42 resultados para Fluxo expiratório máximo

em Universidade Federal do Rio Grande do Norte(UFRN)


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In asthmatic, the lung hyperinflation leaves the inspiratory muscle at a suboptimal position in length-tension relationship, reducing the capacity of to generate tension. The increase in transversal section area of the inspiratory muscles could reverse or delay the deterioration of inspiratory muscle function. Objective: To evaluate the evidence for the efficacy of inspiratory muscle training (IMT) with an external resistive device in patients with asthma. Methods: A systematic review with meta-analysis was carried out. The sources researched were the Cochrane Airways Group Specialised Register of trials, Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 11 of 12, 2012), MEDLINE, EMBASE, PsycINFO, CINAHL, AMED, ClinicalTrials.gov and reference lists of articles. All databases were searched from their inception up to November 2012 and there was no restriction on the language of publication. Randomised controlled trials that involved the use of an external inspiratory muscle training device versus a control (sham or no inspiratory training device) were considered for inclusion. Two reviewers independently selected articles for inclusion, evaluated risk of bias in studies and extracted data. Results: A total of five studies involving 113 asthmatic patients were included. Three clinical trials were produced by the same group. The included studies showed a significant increase in maximal inspiratory pressure (MD 13.34 cmH2O, 95% CI 4.70 to 21.98), although the confidence intervals were wide. There was no statistically significant difference between the IMT group and the control group for maximal expiratory pressure, peak expiratory flow rate, forced expiratory volume in one second, forced vital capacity, sensation of dyspnea and use of beta2-agonist. There were no studies describing exacerbation events that required a course of oral and inhaled corticosteroids or emergency department visits, inspiratory muscle endurance, hospital admissions and days of work or school. Conclusions: There is no conclusive evidence in this review to support or refute inspiratory muscle training for asthma, once the evidence was limited by the small number of studies included, number of participants in them together with the risk of bias. More well conducted randomized controlled trials are needed, such trials should investigate respiratory muscle strength, exacerbation rate, lung function, symptoms, hospital admissions, use of medications and days off work or school. IMT should also be assessed in the context of more severe asthma

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This study analyzed measurements of the aeolian transport using vertical sand traps across the field dunes of Jenipabu, in the municipality of Extremoz, Rio Grande do Norte state to the North of Natal city. These measurements were used as parameters for the sand aeolian transport in the region. Before the field trips a map of landscape units was made. Three visits to the field were done in September 2011 (field a - the 13th, field b - the 21st, field c - the 29th), period of the year with the highest wind speed, and another in December 8th, 2011 (field d ) when the wind speed starts to decrease. The sand traps used were of the type "I" with collecting opening of 25 cm from the surface level, and type "S" with collecting opening of 25 cm located 25 cm from the surface level in six collecting points in two of the visits (fields a and d ), and sand traps of the type "T" with the collecting opening of 50 cm from the surface level in the other field trips (fields "b" and "c"). A set of records was also collected by using a portable meteorological station complemented with information such as frequency and intensity of winds, precipitation and relative air humidity in the region, from the Estação Meteorológica de Natal , located 12 km from the study area. The sediments collected were treated and the data obtained permitted calculating the ratio of sediment transport. In September, the sedimentation ratio varied from 0.01 to 11.39 kg.m-1.h-1 and in December this ratio varied from 0.33 to 1.30 kg.m-1.h-1 in the type T collectors. In type I collectors they ranged from 0.01 to 11.39 kg.m-1.h-1, while the same parameters varied from 0.01 to 0.73 kg.m-1.h-1 in type S collector. Based on the statistical analysis done, we concluded that the sediment transport increased proportionally to the wind speed 25 cm from the surface. However, this is not true above 25 cm from the surface. The transport of sediments is more intense near the surface where sedimentation ratios greater than 10 kg.m-1.h-1 were found, whilst a maximum value of 3 kg.m-1.h-1 was observed 25 cm below the surface. The volume of sediments collected increases with the increasing wind speed at the surface level, whereas this relationship is opposed far away from that surface

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The technique of surface coating using magnetron sputtering is one of the most widely used in the surface engineering, for its versatility in obtaining different films as well as in the micro / nanometric thickness control. Among the various process parameters, those related to the active species of the plasma are of the most fundamental importance in the mechanism and kinetics of deposition. In order to identify the active species of the plasma, parameters such as gas flow, pressure and density of electric power were varied during titanium coating on glass substrate. By flowing argon gas of 10, 20, 30, 40 and 50 sccm (cubic centimeters per minute) for each gas flow a sequential scan of the electric current of 0.10, 0.20, 0.30, 0.40 , 0.50 A. The maximum value of 0.50 A was chosen based both on literature data and on limitations of the equipment. The monitoring of plasma species present during the deposition was carried out in situ by the technique of optical emission spectroscopy (OES) through the spectrometer Ocean Optics USB2000 Series. For this purpose, an apparatus was developed to adapt the OES inside the plasma reactor to stay positioned closest to the target. The radiations emitted by the species were detected by an optical fiber placed behind the glass substrate and their intensities as a function of wavelength were, displayed on a monitor screen. The acquisition time for each condition of the plain parameters was related to the minima of spectral lines intensities due to the film formed on the substrate. The intensities of different emission lines of argon and titanium were then analyzed as a function of time, to determine the active species and estimate the thickness of the deposited films. After the deposition, the coated glasses thin films were characterized by optical transmittance through an infrared laser. It was found that the thickness and deposition rate determined by in situ analysis were consistent with the results obtained by laser transmittance

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Until the early 90s, the simulation of fluid flow in oil reservoir basically used the numerical technique of finite differences. Since then, there was a big development in simulation technology based on streamlines, so that nowadays it is being used in several cases and it can represent the physical mechanisms that influence the fluid flow, such as compressibility, capillarity and gravitational segregation. Streamline-based flow simulation is a tool that can help enough in waterflood project management, because it provides important information not available through traditional simulation of finite differences and shows, in a direct way, the influence between injector well and producer well. This work presents the application of a methodology published in literature for optimizing water injection projects in modeling of a Brazilian Potiguar Basin reservoir that has a large number of wells. This methodology considers changes of injection well rates over time, based on information available through streamline simulation. This methodology reduces injection rates in wells of lower efficiency and increases injection rates in more efficient wells. In the proposed model, the methodology was effective. The optimized alternatives presented higher oil recovery associated with a lower water injection volume. This shows better efficiency and, consequently, reduction in costs. Considering the wide use of the water injection in oil fields, the positive outcome of the modeling is important, because it shows a case study of increasing of oil recovery achieved simply through better distribution of water injection rates

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Water injection is the most widely used method for supplementary recovery in many oil fields due to various reasons, like the fact that water is an effective displacing agent of low viscosity oils, the water injection projects are relatively simple to establish and the water availability at a relatively low cost. For design of water injection projects is necessary to do reservoir studies in order to define the various parameters needed to increase the effectiveness of the method. For this kind of study can be used several mathematical models classified into two general categories: analytical or numerical. The present work aims to do a comparative analysis between the results presented by flow lines simulator and conventional finite differences simulator; both types of simulators are based on numerical methods designed to model light oil reservoirs subjected to water injection. Therefore, it was defined two reservoir models: the first one was a heterogeneous model whose petrophysical properties vary along the reservoir and the other one was created using average petrophysical properties obtained from the first model. Comparisons were done considering that the results of these two models were always in the same operational conditions. Then some rock and fluid parameters have been changed in both models and again the results were compared. From the factorial design, that was done to study the sensitivity analysis of reservoir parameters, a few cases were chosen to study the role of water injection rate and the vertical position of wells perforations in production forecast. It was observed that the results from the two simulators are quite similar in most of the cases; differences were found only in those cases where there was an increase in gas solubility ratio of the model. Thus, it was concluded that in flow simulation of reservoirs analogous of those now studied, mainly when the gas solubility ratio is low, the conventional finite differences simulator may be replaced by flow lines simulator the production forecast is compatible but the computational processing time is lower.

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The present study provides a methodology that gives a predictive character the computer simulations based on detailed models of the geometry of a porous medium. We using the software FLUENT to investigate the flow of a viscous Newtonian fluid through a random fractal medium which simplifies a two-dimensional disordered porous medium representing a petroleum reservoir. This fractal model is formed by obstacles of various sizes, whose size distribution function follows a power law where exponent is defined as the fractal dimension of fractionation Dff of the model characterizing the process of fragmentation these obstacles. They are randomly disposed in a rectangular channel. The modeling process incorporates modern concepts, scaling laws, to analyze the influence of heterogeneity found in the fields of the porosity and of the permeability in such a way as to characterize the medium in terms of their fractal properties. This procedure allows numerically analyze the measurements of permeability k and the drag coefficient Cd proposed relationships, like power law, for these properties on various modeling schemes. The purpose of this research is to study the variability provided by these heterogeneities where the velocity field and other details of viscous fluid dynamics are obtained by solving numerically the continuity and Navier-Stokes equations at pore level and observe how the fractal dimension of fractionation of the model can affect their hydrodynamic properties. This study were considered two classes of models, models with constant porosity, MPC, and models with varying porosity, MPV. The results have allowed us to find numerical relationship between the permeability, drag coefficient and the fractal dimension of fractionation of the medium. Based on these numerical results we have proposed scaling relations and algebraic expressions involving the relevant parameters of the phenomenon. In this study analytical equations were determined for Dff depending on the geometrical parameters of the models. We also found a relation between the permeability and the drag coefficient which is inversely proportional to one another. As for the difference in behavior it is most striking in the classes of models MPV. That is, the fact that the porosity vary in these models is an additional factor that plays a significant role in flow analysis. Finally, the results proved satisfactory and consistent, which demonstrates the effectiveness of the referred methodology for all applications analyzed in this study.

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The dams are limnic ecosystems of great importance for its multiple uses, among them, water supply for the public and to culture of artisanal fish are most relevant. The aim of the present study is to evaluate the physical-chemical characteristics and the phytoplankton community in two chosen sites (Point 1 littoral zone of point source; Point 2 pelagic zone of non-point source) of the Minister João Alves dam, which is also known as Boqueirão de Parelhas/RN. This represents the spatial distribution of the phytoplankton species in order to understand any possible alterations of the water quality and the phytoplankton composition in relation to the water quality originating from the impact of the tilapia, Oreochromis niloticus, culture. The study period also encompasses temporal variations exhibited in two seasons of an annual cycle, one during the dry season (Oct, Nov and Dec of 2008 and Jan of 2009), and the other rainy season (Mar, Apr, May and June of 2008) to extend the observation. The physicalchemical parameters, such as pH, temperature, electrical conductivity, concentration of dissolved oxygen were measured in situ and the values of the inorganic nutrients (nitrate, ammonium and orto-phosfato) and chlorophyll in the laboratory. The quali-quantitative analyses of the phytoplankton had been carried through sedimentation technique and the enumeration of the random of 400 cells, colonies and filaments counted using Sedgwick-Rafter counting chamber. The results of pH varied widely from the acidic to alkaline range with the minimum of 5.8 (± 0.8) and the maximum of 9.2 (± 0.7-0.8), at point 1 and 2. The dissolved oxygen content was higher in the rainy period than that in the dry period. The maximum electrical conductivity was of 1409 μScm-1 in point 1 and 431 minim of μScm-1, in point 2. There was a considerable alteration in the levels of inorganic nutrients such as nitrate-nitrogen, ammoniacal nitrogen and orthophosphate during the two cycles of study period. Phytoplankton assemblages presented a picture of alternate dominance among species Cyanobacteria, Bacillariophyceae and Chlorophyceae. The trophic state index diagnosed to the category of mesotrophic, which is based on the values of chlorophyll, total phosphorus and Secchi-disc measurements. The wind driven turbulence of the water column and the fresh inflow of water (flushing and dilution) during rainy season acted as constraint and did-not allow an exaggerated growth of the species of cyanobacteria. On the basis of the present we conclude that the culture of tilapias in cage-culture fails to produce pollution load that could compromise the quality of the water of the dam, probably be due to small dimension of the culture in relation to the size, volume of the water and the reservoir capacity support its own environment

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The relation between metabolic demand and maximal oxygen consumption during exercise have been investigated in different areas of knowledge. In the health field, the determination of maximal oxygen consumption (VO2max) is considered a method to classify the level of physical fitness or the risk of cardiocirculatory diseases. The accuracy to obtain data provides a better evaluation of functional responses and allows a reduction in the error margin at the moment of risk classification, as well as, at the moment of determination of aerobic exercise work load. In Brasil, the use of respirometry associated to ergometric test became an opition in the cardiorespiratory evaluation. This equipment allows predictions concerning the oxyredutase process, making it possible to identify physiological responses to physical effort as the respiratory threshold. This thesis focused in the development of mathematical models developed by multiple regression validated by the stepwise method, aiming to predict the VO2max based on respiratory responses to physical effort. The sample was composed of a ramdom sample of 181 healthy individuals, men and women, that were randomized to two groups: regression group and cross validation group (GV). The voluntiars were submitted to a incremental treadmill test; objetiving to determinate of the second respiratory threshold (LVII) and the Peak VO2max. Using the método forward addition method 11 models of VO2max prediction in trendmill were developded. No significative differences were found between the VO2max meansured and the predicted by models when they were compared using ANOVA One-Way and the Post Hoc test of Turkey. We concluded that the developed mathematical models allow a prediction of the VO2max of healthy young individuals based on the LVII

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Chronic lymphocytic leukemia (B-CLL) is a clonal proliferation of mature B lymphocytes characterized by indolent clinical course. Biologically this clonallity is characterized by low expression of surface immunoglobulin (sIg) with restriction to a single immunoglobulin light chain associated with high expression of CD5 antigen and positivity to B cell antigens lymphocytes such as CD19, CD20 and CD23 and negativity to FMC7. The immunological profile and morphological analysis of lymphoid cells are the main means for the differential diagnosis of B-CLL from other chronic lymphoproliferative diseases. The aim of this study was to evaluate the expression pattern of a variety of membrane antigens in leukemic cells originating from patients with B-CLL. In this study, peripheral blood samples from 80 patients with B-CLL were analyzed by multiparametric flow cytometry in addition to routine hematologic exams, using a panel of monoclonal antibodies (MoAb): CD45/CD14, CD3/CD19/CD45, CD4/CD8 / CD3, CD20/CD5/CD3, CD3/CD16-56/CD45, CD2/CD7, FMC7/CD23, CD103/CD22/CD20, HLADR/CD38, CD10/CD19, CD1a, CD11b and also IgM/gD, kappa and lambda immunoglobulin light chains for the detection of surface immunoglobulin and clonal restriction for immunoglobulin light chain. The Hematological data were obtained from the hematological analyzer and cytomorphological analysis in blood film stained by Leishmann. The study samples consisted of 45 men and 35 women, ages ranging from 55 to 84 years (mean 65 years). Complete white blood count showed count ranging from 10.0 to 42.0 x 109/l. (mean 50.0 x 109/l) and lymphocytes count greater than 5.0 x 109/l in all cases. The neoplastic cells displayed B-CLL phenotype (CD5+/CD19+/CD20+/HLADR+/CD23+) in the vast majority of the cases, associated to failed to stain for T cell markers (CD1a, CD2, CD4, CD3, CD7, CD8), CD103, CD14 and FMC7. Leukemic cells of most patients also expressed low intensity of IgM and IgD with restricted kappa light chain, in most cases (59,7%). This observation highlights the importance of immunophenotyping for correct diagnosis of chronic lymphoproliferative syndromes and the panel of MoAb used was sufficient for diagnostic confirmation of B-CLL

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The acute myeloid leukemia (AML) is a disease in which malignant myeloblasts expand, build up and suppress normal hematopoietic activity would represent a major diagnostic challenge. With the advent of immunophenotyping by flow cytometry, the diagnosis of these tumors have become more faithful, facilitating the treatment and monitoring of patients. The objectives of this study: diagnosis and classification of AML based on immunophenotyping by flow cytometry with a panel of AcMo specific for acute leukemias, set the frequency of AML in samples from patients with acute leukemias sent to the Department of Hematology Blood Center of Rio Grande do Norte - HEMONORTE, establish standards of antigen expression for different subtypes of acute leukemia and its correlation with the newly diagnosed cases refractory to treatment and recurrence of the disease, standardization of methods for detection and labeling of surface antigens by flow cytometry and intracytoplasmic flow, and observe the frequency of acute leukemia with aberrant phenotypes rare. During the study, 351 were diagnosed acute leukemia, and 179 (51%) classified as AML and 172 (49%) and ALL, which were excluded from the present work. Of the 179 AML, 92 (51.4%) were female and 87 (48.6%) were male, with ages ranging from 3 to 95 years of ag, with higher incidence in individuals in the age group of 41 to 65. Splenomegaly was the clinical finding more present, a total of 147 cases (82.1%), followed by hepatomegaly present in 132 cases (73.7%). The hemorrhagic events were observed in 55 cases (30.7%). Lymphadenopathy in turn was detected in 20 of 179 cases (11.2%). In order to classify subtypes of AML, we used a large panel of monoclonal antibodies, obtaining the following results: AML M0, 02 (1.1%) AML M1, 40 (22.3) AML M2, 60 (33.5) AML M3, 22 (12.3%) AML M4, 10 (5.6) AML M5, 13 (7.3%) AML M6 06 (3.4%) and AML M7 01 (0.6%). We observed some cases with aberrant expression of some antigens such as CD7, CD4, CD19, CD3, CD5 and TdT, CD 7 was present in 30 (16.8%), CD4 in 5 (2.8%), the CD 3 in 5 (2.8%), the CD19 in 3 (1.7%), the CD5 in 3 (1.7%) and TDT was in 7 (3.9%) cases of AML .the CD8 and CD79a was present in only a 1 case.

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It is an ethnographic work that has an objective of verifying devices throngh the residents of a low income suburban area, and the way they deal with their social relations through sonsumerism (and the aspiration connected to it), the symbolic character acquired through consumer goods, understood as one of the fundamental components for the comprehension of the web as relations that established, Though consumerism, individuais will reveal ways of communication, of the status, of creating new forms of action and identification. Using the principal that believes in a web of symbolic significance where own individuais develop their impressions, as a resource to look at their own bodies, a social order (yet unstable), and the process of inclusion in a broader society. In conclusion, the act of consuming is more than a perspective that establishes statistics on consumer goods, with their ways of production, circulation and economic functioning: it is also a way of perceiving a collection mapped by consumers individually and socially, and by those means organizing, classifying and identifyring the social world

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This work describes the study and the implementation of the vector speed control for a three-phase Bearingless induction machine with divided winding of 4 poles and 1,1 kW using the neural rotor flux estimation. The vector speed control operates together with the radial positioning controllers and with the winding currents controllers of the stator phases. For the radial positioning, the forces controlled by the internal machine magnetic fields are used. For the radial forces optimization , a special rotor winding with independent circuits which allows a low rotational torque influence was used. The neural flux estimation applied to the vector speed controls has the objective of compensating the parameter dependences of the conventional estimators in relation to the parameter machine s variations due to the temperature increases or due to the rotor magnetic saturation. The implemented control system allows a direct comparison between the respective responses of the speed and radial positioning controllers to the machine oriented by the neural rotor flux estimator in relation to the conventional flux estimator. All the system control is executed by a program developed in the ANSI C language. The DSP resources used by the system are: the Analog/Digital channels converters, the PWM outputs and the parallel and RS-232 serial interfaces, which are responsible, respectively, by the DSP programming and the data capture through the supervisory system

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This work describes the study and the implementation of the speed control for a three-phase induction motor of 1,1 kW and 4 poles using the neural rotor flux estimation. The vector speed control operates together with the winding currents controller of the stator phasis. The neural flux estimation applied to the vector speed controls has the objective of compensating the parameter dependences of the conventional estimators in relation to the parameter machine s variations due to the temperature increases or due to the rotor magnetic saturation. The implemented control system allows a direct comparison between the respective responses of the speed controls to the machine oriented by the neural rotor flux estimator in relation to the conventional flux estimator. All the system control is executed by a program developed in the ANSI C language. The main DSP recources used by the system are, respectively, the Analog/Digital channels converters, the PWM outputs and the parallel and RS-232 serial interfaces, which are responsible, respectively, by the DSP programming and the data capture through the supervisory system

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The present work presents an algorithm proposal, which aims for controlling and improving idle time to be applied in oil production wells equipped with beam pump. The algorithm was totally designed based on existing papers and data acquired from two Potiguar Basin pilot wells. Oil engineering concepts such as submergence, pump off, Basic Sediments and Water (BSW), Inflow Performance Relationship (IPR), reservo ir pressure, inflow pressure, among others, were included into the algorithm through a mathematical treatment developed from a typical well and then extended to the general cases. The optimization will increase the well production potential maximum utilization having the smallest number of pumping unit cycles directly reflecting on operational cost and electricity consumption reduction

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The objective of the present work is develop a model to simulate electrical energy networks in transient and stead states, using the software ATP (Alternative Transient Program), able to be a way to join two distinct themes, present in classical methodology planning networks: short circuit analysis and load flow theory. Beyond that, using a tool for relay simulation, this paper intend to use the new developed model to investigate the influence of transient phenomenon in operation of protection relays, and calibrate the enterprise's protections relays. For testing the model, some relays, actually, installed at COSERN were used