Experiment 2 revealed that pDMS dopamine depletion did not compromise the acquisition of a conditional visual discrimination task in an operant box that required learning a rule of the type “”if the cue light is bright press left lever for reward, if dim press right lever”". Furthermore, experiment 3 showed that pDMS dopamine depletion did not impair the acquisition of a cross maze task that required learning a visual cue discrimination strategy to obtain food reward. Together results of experiments 2 and 3 indicate that dopamine signaling in the pDMS does not subserve stimulus
discrimination per se and stimulus-response learning.”
“Vanadium dioxide is investigated as potential oxide barrier in spin switches, and in order to incorporate VO(2) layers in complex multilayer devices, it is necessary to understand the relation selective HDAC inhibitors between bulk and surface/interface properties. Highly oriented VO(2) thin films were grown on (0001) sapphire single crystal substrates with reactive bias target ion beam deposition. CX-6258 in vitro In the analysis of the VO(2) films, bulk-sensitive
methods [x-ray diffraction (XRD) and transport measurements] and surface sensitive techniques [photoelectron spectroscopy (PES) and scanning tunneling microscopy and spectroscopy] were employed. The samples were subjected to heating cycles with annealing temperatures of up to 425 and 525 K. Prior to annealing the VO(2) films exhibit the transition from the monoclinic to the tetragonal phase with the concurrent change in conductivity
by more than a factor of 10(3) and their phase purity is confirmed by XRD. Annealing to 425 K and thus cycling across the metal-insulator transition (MIT) temperature has no impact on the bulk properties of the VO(2) film but the surface undergoes irreversible electronic changes. The observation of the valence band with PES during the annealing illustrates that the surface adopts a partially metallic character, which is retained after cooling. Annealing to a higher temperature (525 K) triggers a modification of the bulk, which MLN8237 inhibitor is evidenced by a considerable reduction in the MIT characteristics, and a degradation in crystallite morphology. The local measurement of the conductivity with scanning tunneling spectroscopy shows the transition of the surface from predominantly semiconducting surface prior to annealing to a surface with an overwhelming contribution from metallic sections afterward. The spatial distribution of metallic regions cannot be linked in a unique manner to the crystallite size or location within the crystallites. The onset of oxygen depletion at the surface is held responsible for this behavior. The onset of bulk modification at higher temperatures is most likely linked to oxygen loss and effusion along the grain boundaries and concurrent onset of sintering.