It is generally claimed that glyphosate kills undesired plants by affecting the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme, disturbing the shikimate pathway. However, the mechanisms leading to plant death may also be related to secondary or indirect effects of glyphosate on plant physiology. Moreover, some plants can metabolize glyphosate to aminomethylphosphonic acid (AMPA) or be exposed to AMPA from different environmental matrices. AMPA is a recognized phytotoxin, and its co-occurrence with glyphosate could modify the effects of glyphosate on plant physiology. The present review provides an overall picture of alterations of plant physiology caused by environmental exposure to glyphosate and its metabolite AMPA, and summarizes their effects on several physiological processes. It particularly focuses on photosynthesis, from photochemical events to C assimilation and translocation, as well as oxidative stress. The effects of glyphosate and AMPA on several plant physiological processes have been linked, with the aim of better understanding their phytotoxicity and glyphosate herbicidal effects.

Our study shows that the occurrence of AR >or=2/4 is related to prosthesis/annulus discongruence even after adjustment for experience. Hence, to minimize paravalvular AR, appropriate annular measurements and prosthesis sizing are critical.

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French Ministry of Health.

The social organization of captive groups of adult male and female starlings caught in different localities was studied to understand the possible social basis of song sharing. In the nonbreeding season, the social organization was based on within-sex groups or pairs and a few intersexual pairs. The pattern of song sharing clearly reflected the social organization. Members of the social pairs of females shared most of their songs, whereas males shared songs with other males to an extent that depended on their degree of social association. Song sharing was mostly restricted to birds of the same sex. The ability for adult vocal plasticity in both males and females may reflect the variety of possible social situations in this species.In the past decade, the importance of social input on the amount and plasticity of song learning and the choice of tutor has been increasingly demonstrated in different species (indigo buntings [Passerina cyanea], Payne, 1981; marsh wrens [Cistothorus palustris], Kroodsma & Pickert, 1984; white-crowned sparrows [Zonotrichia leucophrys],