References of "Vidal, F"
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See detailSPHERE+: Imaging young Jupiters down to the snowline
Boccaletti, A.; Chauvin, G.; Mouillet, D. et al

E-print/Working paper (2020)

SPHERE (Beuzit et al,. 2019) has now been in operation at the VLT for more than 5 years, demonstrating a high level of performance. SPHERE has produced outstanding results using a variety of operating ... [more ▼]

SPHERE (Beuzit et al,. 2019) has now been in operation at the VLT for more than 5 years, demonstrating a high level of performance. SPHERE has produced outstanding results using a variety of operating modes, primarily in the field of direct imaging of exoplanetary systems, focusing on exoplanets as point sources and circumstellar disks as extended objects. The achievements obtained thus far with SPHERE (~200 refereed publications) in different areas (exoplanets, disks, solar system, stellar physics...) have motivated a large consortium to propose an even more ambitious set of science cases, and its corresponding technical implementation in the form of an upgrade. The SPHERE+ project capitalizes on the expertise and lessons learned from SPHERE to push high contrast imaging performance to its limits on the VLT 8m-telescope. The scientific program of SPHERE+ described in this document will open a new and compelling scientific window for the upcoming decade in strong synergy with ground-based facilities (VLT/I, ELT, ALMA, and SKA) and space missions (Gaia, JWST, PLATO and WFIRST). While SPHERE has sampled the outer parts of planetary systems beyond a few tens of AU, SPHERE+ will dig into the inner regions around stars to reveal and characterize by mean of spectroscopy the giant planet population down to the snow line. Building on SPHERE's scientific heritage and resounding success, SPHERE+ will be a dedicated survey instrument which will strengthen the leadership of ESO and the European community in the very competitive field of direct imaging of exoplanetary systems. With enhanced capabilities, it will enable an even broader diversity of science cases including the study of the solar system, the birth and death of stars and the exploration of the inner regions of active galactic nuclei. [less ▲]

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See detailActivation of the supplementary motor area and of attentional networks during temporal processing
Macar, F.; Lejeune, Helga ULiege; Kirsch, Murielle ULiege et al

in Experimental Brain Research (2002), 142(4), 475-485

This paper first provides a survey of the expanding brain imaging literature in the field of time processing. showing that particular task features (discrete vs rhythmic, perceptual vs motor) do not ... [more ▼]

This paper first provides a survey of the expanding brain imaging literature in the field of time processing. showing that particular task features (discrete vs rhythmic, perceptual vs motor) do not significantly affect the basic pattern of activation observed. Next, positron emission tomography (PET) data obtained in a timing task (temporal reproduction) with two distinct duration ranges (2.2-3.2 and 9-13 s) are reported. The stimuli consisted of vibrations applied to the subject's right middle finger. When the vibration ended, the subject estimated an interval identical to its length before pressing a response button. The control task used cued responses with comparable intervals and stimuli, The pattern of activation obtained in the timing task as compared to control mainly included areas having attentional functions (the right dorsolateral prefrontal, inferior parietal, and anterior cingulate cortices), and the supplementary motor area (SMA). No significant difference was seen as a function of the duration range. It is argued, firstly. that involvement of the attentional areas derives from specific relations between attention and the temporal accumulator, as described by dominant timing models. and, secondly, that the SMA, or more probably one of its subregions, subserves time processing [less ▲]

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See detailEtude par spectroscopie de génération de la fréquence somme de l'interface méthanol-platine
Vidal, F.; Busson, B.; Six, C. et al

in J. Phys. IV France (2002), 12

La spectroscopie vibrationnelle non-linéaire par génération de la fréquence somme est une sonde particulièrement adaptée à l'étude des interfaces entre milieux denses. Cette technique a été appliquée à l ... [more ▼]

La spectroscopie vibrationnelle non-linéaire par génération de la fréquence somme est une sonde particulièrement adaptée à l'étude des interfaces entre milieux denses. Cette technique a été appliquée à l'étude de l'interface électrochimique monocristal de platine/solution acide de méthanol, système qui constitue un modèle de pile à combustible, dispositif où l'énergie chimique est directement convertie en énergie électrique. Les propriétés vibrationnelles dépendent fortement de l'orientation cristallographique de l'électrode de platine. [less ▲]

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See detailTransprocedural invariance of the neural networks involved in the estimation of duration : contribution of PET studies (poster abstract)
Lejeune, Helga ULiege; Maquet, Pierre ULiege; Kirsch, Murielle ULiege et al

in Besson, M. (Ed.) Neural substrates of cognitive functions : conference in homage to Jean Requin (1938-1996), Marseille, May 15-16, 1997 (1997)

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See detailBrain activation induced by estimation of duration : A PET study
Maquet, Pierre ULiege; Lejeune, Helga ULiege; Pouthas, V. et al

in NeuroImage (1996), 3(2), 119-126

Duration information about a visual stimulus requires processing as do other visual features such as size or intensity. Using positron emission tomography, iterative (H2O)-O-15 infusions, and statistical ... [more ▼]

Duration information about a visual stimulus requires processing as do other visual features such as size or intensity. Using positron emission tomography, iterative (H2O)-O-15 infusions, and statistical parametric mapping, we investigated the neural correlates of time processing. Nine normal subjects underwent six serial rCBF. Three tasks were studied: (a) Atemporal generalization task (D task) in which the subjects had to judge (by pressing one of two keys) whether the duration of the illumination of a green LED was equal to or different from that of a previously presented standard; (b) An intensity generalization task. (I task) in which the judgment concerned the intensity of the LED; and (c) A control task (C task) in which the subjects had to press one of the two keys at random in response to LED illumination. A significant increase in rCBF during the D task, compared to that during the C task, was observed in right prefontal cortex, right inferior parietal lobule, anterior cingulate cortex, vermis, and a region corresponding to the left fusiform gyrus. A significant increase in rCBF during the I task, compared to that during the C task, was observed in right prefontal cortex, right inferior parietal lobule, right extrastriate cortex, anterior cingulate cortex, left inferior parietal lobule, vermis, and two symmetrical regions corresponding to the fusiform gyri. No significant activation was observed in the D task when compared to that in the I task. We propose that these cortical maps are best explained by the recruitment of visual attention and memory structures, which play a major role in prospective time judgements as indicated by behavioral studies. The data also suggest that the temporal dimension of a visual stimulus is processed in attributes. the same areas as other visual attributes. [less ▲]

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See detailFrontal activation observed with PET in visual discrimination involving duration or intensity parameters
Maquet, Pierre ULiege; Lejeune, Helga ULiege; Pouthas, V. et al

in Proceedings of the sixth meeting of the European Neurological Society, Tutzing (Munich), RFA, June 17-21 (1995)

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