Optical/IR images of transition disks (TDs) have revealed deep intensity decrements in the rings of HAeBes HD 142527 and HD 100453, that can be interpreted as shadowing from sharply tilted inner disks, such that the outer disks are directly exposed to stellar light. Here we report similar dips in SPHERE+IRDIS differential polarized imaging (DPI) of TTauri DoAr 44. With a fairly axially symmetric ring in the sub mm radio continuum, DoAr 44 is likely also a warped system. We constrain the warp geometry by comparing radiative transfer predictions with the DPI data in H band (Q φ (H)) and with a re-processing of archival 336 GHz ALMA observations. The observed DPI shadows have coincident radio counterparts, but the intensity drops are much deeper in Q φ (H) (∼88%), compared to the shallow drops at 336 GHz (∼24%). Radiative transfer predictions with an inner disk tilt of ∼ 30 ± 5 deg approximately account for the observations. ALMA long-baseline observations should allow the observation of the warped gas kinematics inside the cavity of DoAr 44.

Sleep supports the consolidation of memory, and it has been proposed that this enhancing effect of sleep pertains in particular to memories which are encoded under control of prefrontal–hippocampal circuitry into an episodic memory system. Furthermore, repeated reactivation and transformation of such memories during sleep are thought to promote the de-contextualization of these memories. Here, we aimed to establish a behavioral model for the study of such sleep-dependent system consolidation in rats, using a go/nogo conditional discrimination learning task known to essentially depend on prefrontal–hippocampal function. Different groups of rats were trained to criterion on this task and, then, subjected to 80-min retention intervals filled with spontaneous morning sleep, sleep deprivation, or spontaneous evening wakefulness. In a subsequent test phase, the speed of relearning of the discrimination task was examined as indicator of memory, whereby rats were either tested in the same context as during training or in a different context. Sleep promoted relearning of the conditional discrimination task, and this effect was similar for testing memory in the same or different context (p < 0.001). Independent of sleep and wakefulness during the retention interval, animals showed faster relearning when tested in the same context as during learning, compared with testing in a different context (p < 0.001). The benefitting effect of sleep on discrimination learning was primarily due to an enhancing effect on response suppression during the nogo stimulus. We infer from these results that sleep enhances memory for inhibitory behavioral control in a generalized context-independent manner and thereby might eventually also contribute to the abstraction of schema-like representations.

En 2 experimentos se investigó el rol de las claves de extinción (CE), y estímulos asociados a estas, en la readquisición de la tolerancia condicionada al etanol. La ataxia causada por el etanol fue medida en 80 ratas, utilizando planos de deslizamiento en un procedimiento de 5 fases. El primer experimento (que utilizó 4 contextos y 40 ratas) mostró que la presentación del contexto de extinción por sí solo disminuyó la efectividad de la CE para reducir la readquisición de respuesta. El segundo experimento (hecho en un solo contexto, con 40 ratas y con la diferencia de que se usaron 2 estímulos que fueron pareados para algunos sujetos o explícitamente no pareados para otros) mostró que una clave secundaria puede reducir la readquisición, independientemente de si fue pareada con la CE o no. Los resultados de análisis de varianza mixtos y factoriales sugieren que la CE afectaría la recuperación de la respuesta a través de una asociación con el contexto de extinción; sin embargo, una clave de segundo orden, asociada a la CE, no lograría activar dicha asociación. Palabras clave: extinción, condicionamiento clásico, tolerancia a las drogas, etanol, ataxia Two experiments analyzed the role of extinction cues (EC) and stimuli associated to them in the reacquisition of conditioned ethanol tolerance. Ethanol-induced ataxia was measured in 80 rat subjects using a tilting plane, in a 5-phase procedure. The first experiment (which used 4 contexts and 40 rats) showed that the presentation of the extinction context by itself diminished the effectiveness of ECs in reducing response reacquisition. The second experiment (conducted in a single context with 40 rats and using 2 stimulus paired for some subjects or explicitly unpaired for others) showed that a secondary cue can reduce reacquisition, regardless of whether it was paired with the EC or not. The results of mixed and factor analyses of variance suggest that ECs affect response recovery through an association with the extinction context; however, a second-order cue associated to an EC appears to be unable to activate this association.

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