiao. O conhecimento das estruturas do embasamento, e de grande importância para a descoberta de estruturas favoraveis ao trapeamento de hidrocarbonetos e para um melhor conhecimento dos eventos tectonicos. Dessa aplicacao, foi possivel obter informacoes preliminares sobre a distribuicao de intrusoes de corpos magneticos intra-embasamento e supra-embasamento. more...

[This corrects the article DOI: 10.1371/journal.pone.0154893.].

[This corrects the article DOI: 10.1371/journal.pone.0154893.].