801 research outputs found

    DESENVOLVIMENTO E VALIDAÇÃO DE UM DISPOSITIVO PARA MENSURAÇÃO DA FLEXIBILIDADE POR MEIO DO ACELERÔMETRO EM CRIANÇAS

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    The objectives of this study were to develop and validate a computerized device to measure joint flexibility; to measure flexibility in children in elementary school aged 8 to 10 years using the Wells bank; to compare the data obtained by the Wells bank and the computerized device developed in the present study and evaluate the usability of the device. 215 volunteers participated in this research, aged between 8 and 10 years, 63.72% (137) were female and 36.28% (78) were male, duly enrolled in an educational institution in the Alto Tietê region. For data collection, the volunteers performed the flexibility test using the Wells bank and the computerized device developed in this research to assess flexibility. The computerized device it was made on a 3D printing technology printer. A usability evaluation was carried out with 15 Physical Education teachers for the product developed through a usability questionnaire based on the System Usability Scale (SUS) form, which contains 10 multiple-choice questions. The data obtained by the objective measures determined were evaluated in terms of frequency, mean and standard deviation. The arithmetic means of the three measurements performed at each stage were calculated. Mann-Whitney and Kruskal-Wallis tests and Spearman's correlation were performed for the investigation. For all analyses, significant differences were considered p<0.05. It is concluded that the computerized device to measure joint flexibility is capable of evaluating the range of motion in degrees, and was qualified as easy to handle by professionals in the field of physical education.Los objetivos de este estudio fueron desarrollar y validar un dispositivo computarizado para medir la flexibilidad articular; medir la flexibilidad en niños en la escuela primaria de 8 a 10 años a través del banco Wells; comparar los datos obtenidos por la base de datos Wells y el dispositivo computarizado desarrollado en el presente estudio y evaluar la usabilidad del dispositivo. Un total de 215 voluntarios participaron en esta investigación, con edades de 8 a 10 años, 63,72% (137) mujeres y 36,28% (78) hombres, debidamente matriculados en una institución educativa de la región del Alto Tietê. Para la recolección de datos, los voluntarios realizaron la prueba de flexibilidad utilizando la base de datos Wells y el dispositivo computarizado desarrollado en esta investigación para evaluar la flexibilidad. El dispositivo fue hecho de una impresora de tecnología de impresión 3D. Se realizó una evaluación de usabilidad con 15 profesores de Educación Física para el producto desarrollado a través del cuestionario de usabilidad basado en el formulario System Usability Scale (SUS) que contiene 10 preguntas de opción múltiple. Los datos obtenidos por las mediciones objetivas determinadas fueron evaluados para la frecuencia, media y desviación estándar. Se calcularon las medias aritméticas de las tres mediciones realizadas en cada etapa. Las pruebas de Mann-Whitney y Kruskal-Wallis y la correlación de Spearman se realizaron para la investigación. Para todos los análisis, se consideraron diferencias significativas p<0,05. Se concluye que el dispositivo computarizado para medir la flexibilidad articular es capaz de evaluar el rango de movimiento en grados, y fue calificado fácil de manejar por profesionales de la educación física.Os objetivos deste estudo foram desenvolver e validar um dispositivo computadorizado para mensurar a flexibilidade articular; mensurar a flexibilidade em crianças no ensino fundamental de 8 a 10 anos por meio do banco de Wells; comparar os dados alcançados pelo banco de Wells e o dispositivo computadorizado desenvolvido no presente estudo e avaliar a usabilidade do dispositivo. Participaram desta pesquisa 215 voluntários, com idade de 8 a 10 anos, sendo 63,72% (137) do sexo feminino e 36,28% (78) do sexo masculino, devidamente matriculados em uma instituição de ensino na região do Alto Tietê. Para coleta de dados, os voluntários realizaram o teste de flexibilidade utilizando o banco de Wells e o dispositivo computadorizado desenvolvido nessa pesquisa para avaliar a flexibilidade.O dispositivo foi confeccionado numa impressora de tecnologia de impressão 3D. Foi realizada uma avaliação da usabilidade com 15 professores de Educação Física para o produto desenvolvido através da interação de usabilidade baseada no formulário System Sustainability Scale (SUS) que contém 10 questões de múltipla-escolha. Os dados obtidos por medidas objetivas determinadas foram avaliadas quanto à frequência, média e desvio padrão. Foram seguidas como médias aritméticas das três medidas realizadas em cada etapa. Para investigar realizou-se os testes de Mann-Whitney e de Kruskal-Wallis e a tradução de Spearman. Para todas as análises foram consideradas diferenças significativas p<0,05.Conclui-se que o dispositivo computadorizado para medir a flexibilidade articular é capaz de avaliar em graus a amplitude de movimento

    Very Low Mass Stellar and Substellar Companions to Solar-Like Stars From MARVELS V: A Low Eccentricity Brown Dwarf from the Driest Part of the Desert, MARVELS-6b

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    We describe the discovery of a likely brown dwarf (BD) companion with a minimum mass of 31.7 +/- 2.0 M_Jup to GSC 03546-01452 from the MARVELS radial velocity survey, which we designate as MARVELS-6b. For reasonable priors, our analysis gives a probability of 72% that MARVELS-6b has a mass below the hydrogen-burning limit of 0.072 M_Sun, and thus it is a high-confidence BD companion. It has a moderately long orbital period of 47.8929 +0.0063/-0.0062 days with a low eccentricty of 0.1442 +0.0078/-0.0073, and a semi-amplitude of 1644 +12/-13 m/s. Moderate resolution spectroscopy of the host star has determined the following parameters: T_eff = 5598 +/- 63, log g = 4.44 +/- 0.17, and [Fe/H] = +0.40 +/- 0.09. Based upon these measurements, GSC 03546-01452 has a probable mass and radius of M_star = 1.11 +/- 0.11 M_Sun and R_star = 1.06 +/- 0.23 R_Sun with an age consistent with less than ~6 Gyr at a distance of 219 +/- 21 pc from the Sun. Although MARVELS-6b is not observed to transit, we cannot definitively rule out a transiting configuration based on our observations. There is a visual companion detected with Lucky Imaging at 7.7 arcsec from the host star, but our analysis shows that it is not bound to this system. The minimum mass of MARVELS-6b exists at the minimum of the mass functions for both stars and planets, making this a rare object even compared to other BDs.Comment: 15 pages, 15 figures, 5 tables. Accepted for publication in The Astronomical Journa

    Very Low-Mass Stellar and Substellar Companions to Solar-Like Stars from MARVELS I: A Low Mass Ratio Stellar Companion to TYC 4110-01037-1 in a 79-day Orbit

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    TYC 4110-01037-1 has a low-mass stellar companion, whose small mass ratio and short orbital period are atypical amongst solar-like (Teff ~< 6000 K) binary systems. Our analysis of TYC 4110-01037-1 reveals it to be a moderately aged (~<5 Gyr) solar-like star having a mass of 1.07 +/- 0.08 MSun and radius of 0.99 +/- 0.18 RSun. We analyze 32 radial velocity measurements from the SDSS-III MARVELS survey as well as 6 supporting radial velocity measurements from the SARG spectrograph on the 3.6m TNG telescope obtained over a period of ~2 years. The best Keplerian orbital fit parameters were found to have a period of 78.994 +/- 0.012 days, an eccentricity of 0.1095 +/- 0.0023, and a semi-amplitude of 4199 +/- 11 m/s. We determine the minimum companion mass (if sin i = 1) to be 97.7 +/- 5.8 MJup. The system's companion to host star mass ratio, >0.087 +/- 0.003, places it at the lowest end of observed values for short period stellar companions to solar-like (Teff ~< 6000 K) stars. One possible way to create such a system would be if a triple-component stellar multiple broke up into a short period, low q binary during the cluster dispersal phase of its lifetime. A candidate tertiary body has been identified in the system via single-epoch, high contrast imagery. If this object is confirmed to be co-moving, we estimate it would be a dM4 star. We present these results in the context of our larger-scale effort to constrain the statistics of low mass stellar and brown dwarf companions to FGK-type stars via the MARVELS survey.Comment: 22 pages; accepted in A

    MARVELS-1: A face-on double-lined binary star masquerading as a resonant planetary system; and consideration of rare false positives in radial velocity planet searches

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    We have analyzed new and previously published radial velocity observations of MARVELS-1, known to have an ostensibly substellar companion in a ~6- day orbit. We find significant (~100 m/s) residuals to the best-fit model for the companion, and these residuals are naively consistent with an interior giant planet with a P = 1.965d in a nearly perfect 3:1 period commensuribility (|Pb/Pc - 3| < 10^{-4}). We have performed several tests for the reality of such a companion, including a dynamical analysis, a search for photometric variability, and a hunt for contaminating stellar spectra. We find many reasons to be critical of a planetary interpretation, including the fact that most of the three-body dynamical solutions are unstable. We find no evidence for transits, and no evidence of stellar photometric variability. We have discovered two apparent companions to MARVELS-1 with adaptive optics imaging at Keck; both are M dwarfs, one is likely bound, and the other is likely a foreground object. We explore false-alarm scenarios inspired by various curiosities in the data. Ultimately, a line profile and bisector analysis lead us to conclude that the ~100 m/s residuals are an artifact of spectral contamination from a stellar companion contributing ~15-30% of the optical light in the system. We conclude that origin of this contamination is the previously detected radial velocity companion to MARVELS-1, which is not, as previously reported, a brown dwarf, but in fact a G dwarf in a face-on orbit.Comment: ApJ 770, 119. 24 pp emulate ApJ style, 12 figures (One is very large). v2: corrects two (important!) errors: A priori chance of this alignment or worse is 0.1% (not 0.01%) and the primary has THREE total companions (not four

    Hundreds of variants clustered in genomic loci and biological pathways affect human height

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    Most common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits, but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait. The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P < 0.001). Second, the likely causal gene is often located near the most strongly associated variant: in 13 of 21 loci containing a known skeletal growth gene, that gene was closest to the associated variant. Third, at least 19 loci have multiple independently associated variants, suggesting that allelic heterogeneity is a frequent feature of polygenic traits, that comprehensive explorations of already-discovered loci should discover additional variants and that an appreciable fraction of associated loci may have been identified. Fourth, associated variants are enriched for likely functional effects on genes, being over-represented among variants that alter amino-acid structure of proteins and expression levels of nearby genes. Our data explain approximately 10% of the phenotypic variation in height, and we estimate that unidentified common variants of similar effect sizes would increase this figure to approximately 16% of phenotypic variation (approximately 20% of heritable variation). Although additional approaches are needed to dissect the genetic architecture of polygenic human traits fully, our findings indicate that GWA studies can identify large numbers of loci that implicate biologically relevant genes and pathways.
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