0000000001004184

AUTHOR

Jenni Karvonen

Thermal properties in low dimensional structures below 1 K

In this thesis thermal properties of low dimensional structures were experimentally studied at low temperatures with the help of tunnel junction thermometry and the Joule heating technique. The main objects of study were electron-phonon coupling in disordered thin metal films and phonon transport in suspended silicon nitride membranes. Our aim has been to clarify the effect of the phonon dimensionality, i.e. the effect of boundaries to the phonon modes and the transition from 3D to 2D phonons. The dimensionality cross over had not been observed before this work even though it is fabricationally a standard procedure to create the low dimensional environments for nanoscale applications and de…

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Associations of temperament and personality traits with frequency of physical activity in adulthood

Temperament and physical activity (PA) have been examined in children and adolescents, but little is known about these associations in adulthood. Personality traits, however, are known to contribute to PA in adults. This study, which examined both temperament and personality characteristics at age 42 in relation to frequency of PA at age 50 (JYLS, n = 214-261), also found associations with temperament traits. Positive associations were found between Orienting sensitivity and overall PA and between Extraversion and vigorous PA among women and between low Negative affectivity and overall and vigorous PA among men. Furthermore, Orienting sensitivity and Agreeableness were associated with vigor…

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Pathways from childhood socioemotional characteristics and cognitive skills to midlife health behaviours.

Objective: This longitudinal study investigated the pathways from childhood socioemotional characteristics and cognitive skills to health behaviours in midlife. Methods: Participants in the Jyväskylä Longitudinal Study of Personality and Social Development (JYLS) were followed from age 8 (n=369) to age 50 (n=271). Outcomes included physical activity, smoking, alcohol consumption and body mass index (BMI) assessed at ages 36, 42 and 50. Predictors were socioemotional characteristics (behavioural activity, negative emotionality, and well-controlled behaviour) and parents’ occupational status collected at age 8, cognitive skills (school success at age 14 and the highest education at age 27) an…

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