The use of crocetin in experimental atherosclerosis

Résumé L'action préventive de la crocetine de l'apparition de l'artério-sclerose sur l'aorte du lapin soumis à un régime hypercholestérolémiant est démontrée. Par contre le mécanisme d'action de cette substance n'est pas élucidé par les expériences relatées.     

A synthetic cyclol tripeptide

Zusammenfassung Das dem-Methylalanyl--methylalanyl--methylalanin entsprechende Oxazolon (III) isomerisiert leicht zum kristallisierten Cyclol (IV), dessen Struktur sich aus dem Übergang in das Imidazolon (V) unter Wasserabspaltung ergibt.     

Strong present-day aerosol cooling implies a hot future

Atmospheric aerosols counteract the warming effects of anthropogenic greenhouse gases by an uncertain, but potentially large, amount. This in turn leads to large uncertainties in the sensitivity of climate to human perturbations, and therefore also in carbon cycle feedbacks and projections of climate change. In the future, aerosol cooling is expected to decline relative to greenhouse gas forcing, because of the aerosols' much shorter lifetime and the pursuit of a cleaner atmosphere. Strong aerosol cooling in the past and present would then imply that future global warming may proceed at or even above the upper extreme of the range projected by the Intergovernmental Panel on Climate Change.     

Mate fidelity and intra-lineage polygyny in greater horseshoe bats

Mating strategies that lead to increased kinship within socially cooperative groups may offer inclusive fitness benefits to individuals, but can also result in higher levels of inbreeding. Here we show in a sexually segregated bat species that females avoid this conflict through two mating behaviours. First, most females revisit and breed with specific, individual males across years, so that their single offspring born in different years are full siblings. Second, relatives in the maternal line, including mothers and daughters, share breeding partners (intra-lineage polygyny) more often than expected by chance. Although these behaviours increased levels of co-ancestry among colony members, there was no concomitant rise in inbreeding. We suggest that when females engage in mate fidelity and intra-lineage polygyny, kin ties among female roost mates will be strengthened, thereby potentially contributing to social group cohesiveness. Our findings reveal the hidden complexity that can underlie polygynous breeding, and highlight a new potential route by which female mate choice could influence social evolution.