Sawfly Sex Pheromones: Analysis of Their Impact on Pine Odor Attractive to Egg Parasitoids.

Pinus sylvestris trees are known to efficiently defend themselves against eggs of the herbivorous sawfly Diprion pini. Their direct defense against eggs is primable by prior exposure to the sex pheromones of this species and their indirect defense involves attraction of egg parasitoids by egg-induced pine needle odor. But it is unknown whether exposure of pine to D.

Drought induces moderate, diverse changes in the odour of grassland species.

Plants react to drought stress with numerous changes including altered emissions of volatile organic compounds (VOC) from leaves, which provide protection against oxidative tissue damage and mediate numerous biotic interactions. Despite the share of grasslands in the terrestrial biosphere, their importance as carbon sinks and their contribution to global biodiversity, little is known about the influence of drought on VOC profiles of grassland species. Using coupled gas chromatography-mass spectrometry, we analysed the odorants emitted by 22 European grassland species exposed to an eight-week-lasting drought treatment (DT; 30% water holding capacity, WHC).

Reduction of Aversive Learning Rates in Pavlovian Conditioning by Angiotensin II Antagonist Losartan: A Randomized Controlled Trial.

Background: Angiotensin receptor blockade has been linked to aspects of aversive learning and memory formation and to the prevention of posttraumatic stress disorder symptom development.

Methods: We investigated the influence of the angiotensin receptor blocker losartan on aversive Pavlovian conditioning using a probabilistic learning paradigm. In a double-blind, randomized, placebo-controlled design, we tested 45 (18 female) healthy volunteers during a baseline session, after application of losartan or placebo (drug session), and during a follow-up session.

Trait anxiety is associated with hidden state inference during aversive reversal learning.

Updating beliefs in changing environments can be driven by gradually adapting expectations or by relying on inferred hidden states (i.e. contexts), and changes therein.