455 research outputs found

    Are the deficits in navigational abilities present in the Williams syndrome related to deficits in the backward inhibition?

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    Williams syndrome (WS) is associated with a distinct profile of relatively proficient skills within the verbal domain compared to the severe impairment of visuo-spatial processing. Abnormalities in executive functions and deficits in planning ability and spatial working memory have been described. However, to date little is known about the influence of executive function deficits on navigational abilities in WS. This study aimed at analyzing in WS individuals a specific executive function, the backward inhibition (BI) that allows individuals to flexibly adapt to continuously changing environments. A group of WS individuals and a mental age- and gender-matched group of typically developing children were subjected to three task-switching experiments requiring visuospatial or verbal material to be processed. Results showed that WS individuals exhibited clear BI deficits during visuospatial task-switching paradigms and normal BI effect during verbal task-switching paradigm. Overall, the present results suggest that the BI involvement in updating environment representations during navigation may influence WS navigational abilitie

    Dynamics of stripe patterns in type-I superconductors subject to a rotating field

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    The evolution of stripe patterns in type-I superconductors subject to a rotating in-plane magnetic field is investigated magneto-optically. The experimental results reveal a very rich and interesting behavior of the patterns. For small rotation angles, a small parallel displacement of the main part of the stripes and a co-rotation of their very ends is observed. For larger angles, small sideward protrusions develop, which then generate a zigzag instability, ultimately leading to a breaking of stripes into smaller segments. The short segments then start to co-rotate with the applied field although they lag behind by approximately 1010^\circ. Very interestingly, if the rotation is continued, also reconnection of segments into longer stripes takes place. These observations demonstrate the importance of pinning in type-I superconductors.Comment: To appear in Phys. Rev.

    Learning by observation: insights from Williams syndrome.

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    Observing another person performing a complex action accelerates the observer's acquisition of the same action and limits the time-consuming process of learning by trial and error. Observational learning makes an interesting and potentially important topic in the developmental domain, especially when disorders are considered. The implications of studies aimed at clarifying whether and how this form of learning is spared by pathology are manifold. We focused on a specific population with learning and intellectual disabilities, the individuals with Williams syndrome. The performance of twenty-eight individuals with Williams syndrome was compared with that of mental age- and gender-matched thirty-two typically developing children on tasks of learning of a visuo-motor sequence by observation or by trial and error. Regardless of the learning modality, acquiring the correct sequence involved three main phases: a detection phase, in which participants discovered the correct sequence and learned how to perform the task; an exercise phase, in which they reproduced the sequence until performance was error-free; an automatization phase, in which by repeating the error-free sequence they became accurate and speedy. Participants with Williams syndrome beneficiated of observational training (in which they observed an actor detecting the visuo-motor sequence) in the detection phase, while they performed worse than typically developing children in the exercise and automatization phases. Thus, by exploiting competencies learned by observation, individuals with Williams syndrome detected the visuo-motor sequence, putting into action the appropriate procedural strategies. Conversely, their impaired performances in the exercise phases appeared linked to impaired spatial working memory, while their deficits in automatization phases to deficits in processes increasing efficiency and speed of the response. Overall, observational experience was advantageous for acquiring competencies, since it primed subjects' interest in the actions to be performed and functioned as a catalyst for executed action

    Age Diversity Climate Affecting Individual‐Level Work‐Related Outcomes

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    The present study answers the call for more studies to investigate the age diversity climate’s effect on individual‐level outcomes. Building on the social identity approach and social exchange theory, we surveyed 110 Italian employees aged between 18 and 61 years old (M = 46.10, SD = 10.02) and investigated the role of age diversity climate in predicting intentions to quit (H1), job‐related wellbeing (H2), and work engagement (H3). Our findings confirmed the hypotheses (H1 and H2), showing the added effect of age diversity climate over and above age, job tenure, role clarity, job demands, job control, perceived support, and perceived job and organizational fit. In fact, age diversity climate accounted for a significant increase in the variance explained for two of the three hypothesized models (i.e., intentions to quit and job‐related wellbeing, but not work engagement). To conclude, this study contributes to the existing literature by showing the age diversity climate’s predictive value for turnover intentions and job‐related wellbeing, and corroborating the importance of supporting age diversity through a variety of Human Resources Management strategies

    Type-1.5 Superconductors

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    We demonstrate the existence of a novel superconducting state in high quality two-component MgB2 single crystalline superconductors where a unique combination of both type-1 (kappa_1 0.707) superconductor conditions is realized for the two components of the order parameter. This condition leads to a vortex-vortex interaction attractive at long distances and repulsive at short distances, which stabilizes unconventional stripe- and gossamer-like vortex patterns that we have visualized in this type-1.5 superconductor using Bitter decoration and also reproduced in numerical simulations.Comment: accepted in Phys. Rev. Let

    Clinical application of mindfulness-oriented meditation: A preliminary study in children with ADHD

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    Mindfulness-oriented meditation (MOM) is a self-regulatory training used for attentional and behavioral problems. With its focus on attention, MOM is a promising form of training that is gaining empirical support as a complementary or alternative intervention for attention deficit/hyperactivity disorder (ADHD). In this study, we tested the preliminary efficacy of MOM training in children with ADHD, by comparing its efficacy with an active control condition (Emotion Education Program, EEP). Twenty-five children with ADHD aged 7\u201311 years participated in MOM training (n = 15) or EEP (n = 10) 3 times per week for 8 weeks. Neuropsychological and academic measures and behavioral, emotional, and mindfulness ratings were collected before and after the two programs. On average, MOM training had positive effects on neuropsychological measures, as evidenced by a significant mean improvement in all outcome measures after training. Moreover, positive effects on ADHD symptoms were found only in the MOM group. Although they are preliminary, our results documented that MOM training promotes changes in neuropsychological measures and in certain behavioral symptoms, suggesting it as a promising tool for ameliorating cognitive and clinical manifestations of ADHD

    Response to ranibizumab therapy in neovascular AMD - an evaluation of good and bad responders

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    Background: Treatment of neovascular age-related macular degeneration (AMD) with Lucentis® shows a broad spectrum regarding the course of visual acuity (VA). While some patients show a good response (increase in VA), others disclose much less promising results. Patients and Methods: A retrospective data analysis of all eyes treated for neovascular AMD at the University Hospital of Zurich, Switzerland for at least 12 months was carried out. The courses of VA between the 90th (good responders, GR) and the 10th (bad responders, BR) percentiles were compared at 3, 12 and 24 months from baseline. An analysis regarding demographic data, lesion type and size as well as injection frequency and visits was done and predictive factors for GR and BR were evaluated. Results: Marked differences in the course of VA between GR (n = 30) and BR (n = 30) are already observed 3 months from baseline. In GR the gains in VA after 3, 12 and 24 were 15.7 ± 9 letters ETDRS, 25.3 ± 7 and 14.0 ± 14. BR showed a deterioration of 8.3 ± 11 letters ETDRS after 3, 22.1 ± 8 after 12 and 23.6 ± 13 after 24 months. The gender distribution was equal with a higher percentage of female patients (64 % in BR and 66 % in GR). The baseline VA was statistically significantly lower in GR (45.7 ± 10 vs. 55.4 ± 11, p < 0.05) than in BR. No other significant differences in baseline data were found, and no predictor for group membership could be identified. Conclusions: Only the course of VA in the first three months seems to be of value for an estimation of the response to treatment. In the future the response to treatment in the early phase may influence the treatment algorithm and the injection frequency

    Peripersonal Visuospatial Abilities in Williams Syndrome Analyzed by a Table Radial Arm Maze Task

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    Williams syndrome (WS) is a genetic deletion syndrome characterized by severe visuospatial deficits affecting spatial exploration and navigation abilities in extra-personal space.To date, little is known about spatial elaboration and reaching abilities in the peripersonal space in individuals with WS. The present study is aimed at evaluating the visuospatial abilities in individuals with WS and comparing their performances with those of mental age-matched typically developing (TD) children by using a highly sensitive ecological version of the Radial Arm Maze (table RAM). We evaluated 15 individuals with WS and 15 TD children in two different table RAM paradigms: the free-choice paradigm, mainly to analyze the aspects linked to procedural and memory components, and the forced-choice paradigm, to disentangle the components linked to spatial working memory from the procedural ones.Data show that individuals with WS made significantly more working memory errors as compared with TD children, thus evidencing a marked deficit in resolving the task when the mnesic load increased. Our findings provide new insights on the cognitive profile of WS
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