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The aim of the present work is to analyse differences between community children with normal weight vs community overweight children vs children with a clinical diagnose of obesity, at the level of the variables quality of life, psychological morbidity, self-concept and coping strategies. On this work were used the following questionnaires: Self-concept Scale for children and adolescents of Susan Harper, Depression Inventory (CDI), Anxiety Inventory (STAI), Quality of life Inventory (PedsQL), and Coping strategies Inventory (SCSI). The study sample has 267 children represented in three groups: group of community children with normal weight (N=147), group of community overweight children (N= 89) and a group of children with a clinical diagnosis of obesity (N= 31). The results from this study shown differences on quality of lif...
The surface morphology, structure and composition of human dentin treated with a femtosecond infrared laser (pulse duration 500 fs, wavelength 1030 nm, fluences ranging from 1 to 3 J cm(-2)) was studied by scanning electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The average dentin ablation threshold under these conditions was 0.6 +/- 0.2 J cm(-2) and the ablation rate achieved in the range 1 to 2 mu m/pulse for an average fluence of 3 J cm(-2). The ablation surfaces present an irregular and rugged appearance, with no significant traces of melting, deformation, cracking or carbonization. The smear layer was entirely removed by the laser treatment. For fluences only slightly higher than the ablation threshold the morphology of the laser-treated surfaces was very simila...
Presently, conditions ensuring the validity of bootstrap methods for the sample mean of (possibly heterogeneous) near epoch dependent (NED) functions of mixing processes are unknown. Here we establish the validity of the bootstrap in this context, extending the applicability of bootstrap methods to a class of processes broadly relevant for applications in economics and finance. Our results apply to two block bootstrap methods: the moving blocks bootstrap of K nsch (1989, Annals of Statistics 17, 1217 1241) and Liu and Singh (1992, in R. LePage L. Billiard (eds.), Exploring the Limits of the Bootstrap, 224 248) and the stationary bootstrap of Politis and Romano (1994a, Journal of the American Statistical Association 89, 1303 1313). In particular, the consistency of the bootstrap variance estimator for the sample mean is shown to be robu...
Comment: 9 pages, 6 figures, published in JSTAT
Comment: 7 pages, 6 figures. accepted for publication on PRE
Comment: 11 pages, 6 figures, to appear in J. Stat. Mech
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