Motion direction and luminance contrast are two central features in the representation of visual motion in humans. In five psychophysical experiments, we showed that these two features affect the ...perceived speed of a visual stimulus. Our data showed a surprising interaction between contrast and direction. Participants perceived downward moving stimuli as faster than upward or rightward stimuli, but only at high contrast. Likewise, luminance contrast produced an underestimation of motion speed, but mostly when the stimuli moved downward. We explained these novel phenomena by means of a theoretical model, accounting for prior knowledge of motion dynamics.
Several studies in the affective haptics research field showed the potential of using haptic technology to convey emotions in remote communications. In this context, it is of interest to simplify the ...haptic feedback without altering the informative content of the stimulus, with a two-fold advantage. On one side, it would allow the development of affective haptic devices whose technological complexity is limited, hence more compatible with wearability and portability requirements. On the other side, having a simplified set of stimuli would decrease the amount of data to be transmitted, thus improving the overall quality of remote haptic interactions. In this work, we investigated the correlation between the parameters regulating a caress-like stimulation and the perceived pleasantness. This was done by means of two experiments, in which we asked subjects to adjust the temperature and the motion velocity of a set of stimuli in order to find the most pleasant combination. Results indicated that subjects preferred different values of temperature and velocity of the stimulus depending on the proposed tactile stimulation. A small difference in the pleasantness ratings was observed between caresses provided with linear movements and those given as discrete sequences of taps. In particular, participants preferred linear movements set at <inline-formula><tex-math notation="LaTeX">34.5 \,^{\circ }\mathrm{C}</tex-math></inline-formula> and <inline-formula><tex-math notation="LaTeX">3.4 \,\mathrm{c}\mathrm{m}\mathrm{s}^{-1}</tex-math></inline-formula>. As regards caress-like stimuli provided with discrete sequences of taps, the preferred temperature and velocity were <inline-formula><tex-math notation="LaTeX">33.2 \,\mathrm{^{\circ }C}</tex-math></inline-formula> and <inline-formula><tex-math notation="LaTeX">2.9 \,\mathrm{c}\mathrm{m}\mathrm{s}^{-1}</tex-math></inline-formula>, respectively. The presence of vibration had a little effect on the perceived pleasantness.
During a smooth pursuit eye movement of a target stimulus, a briefly flashed stationary background appears to move in the opposite direction as the eye's motion
an effect known as the Filehne ...illusion. Similar illusions occur in audition, in the vestibular system, and in touch. Recently, we found that the movement of a surface perceived from tactile slip was biased if this surface was sensed with the moving hand. The analogy between these two illusions suggests similar mechanisms of motion processing between the vision and touch. In the present study, we further assessed the interplay between these two sensory channels by investigating a novel paradigm that associated an eye pursuit of a visual target with a tactile motion over the skin of the fingertip. We showed that smooth pursuit eye movements can bias the perceived direction of motion in touch. Similarly to the classical report from the Filehne illusion in vision, a static tactile surface was perceived as moving rightward with a leftward eye pursuit movement, and vice versa. However, this time the direction of surface motion was perceived from touch. The biasing effects of eye pursuit on tactile motion were modulated by the reliability of the tactile and visual stimuli, consistently with a Bayesian model of motion perception. Overall, these results support a modality- and effector-independent process with common representations for motion perception.
The study showed that smooth pursuit eye movement produces a bias in tactile motion perception. This phenomenon is modulated by the reliability of the tactile estimate and by the presence of a visual background, in line with the predictions of the Bayesian framework of motion perception. Overall, these results support the hypothesis of shared representations for motion perception.
In vision, Augmented Reality (AR) allows the superposition of digital content on real-world visual information, relying on the well-established See-through paradigm. In the haptic domain, a putative ...Feel-through wearable device should allow to modify the tactile sensation without masking the actual cutaneous perception of the physical objects. To the best of our knowledge, a similar technology is still far to be effectively implemented. In this work, we present an approach that allows, for the first time, to modulate the perceived softness of real objects using a Feel-through wearable that uses a thin fabric as interaction surface. During the interaction with real objects, the device can modulate the growth of the contact area over the fingerpad without affecting the force experienced by the user, thus modulating the perceived softness. To this aim, the lifting mechanism of our system warps the fabric around the fingerpad in a way proportional to the force exerted on the specimen under exploration. At the same time, the stretching state of the fabric is controlled to keep a loose contact with the fingerpad. We demonstrated that different softness perceptions for the same specimens can be elicited, by suitably controlling the lifting mechanism of the system.
Background and aims
Epidemiology of hepatocellular carcinoma (HCC) is changing in most areas of the world. This study aimed at updating the changing scenario of aetiology, clinical presentation, ...management and prognosis of HCC in Italy during the last 15 years.
Methods
Retrospective analysis of the Italian Liver Cancer (ITA.LI.CA) database included 6034 HCC patients managed in 23 centres from 2004 to 2018. Patients were divided into three groups according to the date of cancer diagnosis (2004‐2008, 2009‐2013 and 2014‐2018).
Results
The main results were: (i) a progressive patient ageing; (ii) a progressive increase of non‐viral cases and, particularly, of ‘metabolic’ and ‘metabolic + alcohol’ HCCs; (iii) a slightly decline of cases diagnosed under surveillance, but with an incremental use of the semiannual schedule; (iv) a favourable cancer stage migration; (v) an increased use of radiofrequency ablation to the detriment of percutaneous ethanol injection; (vi) improved outcomes of ablative and transarterial treatments; (vii) an improved overall survival (adjusted for the lead time in surveyed patients) in the last calendar period, particularly in viral patients; (viii) a large gap between the number of potential candidates (according to oncologic criteria and age) to liver transplant and that of transplanted patients.
Conclusions
During the last 15 years several aspects of HCC scenario have changed, as well as its management. The improvement in patient survival observed in the last period was likely because of a larger use of thermal ablation with respect to the less effective alcohol injection and to an improved management of intermediate stage patients.
In the perspective of fuelling the future generations of gas turbines by hydrogen rich syngas, the evaluation of the effect of a higher water vapour content into the flue gases on the TBC used, or ...potentially usable, is a need. For this purpose YPSZ APS TBC with two different microstructures have been exposed for 500 h at different temperatures in the range 1000 °C–1250 °C either in air and air +20% vol. H2O. The comparison between the different testing conditions has been performed in terms of sintering kinetics and phase stability, as evaluated by thermal diffusivity measurements and Synchrotron X-Rays diffraction, respectively. Furthermore the characterisation of thermal properties of two innovative TBCs (GZO-YPSZ and YAG) potentially able to withstand the CMAS attack and erosive environments, respectively, has been carried out.
No clear evidence of a different behaviour of TBC has been observed, at least in the considered aging time and temperature range.
To accurately time motor responses when intercepting falling balls we rely on an internal model of gravity. However, whether and how such a model is also used to estimate the spatial location of ...interception is still an open question. Here we addressed this issue by asking 25 participants to intercept balls projected from a fixed location 6 m in front of them and approaching along trajectories with different arrival locations, flight durations, and gravity accelerations (0
and 1
). The trajectories were displayed in an immersive virtual reality system with a wide field of view. Participants intercepted approaching balls with a racket, and they were free to choose the time and place of interception. We found that participants often achieved a better performance with 1
than 0
balls. Moreover, the interception points were distributed along the direction of a 1
path for both 1
and 0
balls. In the latter case, interceptions tended to cluster on the upper half of the racket, indicating that participants aimed at a lower position than the actual 0
path. These results suggest that an internal model of gravity was probably used in predicting the interception locations. However, we found that the difference in performance between 1
and 0
balls was modulated by flight duration, the difference being larger for faster balls. In addition, the number of peaks in the hand speed profiles increased with flight duration, suggesting that visual information was used to adjust the motor response, correcting the prediction to some extent.
Here we show that an internal model of gravity plays a key role in predicting where to intercept a fast-moving target. Participants also assumed an accelerated motion when intercepting balls approaching in a virtual environment at constant velocity. We also show that the role of visual information in guiding interceptive movement increases when more time is available.
Prognostic assessment in patients with hepatocellular carcinoma (HCC) remains controversial. Using the Italian Liver Cancer (ITA.LI.CA) database as a training set, we sought to develop and validate a ...new prognostic system for patients with HCC.
Prospective collected databases from Italy (training cohort, n = 3,628; internal validation cohort, n = 1,555) and Taiwan (external validation cohort, n = 2,651) were used to develop the ITA.LI.CA prognostic system. We first defined ITA.LI.CA stages (0, A, B1, B2, B3, C) using only tumor characteristics (largest tumor diameter, number of nodules, intra- and extrahepatic macroscopic vascular invasion, extrahepatic metastases). A parametric multivariable survival model was then used to calculate the relative prognostic value of ITA.LI.CA tumor stage, Eastern Cooperative Oncology Group (ECOG) performance status, Child-Pugh score (CPS), and alpha-fetoprotein (AFP) in predicting individual survival. Based on the model results, an ITA.LI.CA integrated prognostic score (from 0 to 13 points) was constructed, and its prognostic power compared with that of other integrated systems (BCLC, HKLC, MESIAH, CLIP, JIS). Median follow-up was 58 mo for Italian patients (interquartile range, 26-106 mo) and 39 mo for Taiwanese patients (interquartile range, 12-61 mo). The ITA.LI.CA integrated prognostic score showed optimal discrimination and calibration abilities in Italian patients. Observed median survival in the training and internal validation sets was 57 and 61 mo, respectively, in quartile 1 (ITA.LI.CA score ≤ 1), 43 and 38 mo in quartile 2 (ITA.LI.CA score 2-3), 23 and 23 mo in quartile 3 (ITA.LI.CA score 4-5), and 9 and 8 mo in quartile 4 (ITA.LI.CA score > 5). Observed and predicted median survival in the training and internal validation sets largely coincided. Although observed and predicted survival estimations were significantly lower (log-rank test, p < 0.001) in Italian than in Taiwanese patients, the ITA.LI.CA score maintained very high discrimination and calibration features also in the external validation cohort. The concordance index (C index) of the ITA.LI.CA score in the internal and external validation cohorts was 0.71 and 0.78, respectively. The ITA.LI.CA score's prognostic ability was significantly better (p < 0.001) than that of BCLC stage (respective C indexes of 0.64 and 0.73), CLIP score (0.68 and 0.75), JIS stage (0.67 and 0.70), MESIAH score (0.69 and 0.77), and HKLC stage (0.68 and 0.75). The main limitations of this study are its retrospective nature and the intrinsically significant differences between the Taiwanese and Italian groups.
The ITA.LI.CA prognostic system includes both a tumor staging-stratifying patients with HCC into six main stages (0, A, B1, B2, B3, and C)-and a prognostic score-integrating ITA.LI.CA tumor staging, CPS, ECOG performance status, and AFP. The ITA.LI.CA prognostic system shows a strong ability to predict individual survival in European and Asian populations.
The Barcelona Clinic Liver Cancer (BCLC) intermediate stage (BCLC B) includes a heterogeneous population of patients with hepatocellular carcinoma (HCC). Recently, in order to facilitate treatment ...decisions, a panel of experts proposed to subclassify BCLC B patients. In this study, we aimed to assess the prognostic capability of the BCLC B stage reclassification in a large cohort of patients with untreated HCC managed by the Italian Liver Cancer Group.
We assessed the prognosis of 269 untreated HCC patients observed in the period 1987-2012 who were reclassified according to the proposed subclassification of the BCLC B stage from stage B1 to stage B4. We evaluated and compared the survival of the various substages.
Median survival progressively decreased from stage B1 (n=65, 24.2%: 25 months) through stages B2 (n=105, 39.0%: 16 months) and B3 (n=22, 8.2%: 9 months), to stage B4 (n=77, 28.6%: 5 months; P<0.0001). Moreover, we observed a significantly different survival between contiguous stages (B1 vs. B2, P=0.0002; B2 vs. B3, P<0.0001; B3 vs. B4, P=0.0219). In multivariate analysis, the BCLC B subclassification (P<0.0001), MELD score (P=0.0013), and platelet count (P=0.0252) were independent predictors of survival.
The subclassification of the intermediate-stage HCC predicts the prognosis of patients with untreated HCC. The prognostic figures identified in this study may be used as a benchmark to assess the efficacy of therapeutic intervention in the various BCLC B substages, whereas it remains to be established whether incorporation of the MELD score might improve the prognosis of treated patients.
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