The relationship between student behaviour patterns and teacher burnout.

A wide range of factors have been proposed as antecedents of burnout in teachers, including student behaviour in the classroom. Several studies have shown associations between student misbehaviour and teacher burnout. However, researchers have rarely incorporated a direct measure of teachers' perceptions of student behaviour in their own classroom. The main aims of the present study of 100 British primary school teachers were: (a) to explore the properties of a measure of student behaviour in the classroom (the Pupil Behaviour Patterns scale PBP; Friedman, 1995) and (b) to test the prediction of burnout dimensions from dimensions of student behaviour assessed by the PBP. An exploratory factor analysis confirmed the PBP domains of disrespectful behaviour, sociability and attentiveness. Furthermore, reliability analyses supported the internal consistency of the scales. Regression analysis of teacher burnout showed differential prediction by PBP sub-domains: disrespect predicted emotional exhaustion and depersonalization burnout, and lack of sociability predicted depersonalization and personal accomplishment burnout. Methodological problems are discussed along with suggestions for future theoretical and empirical development. In particular, we focus on the potential role of psychological variables such as teacher self-efficacy and coping strategies in explaining how teacher well-being is affected by student behaviour in the classroom. <br/

Lutein epoxide cycle, light harvesting and photoprotection in species of the tropical tree genus Inga

Dynamics and possible function of the lutein epoxide (Lx) cycle, that is, the reversible conversion of Lx to lutein (L) in the light-harvesting antennae, were investigated in leaves of tropical tree species. Photosynthetic pigments were quantified in nine Inga species and species from three other genera. In Inga, Lx levels were high in shade leaves (mostly above 20 mmol mol(-1) chlorophyll) and low in sun leaves. In Virola surinamensis, both sun and shade leaves exhibited very high Lx contents (about 60 mmol mol(-1) chlorophyll). In Inga marginata grown under high irradiance, Lx slowly accumulated within several days upon transfer to deep shade. When shade leaves of I. marginata were briefly exposed to the sunlight, both violaxanthin and Lx were quickly de-epoxidized. Subsequently, overnight recovery occurred only for violaxanthin, not for Lx. In such leaves, containing reduced levels of Lx and increased levels of L, chlorophyll fluorescence induction showed significantly slower reduction of the photosystem II electron acceptor, Q(A), and faster formation as well as a higher level of non-photochemical quenching. The results indicate that slow Lx accumulation in Inga leaves may improve light harvesting under limiting light, while quick de-epoxidation of Lx to L in response to excess light may enhance photoprotection