133 research outputs found

    The rotational shear layer inside the early red-giant star KIC 4448777

    Get PDF
    We present the asteroseismic study of the early red-giant star KIC 4448777, complementing and integrating a previous work (Di Mauro et al. 2016), aimed at characterizing the dynamics of its interior by analyzing the overall set of data collected by the {\it Kepler} satellite during the four years of its first nominal mission. We adopted the Bayesian inference code DIAMOND (Corsaro \& De Ridder 2014) for the peak bagging analysis and asteroseismic splitting inversion methods to derive the internal rotational profile of the star. The detection of new splittings of mixed modes, more concentrated in the very inner part of the helium core, allowed us to reconstruct the angular velocity profile deeper into the interior of the star and to disentangle the details better than in Paper I: the helium core rotates almost rigidly about 6 times faster than the convective envelope, while part of the hydrogen shell seems to rotate at a constant velocity about 1.15 times lower than the He core. In particular, we studied the internal shear layer between the fast-rotating radiative interior and the slow convective zone and we found that it lies partially inside the hydrogen shell above r0.05Rr \simeq 0.05R and extends across the core-envelope boundary. Finally, we theoretically explored the possibility for the future to sound the convective envelope in the red-giant stars and we concluded that the inversion of a set of splittings with only low-harmonic degree l3l\leq 3, even supposing a very large number of modes, will not allow to resolve the rotational profile of this region in detail.Comment: accepted for publication on Ap

    Influência do período de fermentação sobre a germinação de sementes do maracujá do mato.

    Get PDF
    O presente trabalho teve como objetivo avaliar o efeito do período de fermentação sobre a germinação de Passiflora cincinata Mast.Suplemento 1. Edição dos Resumos do 43 Congresso Brasileiro de Olericultura, Recife, 2003

    Health promotion interventions for community-dwelling older people with mild or pre-frailty : a systematic review and meta-analysis

    Get PDF
    BACKGROUND: Mild or pre-frailty is common and associated with increased risks of hospitalisation, functional decline, moves to long-term care, and death. Little is known about the effectiveness of health promotion in reducing these risks. This systematic review aimed to synthesise randomised controlled trials (RCTs) evaluating home and community-based health promotion interventions for older people with mild/pre-frailty. METHODS: We searched 20 bibliographic databases and 3 trials registers (January 1990 - May 2016) using mild/pre-frailty and associated terms. We included randomised controlled and crossover trials of health promotion interventions for community-dwelling older people (65+ years) with mild/pre-frailty and excluded studies focussing on populations in hospital, long term care facilities or with a specific condition. Risk of bias was assessed by two reviewers using the Cochrane Risk of Bias tool. We pooled study results using standardised mean differences (SMD) where possible and used narrative synthesis where insufficient outcome data were available. RESULTS: We included 10 articles reporting on seven trials (total n = 506 participants) and included five trials in a meta-analysis. Studies were predominantly small, of limited quality and six studies tested group exercise alone. One study additionally investigated a nutrition and exercise intervention and one evaluated telemonitoring. Interventions of exercise in groups showed mixed effects on functioning (no effects on self-reported functioning SMD 0.19 (95% CI -0.57 to 0.95) n = 3 studies; positive effects on performance-based functioning SMD 0.37 (95% CI 0.07 to 0.68) n = 3 studies). No studies assessed moves to long-term care or hospitalisations. CONCLUSIONS: Currently the evidence base is of insufficient size, quality and breadth to recommend specific health promotion interventions for older people with mild or pre- frailty. High quality studies of rigorously developed interventions are needed
    corecore