Fitness Training As a Body-Centered Hobby: the Serious Leisure Perspective for Explaining Exercise Practice

Physical exercise is an activity whose health-related benefits have been promoted by health professionals and social institutions. However, given that the levels of practice are not ideal, the subjective variables - that give meaning, provide continuity and may increase exercise adherence - need to be studied in depth. In this sense, fitness training is analyzed as a form of serious leisure, a body-centered hobby - a way to practice and relate to the activity that leads its practitioners to adhere more to it, orienting them towards a career in acquiring and expressing skills, knowledge and experience. In total, 1,134 people (588 men, 546 women) doing fitness training, aged between 18 and 70 years old (M = 34.7, SD = 13.06), answered a questionnaire about time dedicated to exercise as serious leisure and its derived and complementary benefits. Student's t Coefficient and ANOVA were used to show the significance of the differences among the scores obtained for the rewards related to exercise and the other variables of the study. The results highlight that exercise as serious leisure is an activity whose weekly time investment makes it to acquire a central role when rewarded by sense of accomplishment, contact with others, improved health and being outdoors with the family. To conclude, this study enhances that characterizing fitness training as a body-centered hobby - which shares the principles of serious leisure - implies a new approach to the analysis of exercise while also suggesting new ways of promoting it

Cosmic Shear of the Microwave Background: The Curl Diagnostic

Weak-lensing distortions of the cosmic-microwave-background (CMB) temperature and polarization patterns can reveal important clues to the intervening large-scale structure. The effect of lensing is to deflect the primary temperature and polarization signal to slightly different locations on the sky. Deflections due to density fluctuations, gradient-type for the gradient of the projected gravitational potential, give a direct measure of the mass distribution. Curl-type deflections can be induced by, for example, a primordial background of gravitational waves from inflation or by second-order effects related to lensing by density perturbations. Whereas gradient-type deflections are expected to dominate, we show that curl-type deflections can provide a useful test of systematics and serve to indicate the presence of confusing secondary and foreground non-Gaussian signals.Comment: 8 pages, 3 figures; PRD submitte

Los ocios serio y casual en la construcción de la identidad juvenil. Un estudio basado en la autoexpresión de los participantes

Leisure activities and identity interact and structure young people’s lives. Empirical research on such interaction is scarce and contradictory. This paper explores the relationships between leisure activities with different levels of commitment (serious, casual) and identity traits. A total of 938 young people (476 men and 462 women) aged 18 to 24 (M = 21.13; DT = 1.98) completed a time budget (TB) and a self-description questionnaire about identity based on the Twenty-Statements Test, as well an association between the TB and the self-descriptions. The study shows the complementarity of serious and casual leisure in the formation of youth identities and gender differences.Los ocios y la identidad interaccionan y vertebran la vida en la juventud. Las investigaciones empíricas sobre dicha interacción son escasas y contradictorias. Este trabajo estudia las relaciones entre ocios con diferentes implicaciones (serio, casual) y rasgos identitarios. 938 jóvenes (476 hombres y 462 mujeres) de entre 18 y 24 años (M= 21,13; DT = 1,98) respondieron: un Presupuesto de Tiempo (PT); un cuestionario de autodescripciones identitarias basadas en el Twenty-Statement Test (TST) y una prueba de asociación entre el PT y las auto-descripciones. Se muestra la complementariedad de ocios serios y casuales en la configuración de las identidades juveniles y diferencias de género.This study was funded by the Ministry of Economy and Competitiveness of Spain conjointly with the European Regional Development Fund (project EDU2012-39080-C07-04)

Weak Lensing with SDSS Commissioning Data: The Galaxy-Mass Correlation Function To 1/h Mpc

(abridged) We present measurements of galaxy-galaxy lensing from early commissioning imaging data from the Sloan Digital Sky Survey (SDSS). We measure a mean tangential shear around a stacked sample of foreground galaxies in three bandpasses out to angular radii of 600'', detecting the shear signal at very high statistical significance. The shear profile is well described by a power-law. A variety of rigorous tests demonstrate the reality of the gravitational lensing signal and confirm the uncertainty estimates. We interpret our results by modeling the mass distributions of the foreground galaxies as approximately isothermal spheres characterized by a velocity dispersion and a truncation radius. The velocity dispersion is constrained to be 150-190 km/s at 95% confidence (145-195 km/s including systematic uncertainties), consistent with previous determinations but with smaller error bars. Our detection of shear at large angular radii sets a 95% confidence lower limit $s>140^{\prime\prime}$, corresponding to a physical radius of $260h^{-1}$ kpc, implying that galaxy halos extend to very large radii. However, it is likely that this is being biased high by diffuse matter in the halos of groups and clusters. We also present a preliminary determination of the galaxy-mass correlation function finding a correlation length similar to the galaxy autocorrelation function and consistency with a low matter density universe with modest bias. The full SDSS will cover an area 44 times larger and provide spectroscopic redshifts for the foreground galaxies, making it possible to greatly improve the precision of these constraints, measure additional parameters such as halo shape, and measure the properties of dark matter halos separately for many different classes of galaxies.Comment: 28 pages, 11 figures, submitted to A

Topological Defects and Cosmology

Many particle physics models of matter admit solutions corresponding to stable or long-lived topological defects. In the context of standard cosmology it is then unavoidable that such defects will form during phase transitions in the very early Universe. Certain types of defects lead to disastrous consequences for cosmology, others may play a useful role, as possible seeds for the formation of structure in the Universe, or in mediating baryon number violating processes. In all cases, topological defects lead to a fruitful interplay between particle physics and cosmology.Comment: 17 pages, no figures; Invited lectures at WHEPP-5, IUCAA, Pune, India, Jan. 12 - 26 199

The Angular Correlation Function of Galaxies from Early SDSS Data

The Sloan Digital Sky Survey is one of the first multicolor photometric and spectroscopic surveys designed to measure the statistical properties of galaxies within the local Universe. In this Letter we present some of the initial results on the angular 2-point correlation function measured from the early SDSS galaxy data. The form of the correlation function, over the magnitude interval 18<r*<22, is shown to be consistent with results from existing wide-field, photographic-based surveys and narrower CCD galaxy surveys. On scales between 1 arcminute and 1 degree the correlation function is well described by a power-law with an exponent of ~ -0.7. The amplitude of the correlation function, within this angular interval, decreases with fainter magnitudes in good agreement with analyses from existing galaxy surveys. There is a characteristic break in the correlation function on scales of approximately 1-2 degrees. On small scales, < 1', the SDSS correlation function does not appear to be consistent with the power-law form fitted to the 1'< theta <0.5 deg data. With a data set that is less than 2% of the full SDSS survey area, we have obtained high precision measurements of the power-law angular correlation function on angular scales 1' < theta < 1 deg, which are robust to systematic uncertainties. Because of the limited area and the highly correlated nature of the error covariance matrix, these initial results do not yet provide a definitive characterization of departures from the power-law form at smaller and larger angles. In the near future, however, the area of the SDSS imaging survey will be sufficient to allow detailed analysis of the small and large scale regimes, measurements of higher-order correlations, and studies of angular clustering as a function of redshift and galaxy type

KL Estimation of the Power Spectrum Parameters from the Angular Distribution of Galaxies in Early SDSS Data

We present measurements of parameters of the 3-dimensional power spectrum of galaxy clustering from 222 square degrees of early imaging data in the Sloan Digital Sky Survey. The projected galaxy distribution on the sky is expanded over a set of Karhunen-Loeve eigenfunctions, which optimize the signal-to-noise ratio in our analysis. A maximum likelihood analysis is used to estimate parameters that set the shape and amplitude of the 3-dimensional power spectrum. Our best estimates are Gamma=0.188 +/- 0.04 and sigma_8L = 0.915 +/- 0.06 (statistical errors only), for a flat Universe with a cosmological constant. We demonstrate that our measurements contain signal from scales at or beyond the peak of the 3D power spectrum. We discuss how the results scale with systematic uncertainties, like the radial selection function. We find that the central values satisfy the analytically estimated scaling relation. We have also explored the effects of evolutionary corrections, various truncations of the KL basis, seeing, sample size and limiting magnitude. We find that the impact of most of these uncertainties stay within the 2-sigma uncertainties of our fiducial result.Comment: Fig 1 postscript problem correcte