10,447 research outputs found

    Stability improvement of PMMA and Lumogen® coatings for hybrid white LEDs

    Get PDF
    Hybrid white LEDs employing perylene-based dyes for the frequency down-conversion of blue light, generated by a standard inorganic source, suffer from colour rendering variations due to the degradation of the organic molecule under prolonged irradiation. To avoid such inconvenient, proper encapsulation of the dyes in resins or other polymer matrices can prevent their accelerated ageing; nevertheless, embedding polymers can also exhibit significant bleaching caused by chemico-physical agents. Among all, polymethyl methacrilate (PMMA) is one of the most used materials for the fabrication of hybrid LEDs' colour conversion coatings, therefore its stability needs to be investigated

    Parent and self-report health-related quality of life measures in young patients with Tourette syndrome

    Get PDF
    Tourette syndrome is a neurodevelopmental disorder characterized by tics and comorbid behavioral problems. This study compared child- and parent-reported quality of life and everyday functioning. We assessed 75 children with Tourette syndrome, of which 42 (56%) had comorbid conditions (obsessive-compulsive disorder = 25; attention-deficit hyperactivity disorder = 6; both comorbidities = 4). All patients completed psychometric instruments, including the Gilles de la Tourette Syndrome-Quality of Life Scale for Children and Adolescents (child report) and the Child Tourette's Syndrome Impairment Scale (parent report). Data were compared for patients with pure Tourette syndrome, Tourette syndrome + obsessive-compulsive disorder, Tourette syndrome + attention-deficit hyperactivity disorder, and Tourette syndrome + both comorbidities. There were no group differences in quality of life. However, there were differences for total, school, and home activities impairment scores. Children and parents may not share similar views about the impact of Tourette syndrome on functioning. The measurement of health-related quality of life in Tourette syndrome is more complex in children than adults

    Lectura de pseudopalabras en árabe y español

    Get PDF
    El objetivo de este estudio consiste en analizar las diferencias entre la lectura de palabras en alumnos ecuatorianos y argelinos en Educación Primaria. La muestra está formada por un grupo de 128 alumnos de una escuela de Ecuador y por otro grupo de 113 alumnos de una escuela de Argel, pertenecientes a una clase social media y sin necesidades educativas especiales. Los participantes fueron evaluados en lectura de pseudopalabras en primero y segundo curso de Educación Primaria. Las palabras utilizadas en español fueron adaptadas al árabe, teniendo en cuenta la longitud y frecuencia de cada una de ellas en esta lengua. Se llevó a cabo un diseño factorial mixto 2x2, donde el factor intersujeto fue el tipo de lengua según la consistencia ortográfica (transparente y opaca) y el factor intrasujeto el nivel educativo (primero y segundo curso de educación primaria). Los resultados del ANOVA de medidas repetidas en un factor muestran efectos significativos de ambos factores (tipo de lengua y nivel educativo) y de su interacción. Se encontró mejor precisión lectora de pseudopalabras en los niños de lengua árabe en ambos niveles educativos, un aumento de la lectura de pseudopalabras entre los dos cursos en las dos lenguas, siendo más intenso en español, y una menor diferencia en lectura de pseudopalabras entre lenguas en segundo curso. Estos resultados van en la línea de aquellos estudios que defienden las diferencias en la adquisición de la lectura en lenguas de distinta consistencia, pero no concuerdan con aquellos que apuntan que las lenguas opacas son más tardías. Se resalta la necesidad de analizar las diferencias en otras edades más tempranas y en otras medidas lectoras, controlando el grado de consistencia lingüística.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    A Coding Variant in the Gene Bardet-Biedl Syndrome 4 (BBS4) Is Associated with a Novel Form of Canine Progressive Retinal Atrophy

    Get PDF
    Progressive retinal atrophy is a common cause of blindness in the dog and affects >100 breeds. It is characterized by gradual vision loss that occurs due to the degeneration of photoreceptor cells in the retina. Similar to the human counterpart retinitis pigmentosa, the canine disorder is clinically and genetically heterogeneous and the underlying cause remains unknown for many cases. We use a positional candidate gene approach to identify putative variants in the Hungarian Puli breed using genotyping data of 14 family-based samples (CanineHD BeadChip array, Illumina) and whole-genome sequencing data of two proband and two parental samples (Illumina HiSeq 2000). A single nonsense SNP in exon 2 of BBS4 (c.58A > T, p.Lys20*) was identified following filtering of high quality variants. This allele is highly associated (P-CHISQ = 3.425e(-14), n = 103) and segregates perfectly with progressive retinal atrophy in the Hungarian Puli. In humans, BBS4 is known to cause Bardet-Biedl syndrome which includes a retinitis pigmentosa phenotype. From the observed coding change we expect that no functional BBS4 can be produced in the affected dogs. We identified canine phenotypes comparable with Bbs4-null mice including obesity and spermatozoa flagella defects. Knockout mice fail to form spermatozoa flagella. In the affected Hungarian Puli spermatozoa flagella are present, however a large proportion of sperm are morphologically abnormal andPeer reviewe

    Beam Test Performance and Simulation of Prototypes for the ALICE Silicon Pixel Detector

    Full text link
    The silicon pixel detector (SPD) of the ALICE experiment in preparation at the Large Hadron Collider (LHC) at CERN is designed to provide the precise vertex reconstruction needed for measuring heavy flavor production in heavy ion collisions at very high energies and high multiplicity. The SPD forms the innermost part of the Inner Tracking System (ITS) which also includes silicon drift and silicon strip detectors. Single assembly prototypes of the ALICE SPD have been tested at the CERN SPS using high energy proton/pion beams in 2002 and 2003. We report on the experimental determination of the spatial precision. We also report on the first combined beam test with prototypes of the other ITS silicon detector technologies at the CERN SPS in November 2004. The issue of SPD simulation is briefly discussed.Comment: 4 pages, 5 figures, prepared for proceedings of 7th International Position Sensitive Detectors Conference, Liverpool, Sept. 200
    corecore