82 resultados para Seleção Variáveis Observadas

em Universidade Federal do Rio Grande do Norte(UFRN)


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The interest in the systematic analysis of astronomical time series data, as well as development in astronomical instrumentation and automation over the past two decades has given rise to several questions of how to analyze and synthesize the growing amount of data. These data have led to many discoveries in the areas of modern astronomy asteroseismology, exoplanets and stellar evolution. However, treatment methods and data analysis have failed to follow the development of the instruments themselves, although much effort has been done. In present thesis, we propose new methods of data analysis and two catalogs of the variable stars that allowed the study of rotational modulation and stellar variability. Were analyzed the photometric databases fromtwo distinctmissions: CoRoT (Convection Rotation and planetary Transits) and WFCAM (Wide Field Camera). Furthermore the present work describes several methods for the analysis of photometric data besides propose and refine selection techniques of data using indices of variability. Preliminary results show that variability indices have an efficiency greater than the indices most often used in the literature. An efficient selection of variable stars is essential to improve the efficiency of all subsequent steps. Fromthese analyses were obtained two catalogs; first, fromtheWFCAMdatabase we achieve a catalog with 319 variable stars observed in the photometric bands Y ZJHK. These stars show periods ranging between ∼ 0, 2 to ∼ 560 days whose the variability signatures present RR-Lyrae, Cepheids , LPVs, cataclysmic variables, among many others. Second, from the CoRoT database we selected 4, 206 stars with typical signatures of rotationalmodulation, using a supervised process. These stars show periods ranging between ∼ 0, 33 to ∼ 92 days, amplitude variability between ∼ 0, 001 to ∼ 0, 5 mag, color index (J - H) between ∼ 0, 0 to ∼ 1, 4 mag and spectral type CoRoT FGKM. The WFCAM variable stars catalog is being used to compose a database of light curves to be used as template in an automatic classifier for variable stars observed by the project VVV (Visible and Infrared Survey Telescope for Astronomy) moreover it are a fundamental start point to study different scientific cases. For example, a set of 12 young stars who are in a star formation region and the study of RR Lyrae-whose properties are not well established in the infrared. Based on CoRoT results we were able to show, for the first time, the rotational modulation evolution for an wide homogeneous sample of field stars. The results are inagreement with those expected by the stellar evolution theory. Furthermore, we identified 4 solar-type stars ( with color indices, spectral type, luminosity class and rotation period close to the Sun) besides 400 M-giant stars that we have a special interest to forthcoming studies. From the solar-type stars we can describe the future and past of the Sun while properties of M-stars are not well known. Our results allow concluded that there is a high dependence of the color-period diagram with the reddening in which increase the uncertainties of the age-period realized by previous works using CoRoT data. This thesis provides a large data-set for different scientific works, such as; magnetic activity, cataclysmic variables, brown dwarfs, RR-Lyrae, solar analogous, giant stars, among others. For instance, these data will allow us to study the relationship of magnetic activitywith stellar evolution. Besides these aspects, this thesis presents an improved classification for a significant number of stars in the CoRoT database and introduces a new set of tools that can be used to improve the entire process of the photometric databases analysis

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Objective: Identify phenotype and genotype parameters of female volleyball players at different performance levels to help in player selection. Methods: We identified characteristics of phenotype and genotype using the somatotype method (Heath Carter); anthropometry (weight, height and fat percentage); dermatoglyphics (Cummins and Midlo s method) as well as applying physical quality tests (Shuttle Run to assess agility and the Sargent Jump Test adapted for spike and block reach). The sample was composed of 179 players (54 from national teams and 125 from state teams). Results: Somatotype was similar among the performance levels in the mesomorphic component. The Height and ectomorphic component were greater in national team players as was spike and block reach. The vertical jump height for the spike was similar between the national under-17 team and the state teams observed, but in the block jump the lower level players were better. The dermatoglyphics characteristics identified were similar among the groups studied. Conclusions: The results of the variables studied show that somatotype, height, spike reach and block reach are fundamental parameters in player selection and in the specific characteristics of each game position of this sport. This paper proposes a multidisciplinary approach applicable in the fields of physical education, medicine and nutrition

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The methods of analysis of the selection system sports talent sometimes do not consider the biological age of the athletes, since that the assessment of maturational moment have several limitations The aim of this work is to develop a predictive equation of pubertal assessment in male subjects, based on anthropometric measurements. We evaluated 206 young boys, aged between eight and 18 years, and studing in public and private schools in Natal, Brazil. The sample selection was done randomly, being used the anthropometric measurements and pubertal maturation evaluation according to the Tanner stages. Statistical analysis followed the presentation of central tendency measures and their derivatives. The inferential analysis was performed according to the ANOVA test, multivariate discriminant analysis and weighted Kappa. The advancement of pubertal stages was accompanied by significant changes in anthropometric variables, demonstrating the relationship presented in both. For this purpose, discriminant analysis selected eight variables with the highest prediction of pubertal maturation, and created an equation with a significance level of 75%. and concordance level of 0.840, considered as excellent. This shows that the prediction of pubertal maturation from anthropometric variables presented as a valid method, being used as a practical tool in sports talents selection

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Introduction: The reference values and prediction equations for maximal respiratory pressures (MRP) differ significantly between the available studies. This large discrepancy can be attributed to the different methodologies proposed. Although the importance of MRP is widely recognized, there are no Brazilian studies that provide predictive equations and reference values for PRM adolescents. Objectives: The purpose of this study was to provide normal values and propose predictive equations for maximal static respiratory pressures of Brazilian adolescents. Methods: An observational cross-sectional study, which evaluated 182 adolescents of both sexes aged between 12 and 18 years, enrolled in schools of the state and private in the city of Natal / RN. The selection of schools and participants of the study was randomly through a lottery system. The spirometric evaluation was performed through the digital spirometer One Flow FVC prior to the assessment of respiratory muscle strength. The MICs were measured with MVD digital manometer 300. Statistical analysis was performed using the SPSS 17.0 software STATISTICS, assigning the significance level of 5%. The normality of data distribution was verified using the Kolmogorov-Smirnov (KS). The descriptive analysis was expressed as mean and standard deviation. We used one-way ANOVA test to verify the difference of the averages of MRPs between age and gender and comparing the averages of MRPs between levels of physical activity. The test t'Student unpaired compared the averages of MRPs being ages and sexes. The comparison of mean values obtained in this study PRM with the values predicted using the equations mentioned above was relizada by testing paired t'Student. To verify the correlation between the PRM and the independent variables (age, weight, height) was used Pearson correlation test. Levene's test evaluated the homogeneity of variance. To obtain predictive equations analysis was used stepwise multiple linear regression. Results: There was no significant difference in mean age between the PRM. The male adolescents, regardless of age, showed superiority in MRP values when compared to the opposite sex. Weight, height and sex correlated with the PRM. Regression analysis suggested in this study, pointed out that the weight and sex had an influence in MIP and MEP only in relation to sex influenced. The mean for each PRM adolescents classified as very active were superior to those observed in adolescents classified as irregularly active. Conclusion: This study provides reference values and two models of predictive equations for maximal inspiratory and expiratory pressures, and to establish the lower limits of normality that will serve as an indispensable condition for careful evaluation of respiratory muscle strength in Brazilian adolescents

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A obesidade é uma epidemia global em alarmante ascensão. Caracterizada pelo excesso de gordura corporal subcutânea, de caráter multifatorial, está relacionada ao surgimento de diversas co-morbidades, entre elas, várias alterações respiratórias, estas se tornam mais intensas quanto maior o grau de obesidade. Não há consenso na relação entre os marcadores de adiposidade geral ou específicos e suas repercussões sobre a função ventilatória, especialmente em relação à sobrecarga muscular respiratória. Objetivo: Analisar a relação entre marcadores antropométricos e variáveis espirométricas e de força muscular respiratória em indivíduos com obesidade mórbida. Métodos: Estudo transversal entre setembro de 2007 e outubro de 2012. Participaram da pesquisa 163 obesos mórbidos (37.1±9.8 anos e IMC=49.0±5.88 Kg/m2) sem alterações espirométricas. Foram observadas as associações entre Índice de Massa Corporal-IMC, adiposidade localizada (Circunferências de Pescoço-CP, Cintura-CC e Quadril-CQ), percentual de gordura corporal através do Índice de Adiposidade Corporal-IAC, volumes e capacidades pulmonares (CVF, VEF1 e VRE) e pressões respiratória estática (PIM e PEM) e dinâmica (VVM). Resultados: O VRE foi o volume mais afetado pela obesidade (apenas 41%predito) e mostrou associação negativa nas relações com todos os marcadores de adiposidade (IMC: r=-0.52; IAC: r=-0.21; CC: r=-0.44; CP: r=-0.25 e CQ: r=-0.28). Há relação inversa entre o percentual de gordura corporal (IAC) com a CVF (r=-0.59), o VEF1(r=-0.56) e o VVM (r=-0.43). As pressões respiratórias são justificadas principalmente pela adiposidade ao redor do pescoço e o IAC. Nossos dados de força muscular respiratória foram melhores associados aos valores de referências sugeridos pelas equações de Harik-Klan et al (1998) para PIM (R²=0.72) e com a equação proposta por Neder et al (1999) para PEM (R²=0.52). Em um modelo de regressão linear, as variáveis de adiposidade não justificam a VVM, já o VEF1 explica 62% da variância da VVM em obesos mórbidos. Conclusão: O percentual da adiposidade corporal e a circunferência do pescoço estão associados com a força muscular e capacidade de gerar fluxo respiratório de obesos mórbidos. Sugerimos a equação elaborada por Harik-Klan et al (1998) para obtenção de valores preditos de PIM e a equação proposta por Neder et al (1999) para valores de normalidade da PEM em sujeitos com obesidade mórbida. Foi possível fornecer uma equação de referência específica para VVM em obesos mórbidos

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Natural selection shapes body and behavior of each species. For primates, the social environment constituted one of the greatest selective pressure for the development of their cognition. When we consider gender differences, we see that sexual selection also operates through different selective pressures for men and women not only in physical terms but in terms of cognitive skills. Among these, the primary cognitive abilities - that emerge naturally - and secondary - that rely on an artificial environment for learning - develop differently for each sex, making them suitable for specific tasks in different capacities. Previous studies utilized the Wason Selection Test a conditional logic tool - to measure, among several other things, the ability to recognize violation of rules in abstract contexts and social contexts. Subjects generally had better performance in the latter, however, in these studies possible differences motivated by learning in formal logic or genre were not considered. Our study investigated these two variables, as well as the time spent to solve each task. Furthermore, we used an index to take into account the rights and wrongs of the participants in tasks. We realized that although learning in formal logic does not bring significant differences in solving tests, the gender differences are strongly observed when we consider the social contexts and abstract. Women perform better in social tasks. This can be explained due to different sexual selective pressures for this gender in terms of one-on-one relationships within the group. Men are better at tasks of abstract context and this is probably due to the same reason. Their capabilities for territory defense, habitat navigation and forming coalitions depends on primary cognitive abilities that support secondary cognitive skills of abstraction. Thus, gender differences are a factor to be taken into account in controlling future experiments with the same tool

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This study deals with cognitive competences and abilities that are relevant to selection and education regarding Information Technology (IT). These competences relate to problem solving, decision making, and practical intelligence that regard scholar and extracurricular knowledge mobilization. The research aimed to contribute for the improvement of a selection instrument, consisting of five arrays of skills (dealing with objectives and prospection), as well as the development and comprehension of those skills that are involved in IT education. This is done by means of an analysis on the selection instrument used in the first selective process that occurred at Metropole Digital an Institute at the Federal University of Rio Grande do Norte in Brazil. This was evaluated aiming to acknowledge IT education (with basic training and emphasis on Web programming and electronics). The methodology used was of quantitative method involving performance scores relating education delivery. An Anova analysis of variance was done along with descriptive analysis involving socioeconomic data that was not observed in the meaningful relations between parental instruction and student performance in the graduate course. These analyses were able to point out the importance and need of the policies for vacancy reservation on behalf of public school students. A Spearman correlation analysis was done considering the instrument selection performance in the training course. The instrument is presented as a predictor that is significantly moderate and presents a good performance in the course as a whole. A Cluster and Regression analysis was also realized in the process. The first analysis allowed finding performance groups (Clusters) that ranged from medium and inferior. The regression analysis was able to point out association amongst criterion variables and the (average performance in basic and advanced modules) and explanatory (five matrixes). Regression analysis indicated that matrix 1 and matrix 3 were pointed out as being the strongest ones. In all the above analysis, the correlation between the instrument and the course was considered moderate. Thus this can be related in some of the aspects present in the course such as emphasis on evaluation itself as well as in technical contents and practical skills (educational ones) and competences and selection skills. It is known that the mediation of technological artifact in cultural context can foster the development of skills and abilities relevant to IT training. This study provides subsidies to reflect on the adoption of selection instrument and IT training in the Institute. Thus the research offers means to achieve a interdisciplinary discussion and enriching of areas such as Psychology and Information Technology; all of which regarding competencies and skills relevant in IT training

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The aim of this study was to evaluate the potential of near-infrared reflectance spectroscopy (NIRS) as a rapid and non-destructive method to determine the soluble solid content (SSC), pH and titratable acidity of intact plums. Samples of plum with a total solids content ranging from 5.7 to 15%, pH from 2.72 to 3.84 and titratable acidity from 0.88 a 3.6% were collected from supermarkets in Natal-Brazil, and NIR spectra were acquired in the 714 2500 nm range. A comparison of several multivariate calibration techniques with respect to several pre-processing data and variable selection algorithms, such as interval Partial Least Squares (iPLS), genetic algorithm (GA), successive projections algorithm (SPA) and ordered predictors selection (OPS), was performed. Validation models for SSC, pH and titratable acidity had a coefficient of correlation (R) of 0.95 0.90 and 0.80, as well as a root mean square error of prediction (RMSEP) of 0.45ºBrix, 0.07 and 0.40%, respectively. From these results, it can be concluded that NIR spectroscopy can be used as a non-destructive alternative for measuring the SSC, pH and titratable acidity in plums

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BRUNO, S. S. ; SOUSA, M. B. C. . Modulação pela progesterona da sensibilidade dolorosa a estímulos mecânicos e isquêmicos em mulheres saudáveis e jovens. RBGO. Revista Brasileira de Ginecologia e Obstetrícia , v. 30, p. 306-311, 2008

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MEDEIROS, Ana Luiza. Seleção e formação de coleções de obras raras: da ordenação do saber à pratica cultural. In: CONGRESSO BRASILEIRO DE BIBLIOTECONOMIA, DOCUMENTAÇÃO E CIÊNCIA DA INFORMAÇÃO, 24., Maceió, 2011. Anais... Maceió: FEBAB, 2011.

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Neste trabalho objetivou-se verificar, teoricamente , a possibilidade de manutenção de heterozigotos, em populações de plantas autógamas, na presença e na ausência de seleção dependente de frequência (SDF). Considerou-se apenas um loco com dois alelos. Utilizou-se a dedução algébrica de formulas referentes a alguns modelos de populações e um programa para simular a sucessão das gerações em uma calculadora científica avançada. Comparou-se os resultados do modelo com os dados obtidos experimentalmente por Allard e Workman (1963) e por Harding, Allard e Smeltzer (1966). Os coeficientes de determinação foram 0,9653 e 0,9166 para a primeira e a segunda comparação, respectivamente. Estes coeficientes indicam que o modelo D representa de modo bastante fidedigno as variações observadas em populações experimentais de plantas predominantemente autógamas

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Analisar, em pacientes submetidos a simpaticotomia videotoracoscópica para tratamento da Hiperidrose Primária (HP), as conseqüências hemodinâmicas da desnervação vascular das artérias carótidas e vertebrais após a trans-secção cirúrgica da cadeia simpática torácica (simpaticotomia), através da mensuração de parâmetros ultra-sonográficos. Método: Vinte e quatro pacientes portadores de HP submetidos a quarenta e oito simpaticotomias torácicas endoscópicas foram avaliados através da mensuração da velocidade de pico sistólico (VPS), velocidade de pico diastólico (VPD), índice de pulsatibilidade (IP) e índice de resistência (IR) nas artérias carótidas comuns, internas e externas, além da artéria vertebral bilateralmente usando o eco-doppler duplex scan. As avaliações foram realizadas antes da intervenção cirúrgica e trinta dias após o procedimento. O teste de Wilcoxon foi usado na análise das diferenças entre as variáveis antes e depois da simpaticotomia. Resultados: A simpaticotomia no nível de T3 foi a trans-secção mais realizada (95,83%), seja isoladamente (25%) ou associada a T4 (62,50%) ou a T2 (8,33%). Houve aumento significativo no IR e no IP da artéria carótida comum bilateralmente (p<0,05). A VPD da artéria carótida interna diminuiu em ambos os lados (p<0,05). A VPS e a VPD da artéria vertebral direita também aumentaram (p<0,05). Achados assimétricos foram observados, de modo que artérias do lado direito foram as mais freqüentemente afetadas. Conclusões: Alterações hemodinâmicas foram observadas nas artérias vertebral e carótida após simpaticotomia para tratamento de HP. VPS foi o parâmetro mais freqüentemente alterado, principalmente nas artérias do lado direito, representando alterações assimétricas significantes nas artérias carótida e vertebral. Entretanto, são necessárias pesquisas subseqüentes para verificar se essas alterações são definitivas ou temporárias, uma vez que as inferências clínicas somente terão validação se as alterações forem permanentes

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This paper comprises an investigation on the influence of the variable family backgrounds (father school level, mother school level and family income) over the pupil s performance in admissions examination (entrance test or PROITEC) at Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Norte (IFRN). From that point of view, the main goal of this research is to analyze the influence of the family background as a determiner of the pupil´s performance in the access to Technical and Professional education at IFRN. Secondary data were used from two databases (entrance test and PROITEC) adding up to 19.226 observations to the vacancies offered in the year of 2013. Aiming at achieving the proposed goal, a conceptual model composed of three hypothesis was developed. The results were presented in four stages: stage I presentation of the descriptive statistical results of the two databases; stage II separation of the campi in clusters; stage III analysis of multiple regressions; stage IV analysis of the logistics regressions. Two statistical tests were used to validate the hypothesis: T-test and Wald test. Hypothesis 1 and 2 were confirmed and H3 was refused. The results presented favorable causal connections to the family income and the father school level variables (with bigger effect for fathers with a higher education degree). The mother school level variable did not provide statistical significance for this research. Based on this result, after this work, this institution is to develop a strategic plan to assist in the success rate of students preparing diagnoses in order to diminish the effects of the variables that impacted negatively

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This master thesis aims to assess the influence of the design decisions on the energy building performance of hotels. The research is based on the integration of field study and computer simulation. Firstly, a detailed field study is carried out to identify the characteristics of hotels in Natal, Rio Grande do Norte. The items assessed are occupancies, light and equipment densities, types of air conditioning, total and monthly energy consumption, among others. A second and more comprehensive field study is carried out to identify the range of occurrence of architectural variables, with a larger number of buildings. A base case is modelled in VisualDOE, based on the first field study. Then, a first set of simulations are run to explore the sensitivity of the variables on the energy consumption. The results analyses were the base of a second set of simulations, which combined the most influential variables. The results of 384 models were assessed, and the impacts of design decisions were quantified. The study discusses tendencies and recommendations, as well as the methods advantages and disadvantages

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Dentre as macroalgas capazes de absorver altas concentrações de N e P dissolvidos na água, destaca-se a Chlorophyta Ulva lactuca, bastante adaptável e resistente às adversidades ambientais, como grandes variações de temperatura, salinidade, matéria orgânica e metais pesados. Trata-se também de uma espécie bastante comum nas áreas intertidais do litoral norte-riograndense. Devido a suas características ecológicas, fisiológicas e nutricionais, foi avaliado nesse estudo, o seu potencial como biofiltro na redução de NH4+, NO3- e PO4-2, tanto em condições controladas como também em um viveiro de camarão. No experimento laboratorial, foram utilizados quatro aquários de vidro de 30 x 20 x 20cm com 10L de água, sendo três aquários experimentais contendo 20g de U. lactuca e um controle. O acréscimo de biomassa foi de 2,92g (22,92 ± 6,29g; p < 0,05) em relação ao inóculo inicial de 20g, sob temperatura (28,50 ± 0,58ºC), salinidade (35,00 ± 0,00 ), pH (8,26 ± 0,02) e luz constante (250 μmol.m2s-1). O crescimento positivo (1,78 ± 4,38%dia-1; p < 0,05), juntamente com a alta eficiência de absorção de amônio (83%; p < 0,001), nitrato (83%; p < 0,001) e ortofosfato (53%; p < 0,001), demonstrou que, nessas condições, a Ulva lactuca absorveu os nutrientes e aumentou sua biomassa. Já no experimento de campo, realizado na fazenda TECNARÃO, situada no município de Arez/RN (06° 11 40 Latitude Sul, e 35º 09 37 Longitude Oeste), foram utilizadas três gaiolas de PVC, posicionadas a 12cm da superfície da água, cada uma com dimensões de aproximadamente 59 x 59 x 15cm, onde foram colocadas 200g de U. lactuca. O ganho de biomassa de 3g (203,00 ± 41,02g; p < 0,001) foi muito semelhante às condições controladas, demonstrando a adaptabilidade da espécie em condições ambientais variáveis, onde, apesar da temperatura pouco variável (27,45 ± 0,64ºC), houve progressiva diminuição de salinidade (25 - 15 ), devido ao período de fortes chuvas (34,70 ± 23,78mm). Somado a isso, foram observados vários fatores biológicos interferindo no viveiro, como a presença de epífitas, organismos endofíticos, fouling e a herbivoria por parte dos próprios camarões. Houve aumento nas concentrações de NH4+ (4,36 ± 1,69 μmol.L-1), NO3- (0,17 ± 0,25μmol.L-1) e PO4-2 (0,41 ± 0,13μmol.L-1), coincidindo com o crescimento da espécie até a terceira semana. Todos os parâmetros ambientais analisados, assim como a biomassa e a Taxa de Crescimento Relativo (TCR), obtidos no campo, apresentaram variações altamente significativas (p < 0,001). As correlações observadas entre biomasa e NH4+ (r = 0,82; p < 0,001) e entre biomassa e PO4-2 (r = 0,87; p < 0,001), indicam que esta espécie é capaz de ter um crescimento satisfatório nas condições eutróficas de um viveiro de camarão, sendo possível seu uso como biofiltro.