936 resultados para Sudden Drawdown


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The development of technology for structural composites has as one of its ends form a set of materials that combine high values of mechanical strength and stiffness and low density. Today, companies like Embraer and PETROBRAS and research institutions like NASA, working with these materials with recognized advantages in terms of weight gain, increased performance and low corrosion. We have developed a systematic study to determine the bond strength between composite carbon fiber / epoxy and fiberglass / epoxy laminate both bonded to a carbon steel which are widely used in the petrochemical industry and repair. For morphological evaluation and bonding between materials of different natures, ultrasound analysis, optical microscopy and stereoscopy were performed. To simulate actual conditions, the composites were subjected to conditioning by using heat shock temperatures from -50 to 80 ° C for 1000 cycles for composite carbon fiber / epoxy composites and 2000 cycles for fiberglass / epoxy . The use of composites studied here proved to be efficient to perform repairs in metallic pipes with application petrochemical, as when exposed to sudden changes of temperature (-50 ° to 80 ° C) cycling at 1000 to 2000 times, its mechanical properties (shear and tensile) practically do not change

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The Inflation Targeting Regime was adopted in Brazil in 1999 and it aims at maintaining the price level in the interval set by the government. For such reason, the Central Bank makes use of variations in the interest rate, which causes the cost of the credit to be more expensive, reducing the investments, the jobs and, concomitantly, the inflation. Being aware that the country is subject to sudden reversals of the international capital flows which results in exchange rate and price instability, an econometric analysis of the adequation of the targerting regime to the Brazilian economy, especially concerned with the index price that is used as the parameter for the inflation calculus, is proposed

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The work consists of analyzing the risk management of investments by applying statistical concepts, economic and mathematical models considering the assets on the market on renowned financial institution. The assessment of these risks becomes increasingly interesting in view of minimizing your losses thus maximizing your chances of gains in both markets boom as extreme uncertainty, even with the sudden changes of scenery. Introducing concepts of investment funds, as well as the classification of the types of funds as funds management and equity, its guidelines, the concept of market investment funds. The types of assets comprising the investment funds, their taxation rules beyond the incidents that market widely used by investors and skilled people, both physical and legal, who keep their resources in this modality. With the historical data collected yields of investment funds of the Bank of Brazil, is an accomplished inflation adjustment and calculated the mean and variance for the verification of the model of Markowitz efficient frontier, a method used as investment analysis. This scan is used Matlab to obtain the set (or border) efficient portfolios. Once verified such data, there will be a critique of the Markowitz model as a quadratic programming and more coherent risk measures currently studied as VaR and CVaR minimizing the expected error, approaching our studies of current research. It is found that such studies have much to be explored, since there are many discussions about how effectively measure risk investments such as its characteristic and behavior, using a time series and volatility

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This paper consists in applying the Modern Theory of Portfolio (MPT) using central position measurements for modeling the return on investment fund of a renowned financial institution and compare with the Medium- CVaR model. The measurement of risks and returns becomes increasingly important for investors to minimize their losses to maximize thus their possibilities of earnings, taking into account sudden change scenarios. We present concepts of investment funds used as data and research on central position measurements to determine which measure was more suitable. To assemble the Efficient Frontier of assets considering the method proposed measure of central position-CVaR position is used MatLab. Then, after getting the Frontier, it was possible to compare it with the Medium-CVaR model, already proven effective. Finally, we analyze the viability of the proposed model in portfolio management

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This paper analyzes data under diametrically opposed theoretical frameworks. Encouraged by the sudden and recent popularity of Hannah Arendt, we decided to submit the data of a already presented dissertation to a “new” reference, extracted from Arendt’s famous text on the education crisis in the United States in the 1950. Data had been interpreted in the light of Paulo Freire’s epistemology. In further analyzes, from Arendt, our interpretations gained even more strength. However, in the final comparison between the two thinkers stand out irreconcilable differences: For Arendt, it is impossible to educate adults and the world of education should be detached from the world of politics, since the responsibility of the educator is based on tradition and authority while for Freire is indeed possible to educate adults and the responsibility of the educator – as in Sartre – leads to freedom. Our conclusion is to be possible the social education of adults if we educate ourselves with them in a dialogic relationship.

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The increasing importance of aesthetic in the Dentistry for the patients and the consumers brought a constant rise in the number of products and procedures to facilitate the confection of the dental bleaching. Concomitantly, thone was a sudden increase in the number of research and publications, in vitro and in vivo, about its possible adverse reactions. Through literature revision this study aims to verify the possible morphologic alterations of the submitted enamel and dentine with different bleaching agents making critical analysis of the results of the current research with relation to the study of the microhardness and superficial roughness.

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The locus coeruleus (LC) is a dorsal pontine region, situated bilaterally on the floor of the fourth ventricle. It is considered to be the major source of noradrenergic innervation in the brain. These neurons are highly sensitive to CO2/pH, and chemical lesions of LC neurons largely attenuate the hypercapnic ventilatory response in unanesthetized adult rats. Developmental dysfunctions in these neurons are linked to pathological conditions such as Rett and sudden infant death syndromes, which can impair the control of the cardio-respiratory system. LC is densely innervated by fibers that contain glutamate, serotonin, and adenosine triphosphate, and these neurotransmitters strongly affect LC activity, including central chemoreflexes. Aside from neurochemical modulation, LC neurons are also strongly electrically coupled, specifically through gap junctions, which play a role in the CO2 ventilatory response. This article reviews the available data on the role of chemical and electrical neuromodulation of the LC in the control of ventilation.

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Introduction: Psychogenic dysphonia is a functional disorder with variable clinical manifestations.Objective: To assess the clinical and vocal characteristics of patients with psychogenic dysphonia in a case series.Methods: The study included 28 adult patients with psychogenic dysphonia, evaluated at a University hospital in the last ten years. Assessed variables included gender, age, occupation, vocal symptoms, vocal characteristics, and videolaryngostroboscopic findings.Results: 28 patients (26 women and 2 men) were assessed. Their occupations included: housekeeper (n = 17), teacher (n = 4), salesclerk (n = 4), nurse (n = 1), retired (n = 1), and psychologist (n = 1). Sudden symptom onset was reported by 16 patients and progressive symptom onset was reported by 12; intermittent evolution was reported by 15; symptom duration longer than three months was reported by 21 patients. Videolaryngostroboscopy showed only functional disorders; no patient had structural lesions or changes in vocal fold mobility. Conversion aphonia, skeletal muscle tension, and intermittent voicing were the most frequent vocal emission manifestation forms.Conclusions: In this case series of patients with psychogenic dysphonia, the most frequent form of clinical presentation was conversion aphonia, followed by musculoskeletal tension and intermittent voicing. The clinical and vocal aspects of 28 patients with psychogenic dysphonia, as well as the particularities of each case, are discussed. (C) 2014 Associacao Brasileira de Otorrinolaringologia e Cirurgia Cervico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

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

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Results of the analysis of dynamic behavior of flashover phenomenon on the high voltage-polluted insulators are presented. These results were taken from a mathematical and an experimental model that introduce the variable thickness influence of the layer pollution deposited on the high-voltage insulator surface. Analysis of the flashover was done by way of introducing a variation in the thickness of the channel of Obenaus' model, simulating a layer pollution of variable thickness. The objective was to obtain a better reproduction of the real layer pollution deposited on the insulator that works in the polluted regions. Two types of thickness variations were used: a sudden variation, using a step; and a soft variation, using a ramp; that were put along the way of the discharge. Comparison between the mathematical and experimental models showed that introduction of a ramp makes Obenaus' model more efficient in analyzing behavior of flashover phenomenon.

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OBJECTIVE: To alert pediatricians about the possibillity of childhood Idiopathic Pulmonary Hemosiderosis, in cases of anemia associated with chronic lung disease. METHODS: This article documents a case of Idiopathic Pulmonary Hemosiderosis in a 6 year-old child, with histopathological documentation, and reviews it against published literature. RESULTS: A 6 year-old child with history of anemia and lung disease characterized by wheezing, recurrent pneumonia and digital clubbing was admitted to the hospital for investigation, where he suffered sudden respiratory failure and hemoptysis.He was submitted to a lung biopsy which showed a histopathological diagnosis compatible with pulmonary hemosiderosis. Therapy with high doses of corticosteroids was initiated with a good early response. After two and a half months of therapy he had a new bleeding episode, culminating in death. CONCLUSIONS: Idiopathic Pulmonary Hemosiderosis should be included as a possible diagnosis of children with anemia and chronic lung disease. This case is a good example.

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Rapid growth in broilers is associated with susceptibility to metabolic disorders such as pulmonary hypertension syndrome (ascites) and sudden death. This study describes a genome search for QTL associated with relative weight of cardio respiratory and metabolically important organs (heart, lungs, liver and gizzard), and hematocrit value in a Brazilian broiler-layer cross. QTL with similar or different effects across sexes were investigated. At 42 days of age after fasted for 6 h, the F2 chickens were weighed and slaughtered. Weights and percentages of the weight relative to BW42 of gizzard, heart, lungs, liver and hematocrit were used in the QTL search. Parental, F1 and F2 individuals were genotyped with 128 genetic markers (127 microsatellites and 1 SNP) covering 22 linkage groups. QTL mapping analyses were carried out using mixed models. A total of 11 genome-wide significant QTL and five suggestive linkages were mapped. Thus, genome-wide significant QTL with similar effects across sexes were mapped to GGA2, 4 and 14 for heart weight, and to GGA2, 8 and 12 for gizzard %. Additionally, five genome-wide significant QTL with different effects across sexes were mapped to GGA 8, 19 and 26 for heart weight; GGA26 for heart % and GGA3 for hematocrit value. Five QTL were detected in chromosomal regions where QTL for similar traits were previously mapped in other F2 chicken populations. Seven novel genome-wide significant QTL are reported here, and 21 positional candidate genes in QTL regions were identified.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)