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Based on Inglehart's (1997) idea that the importance of modern values is challenged by a growing importance of postmodern values in postindustrialised societies, we analyse the consequences of students' attempts to integrate (modern) achievement values and (postmodern) well-being values. Since opportunities for value integration are limited, students should frequently experience conflicts, whether to work for school or to engage in free time activities. In a questionnaire study, students (n=184) showed mostly high scores in both, achievement and well-being values. Value conflict -measured by a specific conflict formula -was related to the frequency of action conflicts as well as to the reported difficulty to decide which action to pursue. Values predicted the students' school-related decisions. Furthermore, students with high achievement values reported better performance in schoolrelated tasks than students with high well-being values. Finally, values were systematically related to time investment and grades.

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Colletotrichum higginsianum is a hemibiotrophic ascomycete fungus that is adapted to Arabidopsis (Arabidopsis thaliana). After breaching the host surface, the fungus establishes an initial biotrophic phase in the penetrated epidermis cell, before necrotrophic growth is initiated upon further host colonization. We observed that partitioning of major leaf carbohydrates was shifted in favor of sucrose and at the expense of starch during necrotrophic fungal growth. Arabidopsis mutants with impaired starch turnover were more susceptible toward C. higginsianum infection, exhibiting a strong negative correlation between diurnal carbohydrate accumulation and fungal proliferation for the tested genotypes. By altering the length of the light phase and employing additional genotypes impaired in nocturnal carbon mobilization, we revealed that reduced availability of carbon enhances susceptibility in the investigated pathosystem. Systematic starvation experiments resulted in two important findings. First, we showed that carbohydrate supply by the host is dispensable during biotrophic growth of C. higginsianum, while carbon deficiency was most harmful to the host during the necrotrophic colonization phase. Compared with the wild type, the increases in the total salicylic acid pool and camalexin accumulation were reduced in starch-free mutants at late interaction stages, while an increased ratio of free to total salicylic acid did not convey elevated pathogenesis-related gene expression in starch-free mutants. These observations suggest that reduced carbon availability dampens induced defense responses. In contrast, starchfree mutants were more resistant toward the fungal biotroph Erysiphe cruciferarum, indicating that reduced carbohydrate availability influences susceptibility differently in the interaction with the investigated hemibiotrophic and biotrophic fungal pathogens.

Results from structural equation modelling supported the proposed model for the whole sample as well as for each school track. A planned course of the day can prevent procrastination and foster decisions for academic tasks in case of conflicts. Students' learning takes place within a societal context and reflects the values held in the respective culture.