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The purpose of this paper is to present greenhouse gas study results for biofuels produced with partial qualified utilisation of pulp wood or forest residues when integrated into kraft pulp mill systems. The impact of considering biogenic carbon on the results is also presented.

The material and energy balances of the integrated ethanol production were simulated for the study with a mill‐wide simulation model. Data for the simulation were obtained from prehydrolysis and cooking experiments. The life cycle model for greenhouse gas calculation was created based on the simulation results. In this paper, the change of forest carbon stock caused by residue removal from forest soil and carbon delay of forest growth after stand felling were also taken into consideration, to discuss the true greenhouse gas emissions of forest biomass utilisation.

The emission reduction levels achieved with these ethanol fuels derived from forest biomass ranged from 80 to 90 per cent when biogenic carbon emissions were neglected.

The findings indicate that in both cases a significant percentage of the side flows containing energy can be utilised to produce excess electricity when the ethanol plant is integrated into the pulp mill. The findings also indicate that the carbon storage impact of forest biomasses affects significantly the emission values of both studied fuels and overturns the emission savings of prehydrolysed chip based ethanol.

The purpose of this paper is to assess the socioscientific issue (SSI) method as a way of improving seventh graders’ nutrition know-how on dietary supplements (DS), and to describe how students experience learning nutritional issues through the SSI method.

Participants were seventh graders from three different classes (n=43). Health education intervention lasted 7 h and it embodied the three-staged model: the scenario, the inquiry and the decision-making stages. The study was qualitative in nature. The data were collected through a questionnaire before and after the intervention. The data were analyzed using summative content analysis.

Intervention tended to deepen students’ know-how on vitamins and rational use of DS. Students’ experiences of learning nutritional issues through the SSI method were generally positive. The scenario stage was considered current and authentic. The inquiry stage and decision-making stage helped in understanding the societal connections between the study task and the rational use of DS.

SSI method enhances students’ knowledge about the rational use of DS. E-learning environment gave students possibilities to work collaboratively. Especially, possibilities to discuss with peers and share own experiences supported learning.

To solve the need of dietary supplements (DS) is a complex nutritional issue for society and for individuals. Since consumption of special diets has increased among adolescents, the rational consumption of DS is relevant and interesting learning topic at secondary school.