A distribuição F generalizada para selecionar modelos de sobrevivência com fração de cura

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Estudo Comparativo de gráaficos de probabilidade normal para Anáalise de experimentos fatoriais não replicados

Two-level factorial designs are widely used in industrial experimentation. However, many factors in such a design require a large number of runs to perform the experiment, and too many replications of the treatments may not be feasible, considering limitations of resources and of time, making it expensive. In these cases, unreplicated designs are used. But, with only one replicate, there is no internal estimate of experimental error to make judgments about the significance of the observed efects. One of the possible solutions for this problem is to use normal plots or half-normal plots of the efects. Many experimenters use the normal plot, while others prefer the half-normal plot and, often, for both cases, without justification. The controversy about the use of these two graphical techniques motivates this work, once there is no register of formal procedure or statistical test that indicates \which one is best". The choice between the two plots seems to be a subjective issue. The central objective of this master's thesis is, then, to perform an experimental comparative study of the normal plot and half-normal plot in the context of the analysis of the 2k unreplicated factorial experiments. This study involves the construction of simulated scenarios, in which the graphics performance to detect significant efects and to identify outliers is evaluated in order to verify the following questions: Can be a plot better than other? In which situations? What kind of information does a plot increase to the analysis of the experiment that might complement those provided by the other plot? What are the restrictions on the use of graphics? Herewith, this work intends to confront these two techniques; to examine them simultaneously in order to identify similarities, diferences or relationships that contribute to the construction of a theoretical reference to justify or to aid in the experimenter's decision about which of the two graphical techniques to use and the reason for this use. The simulation results show that the half-normal plot is better to assist in the judgement of the efects, while the normal plot is recommended to detect outliers in the data

Função de distribuição generalizada aplicada à velocidade de rotação estelar

In the present work we use a Tsallis maximum entropy distribution law to fit the observations of projected rotational velocity measurements of stars in the Pleiades open cluster. This new distribution funtion which generalizes the Ma.xwel1-Boltzmann one is derived from the non-extensivity of the Boltzmann-Gibbs entropy. We also present a oomparison between results from the generalized distribution and the Ma.xwellia.n law, and show that the generalized distribution fits more closely the observational data. In addition, we present a oomparison between the q values of the generalized distribution determined for the V sin i distribution of the main sequence stars (Pleiades) and ones found for the observed distribution of evolved stars (subgiants). We then observe a correlation between the q values and the star evolution stage for a certain range of stel1ar mass

Caracterização estatística de processos sísmicos via Distribuição Generalizada de Pareto. Estudo de caso: João Câmara-RN

The work is to make a brief discussion of methods to estimate the parameters of the Generalized Pareto distribution (GPD). Being addressed the following techniques: Moments (moments), Maximum Likelihood (MLE), Biased Probability Weighted Moments (PWMB), Unbiased Probability Weighted Moments (PWMU), Mean Power Density Divergence (MDPD), Median (MED), Pickands (PICKANDS), Maximum Penalized Likelihood (MPLE), Maximum Goodness-of-fit (MGF) and the Maximum Entropy (POME) technique, the focus of this manuscript. By way of illustration adjustments were made for the Generalized Pareto distribution, for a sequence of earthquakes intraplacas which occurred in the city of João Câmara in the northeastern region of Brazil, which was monitored continuously for two years (1987 and 1988). It was found that the MLE and POME were the most efficient methods, giving them basically mean squared errors. Based on the threshold of 1.5 degrees was estimated the seismic risk for the city, and estimated the level of return to earthquakes of intensity 1.5°, 2.0°, 2.5°, 3.0° and the most intense earthquake never registered in the city, which occurred in November 1986 with magnitude of about 5.2º

Análise da distribuição do volume pulmonar total e compartimental de crianças com peso normal e obesidade em diferentes posturas

Introdução: A obesidade infantil apresenta incidência crescente e as possíveis comorbidades, como alteração da função respiratória, estão cada vez mais presente nessa faixa etária. O tecido adiposo impõe carga ao sistema respiratório o que leva a um padrão restritivo. Essa condição sofre alterações com as mudanças posturais, onde a gravidade influencia o padrão respiratório de acordo com o posicionamento adotado. Objetivo: Avaliar a distribuição dos volumes total e regional e o movimento tóracoabdominal de crianças e adolescentes que estão acima do peso nas posturas supino e sentado. Métodos: Cinqüenta e duas crianças/adolescentes (8-12 anos) divididas em três grupos: Grupo Obeso (GO=22); Grupo Sobrepeso (GSP=9); Grupo Controle (GC=21) foram avaliadas quanto às medidas antropométricas, teste de função pulmonar, exame das pressões respiratórias máxima e a pletismografia optoeletrônica em duas posturas, supino e sentado, durante a respiração tranquila. Resultados: As crianças que estão obesas apresentaram maiores valores em relação ao GSP e GC das seguintes variáveis espirométricas: volume expiratório forçado no primeiro segundo (VEF1) (p<0.05) e capacidade vital forçada (CVF) (p<0.01). No exame de manovacuometria o GO apresentou um aumento na pressão inspiratória máxima (PImáx) (p<0.01) em comparação com os outros grupos. Quanto à distribuição do volume corrente, o GO possui uma maior contribuição do compartimento abdominal (AB) na postura supina (p<0.05) em relação ao GC e GSP, enquanto que na postura sentada os grupos não diferiram em relação à distribuição dos volumes. O GO apresentou maior assincronia na postura supina (p<0.05) e maior velocidade de encurtamento (p<0.05) em relação os outros grupos. Conclusão: A obesidade em crianças/adolescentes não provoca prejuízos na função pulmonar, incrementa a força muscular inspiratória, aumenta a participação do compartimento AB e a assincronia no MTA na postura em supino, conclui-se que a postura supina associada à obesidade provoca aumento da sobrecarga do diafragma, desfavorecendo o desempenho do sistema respiratório.

Análise estatística de impedância da pele

In this work we analyze the skin bioimpedance statistical distribution. We focus on the study of two distinct samples: the statistics of impedance of several points in the skin of a single individual and the statistics over a population (many individuals) but in a single skin point. The impedance data was obtained from the literature (Pearson, 2007). Using the Shapiro-Wilk test and the assymmetry test we conclude that the impedance of a population is better described by an assymetric and non-normal distribution. On the other side, the data concerning the individual impedance seems to follow a normal distribution. We have performed a goodnes of fitting test and the better distribution to fit the data of a population is the log-normal distribution. It is interesting to note that our result for skin impedance is in simtony with body impedance from the literature of electrical engeneering. Our results have an impact over the statistical planning and modelling of skin impedance experiments. Special attention we should drive to the treatment of outliers in this kind of dataset. The results of this work are important in the general discussion of low impedance of points of acupuncture and also in the problem of skin biopotentials used in equipments like the Electrodermal Screen Tests.

Aborto em adolesecentes: Ato tão praticado e tão pouco conhecido

O aborto provocado na adolescência como problema de saúde pública, é tema deste estudo que teve como objetivo identificar os motivos que levam adolescentes a provocar o aborto. A multidisciplinariedade do Programa de Pós Graduação em Ciências da Saúde, da Universidade Federal do Rio Grande do Norte, proporcionou o convívio com vários pesquisadores, bem como contribuiu para a coorientação e o crescimento deste estudo e da Pesquisadora com aquisição de conhecimentos diversificados e inovadores. Estudo transversal, quantitativo, analítico, usou questionário semi-estruturado como instrumento que foi aplicado em dez escolas. Trabalhou-se com jovens do sexo feminino, dos 12 aos 19 anos de idade. A amostra representativa foi calculada considerando-se o número de internações por curetagens na cidade de Maceió em 2004. O Banco de Dados foi analisado pelo programa Epi Info versão 3.3.2. Foram usados os testes Quiquadrado, Odds Ratio, Risco Relativo e Regressão Logística. A amostra foi de 2592 jovens, numa distribuição normal, com idade média e mediana de 15 anos, desvio padrão de 1,7. A maioria das jovens era solteira (95,7%), não trabalhava (94,1%), residia com ambos os pais (66,2%) e conhecia algum método contraceptivo (95,5%). Do total das adolescentes estudadas, 52,4% estudava o nível educacional médio. Delas 21,6% tinham vida sexual ativa, 6,4% engravidaram e 5,7 % abortaram. A maioria (95,5%) afirmou conhecer algum método contraceptivo, destas 70,1% tinha mais de 15 anos e os métodos mais citados foram os de barreira/hormonal com 72,4%. Analisando o Risco Relativo observou-se que o risco era significativo e protetor para o começo da vida sexual antes dos 15 anos de idade. Apenas 32,4% delas citaram algum tipo de complicação o aborto. Foi significativa a relação entre a idade e as citações da morte, da esterilidade como a complicação do aborto. A maioria recebeu apoio para abortar (63,8%), amigas foram as que mais apoiaram (32,9%), sendo significativa a relação entre o apoio recebido para abortar e a pratica do ato. O motivo mais citado foi o medo da reação dos pais (57,7%), esteja este motivo apontado como único ou associado a outros. A análise de significância entre as variáveis dicotômicas, forneceu 8 variáveis significativas, 2 protetoras para o abortamento: idade de 12-14 anos e conversar com os pais sobre sexo. As demais variáveis: estado marital com companheiro, vida sexual ativa, gravidez anterior, uso de método contraceptivo, recebimento de apoio para abortar e necessidade de internamento pós-aborto, foram promotoras ao abortamento. Receber apoio para abortar foi a mais significativa para abortar, estado marital com companheiro foi fator de proteção para o ato. Conclui-se que o apoio para abortar foi a variável mais significativa deste estudo reforçando a importância do grupo na adolescência. Sugere-se maior atenção as ações educativas como prevenção para riscos na saúde reprodutiva dos jovens

Síndrome metabólica e fatores associados: estudo comparativo com mulheres que apresentaram pré-eclâmpsia e gravidez normal, acompanhadas cinco anos após o parto

Preeclampsia is defined as an extremely serious complication of the pregnancy-puerperium cycle with delayed emergence of cardiovascular risk factors, including metabolic syndrome. The research aimed estimate the prevalences of metabolic syndrome and associated factors in women with preeclampsia and normal pregnancy followed five years after childbirth. This is a cross-sectional observational study using a quantitative approach, conducted at a maternity school in the city of Natal in Rio Grande do Norte state. The sample was composed of 70 women with previous preeclampsia and 75 normal selected by simple random probability sampling. Subjects were analyzed for sociodemographic, obstetric, clinical, anthropometric and biochemical parameters. International Diabetes Federation criteria were adopted to diagnose metabol ic syndrome. The Kolmogorov-Smirnov, Mann-Whitney, Student s t, Pearson s chi-squared, and Fisher s exact tests, in addition to simple logistic regression, were used for data analysis, at a 5% significance level (p ≤ 0.05). Statistical tests demonstrated elevated body mass index (p = 0.001), predominance of family history of diabetes mellitus (p = 0.022) and significantly higher prevalence of metabolic syndrome in the preeclampsia group (37.1%) when compared to normal (22.7%) (p = 0.042). Intergroup comparison showed a high number of metabolic syndrome components in women with previous preeclampsia. Altered systolic and diastolic blood pressure (p < 0.001) was the most prevalent, followed by low concentrations of high-density lipoproteins (p = 0.049), and hyperglycemia (p=0.030). There was a predominance of the metabolic syndrome in women with schooling 0-9 years (42.4%) (p = 0.005), body mass index above 30Kg.m 2 (52.3%) (p < 0.001), uric acid high (62.5%) (p = 0.050 and family history of hypertension (38.5%) (p< 0.001). Multivariate analysis of the data showed that the body mass index above 30 kg.m2, education level less than 10 years of study (p < 0.001) and family history of hypertension (p = 0.002) remained associated with the metabolic syndrome after multivariate analysis of the data. It is considered Women with previous preeclampsia exhibited high prevalence of metabolic syndrome and their individual components in relation to normal, especially, altered systolic and diastolic blood pressure, low concentrations of high-density lipoproteins and hyperglycemia. The factors associated to this ou tcome were obesity, less than 10 years of schooling, and family history of hypertension. Overall, this study identified young women with a history of PE exposed to a higher cardiovascular risk than normal

Um algoritmo para estimação de estado em alimentadores de distribuição de energia elétrica com base no método da soma de potências

Most algorithms for state estimation based on the classical model are just adequate for use in transmission networks. Few algorithms were developed specifically for distribution systems, probably because of the little amount of data available in real time. Most overhead feeders possess just current and voltage measurements at the middle voltage bus-bar at the substation. In this way, classical algorithms are of difficult implementation, even considering off-line acquired data as pseudo-measurements. However, the necessity of automating the operation of distribution networks, mainly in regard to the selectivity of protection systems, as well to implement possibilities of load transfer maneuvers, is changing the network planning policy. In this way, some equipments incorporating telemetry and command modules have been installed in order to improve operational features, and so increasing the amount of measurement data available in real-time in the System Operation Center (SOC). This encourages the development of a state estimator model, involving real-time information and pseudo-measurements of loads, that are built from typical power factors and utilization factors (demand factors) of distribution transformers. This work reports about the development of a new state estimation method, specific for radial distribution systems. The main algorithm of the method is based on the power summation load flow. The estimation is carried out piecewise, section by section of the feeder, going from the substation to the terminal nodes. For each section, a measurement model is built, resulting in a nonlinear overdetermined equations set, whose solution is achieved by the Gaussian normal equation. The estimated variables of a section are used as pseudo-measurements for the next section. In general, a measurement set for a generic section consists of pseudo-measurements of power flows and nodal voltages obtained from the previous section or measurements in real-time, if they exist -, besides pseudomeasurements of injected powers for the power summations, whose functions are the load flow equations, assuming that the network can be represented by its single-phase equivalent. The great advantage of the algorithm is its simplicity and low computational effort. Moreover, the algorithm is very efficient, in regard to the accuracy of the estimated values. Besides the power summation state estimator, this work shows how other algorithms could be adapted to provide state estimation of middle voltage substations and networks, namely Schweppes method and an algorithm based on current proportionality, that is usually adopted for network planning tasks. Both estimators were implemented not only as alternatives for the proposed method, but also looking for getting results that give support for its validation. Once in most cases no power measurement is performed at beginning of the feeder and this is required for implementing the power summation estimations method, a new algorithm for estimating the network variables at the middle voltage bus-bar was also developed

Distribuição diária do comportamento da mosca da fruta Anastrepha zenildae Zucchi, (Diptera: Tephritidae) em laboratório.

The knowledge of Anastrepha zenildae behavioral aspects combined with the biology of Tephritidae may contribute to monitoring and control programs of this fruit fly that is considered as economically important to the Rio Grande do Norte state. In order to characterize the daily activity profile of this species, we studied the behaviors of resting, locomotion, feeding, cleaning, courtship, copulation and oviposition of animals submitted to an artificial 12:12h light-dark cycle (750:1lux) with controlled temperature (26±2 °C). The observations were made with groups of 16 males and 16 females during 3 consecutive days each generation from parental to F5. Resting, locomotion, feeding and cleaning data were recorded as frequency and time of occurrence by scanning technique in 15 minutes windows per hour, with a record each minute. Courtship, copulation and oviposition were recorded as frequency, time of occurrence and duration by al occurrences technique. Resting was the most frequent behavior with males resting more than females. Locomotion was more evident in the first half of the ligh phase with higher values in females. Cleaning and feeding behaviors were more frequent in the second half of the light phase for both sexes with females eating more frequently than males. During the courtship, males were grouped in lek formations showing wings vibration and pheromone liberation. Courtship occurred more frequently 4 to 7 h after lights on (81,9%) with copulations being more frequent 6 h after lights on with a mean duration of 58,1±40,4 min. Copulation attempts were observed in males inside and outside the lek with aggressive behavior being observed only between males in the lek. Oviposition behavior was similar to that described for other species of the genus with a peak of this activity 2-3 h after the lights on, mean duration of 43, 7±34, 8 sec and 2 to 5 eggs by event. According to the results, sexual behavior of A. zenildae is temporally different of other sympatric species of the genus, being favorable to the reproductive isolation as well as the use of resources as oviposition substrate.

Estudo da atividade sísmica em São Caetano-PE em 2007

In this dissertation we studied the seismic activity in the São Caetano county, Pernambuco State, Northeastern Brazil, located near the Pernambuco Lineament. The Pernambuco Lineament is a one of Neoproterozoic continental-scale shear zones that deforms the Borborema province. The seismicity estudied occurred in a NE trending branch of Pernambuco Lineament. The seismic activity in São Caetano started in 2006 and in May 20th, 2006 a 4,0 mb earthquake hit there. This was the largest earthquake ever reported in Pernambuco State. This dissertation is the result of a campaign done in the period from Februay 1th 2007 to July 31 th 2007. In this campaign up to nine three-component digital seismographic stations were deployed and the collected data was used to determine hypocenters and focal mechanism. A total of 214 earthquakes, recorded at least by three stations, were analyzed. To determine hypocenters and time origin the HYPO71 program was used assuming a half-space model with parameters : VP (P-wave velocity) equal to 5.90 km/s and the ratio VP/VS 1.70, where VS is the S-wave velocity. The earthquakes hypocentral distribution was approximately 4 km long and agrees with the NE-SW direction of the Pernambuco Lineamento branch. Hypocentres depth range from 2 to 8 km. The composed focal mechanism was made from a group of 14 selected earthquakes. We try firstly to find the fault plane solution matching the polarity distribution at stations, using the FPFIT program. The result was 43 deg ± 15 deg for strike, 59 deg ± 9 deg for dip and -142 deg ± 15 deg for rake. We also fitted a plane using the hypocentral distribution to obtain the dip and azimuth of the hypocentral distribution. The results obtained by this fit were 58 deg for the azimuth, 55 deg for the dip and -155 deg for rake. This result shows a mechanism of a strike-slip dextral fault with a normal component. This dissertation shows, once more, that there is a good correlation between the seismic activity and geological features in the region near the Pernambuco Lineament and its NE branches

Arquitetura, litofácies e evolução tectonoestratigráfica da bacia do rio do peixe, nordeste do Brasil

The Rio do Peixe Basin is located in the border of Paraíba and Ceará states, immediately to the north of the Patos shear zone, encompassing an area of 1,315 km2. This is one of the main basins of eocretaceous age in Northeast Brazil, associated to the rifting event that shaped the present continental margin. The basin can be divided into four sub-basins, corresponding to Pombal, Sousa, Brejo das Freiras and Icozinho half-grabens. This dissertation was based on the analysis and interpretation of remote sensing products, field stratigraphic and structural data, and seismic sections and gravity data. Field work detailed the lithofacies characterization of the three formations previously recognised in the basin, Antenor Navarro, Sousa and Rio Piranhas. Unlike the classical vertical stacking, field relations and seismostratigraphic analysis highlighted the interdigitation and lateral equivalency between these units. On bio/chrono-stratigraphic and tectonic grounds, they correlate with the Rift Tectonosequence of neocomian age. The Antenor Navarro Formation rests overlies the crystalline basement in non conformity. It comprises lithofacies originated by a braided fluvial system system, dominated by immature, coarse and conglomeratic sandstones, and polymict conglomerates at the base. Its exposures occur in the different halfgrabens, along its flexural margins. Paleocurrent data indicate source areas in the basement to the north/NW, or input along strike ramps. The Sousa Formation is composed by fine-grained sandstones, siltites and reddish, locally grey-greenish to reddish laminated shales presenting wavy marks, mudcracks and, sometimes, carbonate beds. This formation shows major influence of a fluvial, floodplain system, with seismostratigraphic evidence of lacustrine facies at subsurface. Its distribution occupies the central part of the Sousa and Brejo das Freiras half-grabens, which constitute the main depocenters of the basin. Paleocurrent analysis shows that sediment transport was also from north/NW to south/SE

Distribuição socioespacial dos fatores dinâmicos da população na Região Metropolitana de Natal

The Metropolitan Region of Natal, like other metropolitan regions in Brazil, was marked by intense and rapid urbanization of the country occurred only in the second half of the twentieth century, coinciding with the process of consolidation of the industry in the country, resulting in serious urban social problems, such as the increase in slums, lack of infrastructure and this increase in violence in urban centers. When enters the reality of the metropolitan region, assessing the impacts of restructuring productive in the context of globalization, analyzing how the socio-economic factors influencing the dynamic of the population, whose configuration was shown to be contradictory according to social class busy. Accordingly, we studied the demographic configuration of the Metropolitan Region of Natal, analyzing their spatial distribution and their socio-demographic differences in light of building a type socio-space, which cuts the metropolitan space in homogeneous areas

Modelos de dispersão para extremos de precipitação. Estudo de caso: o nordeste do Brasil

In this thesis used four different methods in order to diagnose the precipitation extremes on Northeastern Brazil (NEB): Generalized Linear Model s via logistic regression and Poisson, extreme value theory analysis via generalized extre me value (GEV) and generalized Pareto (GPD) distributions and Vectorial Generalized Linea r Models via GEV (MVLG GEV). The logistic regression and Poisson models were used to identify the interactions between the precipitation extremes and other variables based on the odds ratios and relative risks. It was found that the outgoing longwave radiation was the indicator variable for the occurrence of extreme precipitation on eastern, northern and semi arid NEB, and the relative humidity was verified on southern NEB. The GEV and GPD distribut ions (based on the 95th percentile) showed that the location and scale parameters were presented the maximum on the eastern and northern coast NEB, the GEV verified a maximum core on western of Pernambuco influenced by weather systems and topography. The GEV and GPD shape parameter, for most regions the data fitted by Weibull negative an d Beta distributions (ξ < 0) , respectively. The levels and return periods of GEV (GPD) on north ern Maranhão (centerrn of Bahia) may occur at least an extreme precipitation event excee ding over of 160.9 mm /day (192.3 mm / day) on next 30 years. The MVLG GEV model found tha t the zonal and meridional wind components, evaporation and Atlantic and Pacific se a surface temperature boost the precipitation extremes. The GEV parameters show the following results: a) location ( ), the highest value was 88.26 ± 6.42 mm on northern Maran hão; b) scale ( σ ), most regions showed positive values, except on southern of Maranhão; an d c) shape ( ξ ), most of the selected regions were adjusted by the Weibull negative distr ibution ( ξ < 0 ). The southern Maranhão and southern Bahia have greater accuracy. The level period, it was estimated that the centern of Bahia may occur at least an extreme precipitatio n event equal to or exceeding over 571.2 mm/day on next 30 years.