Correlation of structural and spectroscopic properties of a photosynthetic reaction center

Polarized spectra of absorption and light-induced absorbance changes are presented for the crystallized reaction centers of Rhodopseudomonas viridis. We find that a model based on extended dipole interaction between all six pigments is capable of interpreting detailed features such as the contributions from the individual pigments to the various absorption peaks. Even though the pigments are arranged in approximate C2 symmetry, the optical spectra together with the calculations reflect deviations from this symmetry, which may be important in understanding the electron pathway

Emotions and motivation in mathematics education: theoretical considerations and empirical contributions

Emotions and motivation are important prereq-uisites, mediators, and outcomes of learning and achieve-ment. In this article, we first review major theoretical approaches and empirical findings in research on students\u27 emotions and motivation in mathematics, including a dis-cussion of how classroom instruction can support emo-tions and motivation. Based on this review, we encourage researchers from mathematics education and other dis-ciplines of educational research to combine their efforts. Second, we provide an overview of the contributions in this special issue, most of which reflect such a combination of efforts by considering perspectives from both mathematics education and other fields of educational research. Finally, we consider the neglect of intervention studies and outline directions for future research. We identify intervention studies that target emotions and motivation as one promis-ing but so far underrepresented line of research in mathe-matics education and review results from existing interven-tion studies. For future research, we suggest that researchers should implement fine-grained concepts, assessment instru-ments, theoretical hypotheses, and methods of analysis tai-lored to the specific features of the mathematical domain to adequately investigate students\u27 emotions and motivation in this domain