2,052 research outputs found

    Velo-Cardio-Facial Syndrome

    Get PDF
    Purpose of review: Velo-cardio-facial syndrome has emerged from obscurity to become one of the most researched disorders this past decade. It is one of the most common genetic syndromes in humans, the most common contiguous gene syndrome in humans, the most common syndrome of cleft palate, and the most common syndrome of conotruncal heart malformations. Velo-cardio-facial syndrome has an expansive phenotype, a factor reflected in the wide range of studies that cover both clinical features and molecular genetics. In this review, we cover multiple areas of research during the past year, including psychiatric disorders, neuroimaging, and the delineation of clinical features. Recent findings: The identification of candidate genes for heart anomalies, mental illness, and other clinical phenotypes has been reported in the past year with a focus on TBX1 for cardiac and craniofacial phenotypes and COMT and PRODH for psychiatric disorders. The expansive phenotype of velo-cardio-facial syndrome continues to grow with new behavioral and structural anomalies reported. Treatment issues are beginning to draw attention, although most authors continue to focus on diagnostic issues. Summary: Its high population prevalence, estimated to be as common as 1:2000 has sparked a large amount of research, as has the model the syndrome serves for identifying the causes of mental illness and learning disabilities, but it is obvious that more information is needed. Intensive scrutiny of velo-cardio-facial syndrome will undoubtedly continue for many years to come with the hope that researchers will turn more of their attention to treatment and treatment outcomes

    Cognitive and Psychiatric Predictors to Psychosis in Velocardiofacial Syndrome: A 3-Year Follow-Up Study

    Get PDF
    Objective: To predict prodromal psychosis in adolescents with velocardiofacial syndrome (VCFS). Method: 70 youth with VCFS, 27 siblings of youth with VCFS and 25 community controls were followed from childhood (Mean age = 11.8 years) into mid-adolescence (mean age 15.0 years). Psychological tests measuring intelligence, academic achievement, learning/memory, attention and executive functioning as well as measures of parent and clinician ratings of child psychiatric functioning were completed at both time point. Results: Major depressive disorder, oppositional defiant disorder, and generalized anxiety disorder diagnoses increased in the VCFS sample. With very low false positive rates, the best predictor of adolescent prodromal psychotic symptoms was parent ratings of childhood odd/eccentric symptoms and child performance on a measure of executive functioning, the Wisconsin Card Sorting Test. Conclusions: Similar to the non-VCFS prodromal psychosis literature, a combination of cognitive and psychiatric variables appears to predict psychosis in adolescence. A child with VCFS who screens positive is noteworthy and demands clinical attention

    Derivation of an optimal directivity pattern for sweet spot widening in stereo sound reproduction

    Get PDF
    In this paper the correction of the degradation of the stereophonic illusion during sound reproduction due to off-center listening is investigated. The main idea is that the directivity pattern of a loudspeaker array should have a well-defined shape such that a good stereo reproduction is achieved in a large listening area. Therefore, a mathematical description to derive an optimal directivity pattern lopt that achieves sweet spot widening in a large listening area for stereophonic sound applications is described. This optimal directivity pattern is based on parametrized time/intensity trading data coming from psycho-acoustic experiments within a wide listening area. After the study, the required digital FIR filters are determined by means of a least-squares optimization method for a given stereo base setup (two pair of drivers for the loudspeaker arrays and 2.5-m distance between loudspeakers), which radiate sound in a broad range of listening positions in accordance with the derived lopt. Informal listening tests have shown that the lopt worked as predicted by the theoretical simulations. They also demonstrated the correct central sound localization for speech and music for a number of listening positions. This application is referred to as "Position-Independent (PI) stereo.

    Luminosity- and morphology-dependent clustering of galaxies

    Get PDF
    How does the clustering of galaxies depend on their inner properties like morphological type and luminosity? We address this question in the mathematical framework of marked point processes and clarify the notion of luminosity and morphological segregation. A number of test quantities such as conditional mark-weighted two-point correlation functions are introduced. These descriptors allow for a scale-dependent analysis of luminosity and morphology segregation. Moreover, they break the degeneracy between an inhomogeneous fractal point set and actual present luminosity segregation. Using the Southern Sky Redshift Survey~2 (da Costa et al. 1998, SSRS2) we find both luminosity and morphological segregation at a high level of significance, confirming claims by previous works using these data (Benoist et al. 1996, Willmer et al. 1998). Specifically, the average luminosity and the fluctuations in the luminosity of pairs of galaxies are enhanced out to separations of 15Mpc/h. On scales smaller than 3Mpc/h the luminosities on galaxy pairs show a tight correlation. A comparison with the random-field model indicates that galaxy luminosities depend on the spatial distribution and galaxy-galaxy interactions. Early-type galaxies are also more strongly correlated, indicating morphological segregation. The galaxies in the PSCz catalog (Saunders et al. 2000) do not show significant luminosity segregation. This again illustrates that mainly early-type galaxies contribute to luminosity segregation. However, based on several independent investigations we show that the observed luminosity segregation can not be explained by the morphology-density relation alone.Comment: aastex, emulateapj5, 20 pages, 13 figures, several clarifying comments added, ApJ accepte

    Dynamical effects of the neutrino gravitational clustering at Planck angular scales

    Full text link
    We study the CMB anisotropy induced by the non-linear perturbations in the massive neutrino density associated to the non-linear gravitational clustering proceses. Our results show that for the neutrino fraction in agreement with that indicated by the astroparticle and nuclear physics experiments and a cosmological accreting mass comparable with the mass of known clusters, the angular resolution and the sensitivity of the CMB anisotropy measurements from the Planck surveyor will allow the detection of the dynamical effects of the neutrino gravitational clustering.Comment: 40 pages and 12 figures, submitted to ApJ (14 March 2002

    The Neural Correlates of Non-Spatial Working Memory in Velocardiofacial Syndrome (22q11.2 Deletion Syndrome)

    Get PDF
    Velocardiofacial syndrome (VCFS), also known as 22q11.2 deletion syndrome, is a neurogenetic disorder that is associated with both learning disabilities and a consistent neuropsychological phenotype, including deficits in executive function, visuospatial perception, and working memory. Anatomic imaging studies have identified significant volumetric reductions in the parietal lobe of individuals with VCFS, but several studies have reported that the frontal lobe is relatively preserved. We used functional magnetic resonance imaging to investigate the neural correlates of non-spatial working memory in 17 youths with VCFS, 10 of their unaffected siblings, and 10 community controls (with the same proportion of learning disabilities as the VCFS youths). Task performance of siblings tended to be more accurate than children with VCFS, who did not differ from community controls. All three-study groups recruited parietal regions that were equivalent in location and magnitude. Whereas the sibling group also recruited the dorsolateral prefrontal cortex (DLPFC), Broca\u27s area, and anterior cingulate, DLPFC activation was absent in the whole brain analyses of children with VCFS and controls. Moreover, the magnitude of frontal activation in VCFS participants was restricted relative to both siblings and controls. These findings suggest that VCFS participants exhibit frontal hypoactivation that is not attributable to performance. In addition, VCFS children and controls (many with idiopathic learning disabilities) appear to rely on phonological rehearsal to hold information on line instead of the DLPFC. Despite previous anatomic MRI reports of preserved frontal lobe volumes in VCFS therefore, these fMRI findings suggest that the frontal component of the distributed network subserving executive function and working memory may be disrupted in youth with this disorder

    Changing social contracts in climate-change adaptation

    Get PDF
    Risks from extreme weather events are mediated through state, civil society and individual action 1 , 2 . We propose evolving social contracts as a primary mechanism by which adaptation to climate change proceeds. We use a natural experiment of policy and social contexts of the UK and Ireland affected by the same meteorological event and resultant flooding in November 2009. We analyse data from policy documents and from household surveys of 356 residents in western Ireland and northwest England. We find significant differences between perceptions of individual responsibility for protection across the jurisdictions and between perceptions of future risk from populations directly affected by flooding events. These explain differences in stated willingness to take individual adaptive actions when state support retrenches. We therefore show that expectations for state protection are critical in mediating impacts and promoting longer-term adaptation. We argue that making social contracts explicit may smooth pathways to effective and legitimate adaptation

    The Longitudinal Course of Attention Deficit/Hyperactivity Disorder in Velo-Cardio-Facial Syndrome

    Get PDF
    OBJECTIVE: To evaluate predictors of persistence of attention deficit/hyperactivity disorder (ADHD) in a large sample of children with velo-cardio-facial syndrome (VCFS) with and without ADHD followed prospectively into adolescence. STUDY DESIGN: Children with VCFS with (n = 37) and without (n = 35) ADHD who were on average 11 years old at the baseline assessment and 15 years old at the follow-up assessment were comprehensively assessed with structured diagnostic interviews and assessments of behavioral, cognitive, social, school, and family functioning. Control participants both with and without ADHD were also followed prospectively. RESULTS: In adolescence, 65% of children with VCFS continued to have findings consistent with ADHD. Childhood predictors of persistence were higher rates of familial ADHD, having childhood depression, having higher levels of hyperactivity, and a larger number of intrusion errors on a verbal list learning test at baseline. Approximately 15% of children with VCFS who did not have ADHD at Time 1 met diagnostic criteria for ADHD at Time 2. All of these children had subthreshold ADHD symptoms at Time 1. CONCLUSIONS: These findings prospectively confirm that persistence of ADHD into adolescence in VCFS is predicted by childhood variables that have been previously documented in the non-VCFS ADHD literature

    Natural Double Inflation in Supergravity

    Get PDF
    We propose a natural double inflation model in supergravity. In this model, chaotic inflation first takes place by virtue of the Nambu-Goldstone-like shift symmetry, which guarantees the absence of the exponential factor in the potential for the inflaton field. During chaotic inflation, an initial value of the second inflation (new inflation) is set. In this model, the initial value of new inflation can be adequately far from the local maximum of the potential for new inflation due to the small linear term of the inflaton in the K\"ahler potential. Therefore, the primordial fluctuations within the present horizon scale may be attributed to both inflations; that is, the first chaotic inflation produces the primordial fluctuations on the large cosmological scales while the second new inflation on the smaller scales. The successive decay of the inflaton for new inflation leads to a reheating temperature low enough to avoid the overproduction of gravitinos in a wide range of the gravitino mass.Comment: 13 pages, to appear in Phys. Rev.
    • …
    corecore