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  • Sennikov, Alexander Nikolaevich (INTERNATIONAL ASSOCIATION FOR PLANT TAXONOMY, 2015)
  • Kaartinen, Aija (Nordic Centre for Welfare and Social Issues, 2009)
  • Cantiello, Matteo; Braithwaite, Jonathan; Brandenburg, Axel; Del Sordo, Fabio; Käpylä, Petri; Langer, Norbert (2011)
    During their main sequence evolution, massive stars can develop convective regions very close to their surface. These regions are caused by an opacity peak associated with iron ionization. Cantiello et al. (2009) found a possible connection between the presence of sub-photospheric convective motions and small scale stochastic velocities in the photosphere of early-type stars. This supports a physical mechanism where microturbulence is caused by waves that are triggered by subsurface convection zones. They further suggest that clumping in the inner parts of the winds of OB stars could be related to subsurface convection, and that the convective layers may also be responsible for stochastic excitation of non-radial pulsations. Furthermore, magnetic fields produced in the iron convection zone could appear at the surface of such massive stars. Therefore subsurface convection could be responsible for the occurrence of observable phenomena such as line profile variability and discrete absorption components. These phenomena have been observed for decades, but still evade a clear theoretical explanation. Here we present preliminary results from 3D MHD simulations of such subsurface convection.
  • Lindén, Greger (University of Helsinki, Department of Communication, 1998)
    Lecture notes
  • Lindén, Greger (University of Helsinki, Department of Computer Science, 2001)
  • Tuohilampi, Laura; Hannula, Markku S.; Varas, Leonor (Suomen ainedidaktinen tutkimusseura ry, 2013)
    In the field of mathematics-related affect research, not many comparisons have been done with regard to Western-Latin countries. This article reports the state of 9-year old pupils’ self-related affect with respect to mathematics in two countries, i.e. Finland and Chile. Self-efficacy, mastery goal orientation, effort, and enjoyment of mathematics were under consideration. Through quantitative analysis, it was found that all the factors examined are highly positive in both countries. However, a small difference with regard to beliefs of self-efficacy and effort was found between the countries, in favour to Finland. Yet, young pupils’ self-related mathematical beliefs build up an optimistic view with respect to mathematics learning, and efforts should be made to maintain the situation similar during the following school years.
  • Untitled 
    Unknown author (2012)