794 research outputs found

    Household's Preferences and Monetary Policy Inertia

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    The estimation of monetary policy rules suggests that the interest rates set by central banks move with a certain inertia. Although a number of hypotheses have been suggested to explain this phenomenon, its ultimate origin is unclear, thus delineating this issue as a modern "puzzle" in monetary economics. We show that household's preferences can play an important role in determining optimal interest rate inertia. Importantly, this can occur even when the central bank has egligible preferences for smoothing the interest rate

    Saccades influence the visibility of targets in rapid stimulus sequences: the roles of mislocalization, retinal distance and remapping

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    Briefly presented targets around the time of a saccade are mislocalized towards the saccadic landing point. This has been taken as evidence for a remapping mechanism that accompanies each eye movement, helping maintain visual stability across large retinal shifts. Previous studies have shown that spatial mislocalization is greatly diminished when trains of brief stimuli are presented at a high frequency rate, which might help to explain why mislocalization is rarely perceived in everyday viewing. Studies in the laboratory have shown that mislocalization can reduce metacontrast masking by causing target stimuli in a masking sequence to be perceived as shifted in space towards the saccadic target and thus more easily discriminated. We investigated the influence of saccades on target discrimination when target and masks were presented in a rapid serial visual presentation (RSVP), as well as with forward masking and with backward masking. In a series of experiments, we found that performance was influenced by the retinal displacement caused by the saccade itself but that an additional component of un-masking occurred even when the retinal location of target and mask was matched. These results speak in favor of a remapping mechanism that begins before the eyes start moving and continues well beyond saccadic termination

    Pre-saccadic perception: separate time courses for enhancement and spatial pooling at the saccade target

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    We interact with complex scenes using eye movements to select targets of interest. Studies have shown that the future target of a saccadic eye movement is processed differently by the visual system. A number of effects have been reported, including a benefit for perceptual performance at the target (“enhancement”), reduced influences of backward masking (“unmasking”), reduced crowding (“un-crowding”) and spatial compression towards the saccade target. We investigated the time course of these effects by measuring orientation discrimination for targets that were spatially crowded or temporally masked. In four experiments, we varied the target-flanker distance, the presence of forward/backward masks, the orientation of the flankers and whether participants made a saccade. Masking and randomizing flanker orientation reduced performance in both fixation and saccade trials. We found a small improvement in performance on saccade trials, compared to fixation trials, with a time course that was consistent with a general enhancement at the saccade target. In addition, a decrement in performance (reporting the average flanker orientation, rather than the target) was found in the time bins nearest saccade onset when random oriented flankers were used, consistent with spatial pooling around the saccade target. We did not find strong evidence for un-crowding. Overall, our pattern of results was consistent with both an early, general enhancement at the saccade target and a later, peri-saccadic compression/pooling towards the saccade target

    Fooling the eyes: the influence of a sound-induced visual motion illusion on eye movements

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    The question of whether perceptual illusions influence eye movements is critical for the long-standing debate regarding the separation between action and perception. To test the role of auditory context on a visual illusion and on eye movements, we took advantage of the fact that the presence of an auditory cue can successfully modulate illusory motion perception of an otherwise static flickering object (sound-induced visual motion effect). We found that illusory motion perception modulated by an auditory context consistently affected saccadic eye movements. Specifically, the landing positions of saccades performed towards flickering static bars in the periphery were biased in the direction of illusory motion. Moreover, the magnitude of this bias was strongly correlated with the effect size of the perceptual illusion. These results show that both an audio-visual and a purely visual illusion can significantly affect visuo-motor behavior. Our findings are consistent with arguments for a tight link between perception and action in localization tasks

    Braincase of Limnoscelis paludis Williston

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    Limnoscelis paludis historically has been considered close to the ancestry of reptiles. Although the unique holotype skeleton is largely complete, its braincase has never been adequately described. Recent mechanical preparation has exposed the braincase laterally, dorsally, and in cross section for the first time, and has enhanced the preexisting ventral and occipital views, Newly revealed attributes include a fused basiparasphenoid, a fused otic, a feebly ossified zone separating anterior and posterior braincase divisions, paired basiparasphenoid ossifications of the dorsum sellae, a sphenethmoid with Y-shaped transverse cross section, an ossified synotic, a concave occipital condyle, reduced exoccipitals, and the absence of posttemporal fenestrae. Cladistic analysis of many cranial characters, including those of the braincase, indicates that among Paleozoic tetrapods, Limnoscelis is most closely related to the diadectomorphs Tseajaia and Diadectes. The diadectomorphs are primitive reptiles, most closely related to the pelycosaurs

    Fat embolism after intraosseous catheters in pediatric forensic autopsies.

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    In our center, we performed the autopsy of a child who died from drowning and presented, at autopsy, a major pulmonary fat embolism (PFE). A cardiopulmonary resuscitation (CPR) was performed, including infusion by intraosseous catheter (IIC). No other traumatic lesions and diseases classically related to a risk of PFE were detected. According to some animal studies, we considered the IIC as the only possible cause for PFE. However, we could not find literature to confirm this hypothesis in humans, especially in a pediatric population. To verify the occurrence of PFE after IIC in a pediatric population, we retrospectively selected 20 cases of pediatric deaths autopsied in our center, in which a CPR was performed, without bone fractures or other possible causes of PFE: 13 cases with IIC (group A) and 7 cases without IIC (group B). Several exclusion criteria were considered. The histology slides of the pulmonary tissue were stained by Oil Red O. PFE was classified according to the Falzi scoring system. In group A, 8 cases showed PFE: 4 cases with a score 1 of Falzi and 4 cases with a score 2 of Falzi. In group B, no case showed PFE. The difference between the two groups was statistically significant. The results of our study seem to confirm that IIC can lead to PFE in a pediatric population and show that the PFE after IIC can be important (up to score 2 of Falzi). To the best of our knowledge, our study is the first specifically focused on the occurrence of PFE after IIC in a pediatric population by using autoptic data

    Can Euroscepticism Contribute to a European Public Sphere? The Europeanization of Media Discourses about Euroscepticism across Six Countries

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    This study compares the media discourses about Euroscepticism in 2014 across six countries (United Kingdom, Ireland, France, Spain, Sweden, and Denmark). We assess the extent to which the mass media's reporting of Euroscepticism indicates the Europeanization of public spheres. Using a mixed-methods approach combining LDA topic modeling and qualitative coding, we find that approximately 70 per cent of print articles mentioning "Euroscepticism" or "Eurosceptic" are framed in a non-domestic (i.e. European) context. In five of the six cases studied, articles exhibiting a European context are strikingly similar in content, with the British case as the exception. However, coverage of British Euroscepticism drives Europeanization in other Member States. Bivariate logistic regressions further reveal three macro-level structural variables that significantly correlate with a Europeanized media discourse: newspaper type (tabloid or broadsheet), presence of a strong Eurosceptic party, and relationship to the EU budget (net contributor or receiver of EU funds).Comment: 29 pages, 2 figures, 4 tables, 2 appendice
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