Two-Component Dust in Spherically Symmetric Motion

Two components of spherically symmetric, inhomogeneous dust penetrating each other are introduced as a generalization of the well-known Tolman-Bondi dust solution. The field equations of this model are formulated and general properties are discussed. inhomogeneous Special solutions with additional symmetries - an extra Killing- or homothetic vector - and their matching to the corresponding Tolman-Bondi solution are investigated.Comment: 16 pages, LaTeX, 5 figures, accepted for publication in Class. Quantum Gra

Self-Similarity in General Relativity \endtitle

The different kinds of self-similarity in general relativity are discussed, with special emphasis on similarity of the ``first'' kind, corresponding to spacetimes admitting a homothetic vector. We then survey the various classes of self-similar solutions to Einstein's field equations and the different mathematical approaches used in studying them. We focus mainly on spatially homogenous and spherically symmetric self-similar solutions, emphasizing their possible roles as asymptotic states for more general models. Perfect fluid spherically symmetric similarity solutions have recently been completely classified, and we discuss various astrophysical and cosmological applications of such solutions. Finally we consider more general types of self-similar models.Comment: TeX document, 53 page

Atherosclerotic pattern of coronary myocardial bridging assessed with CT coronary angiography

The aim of our study was to evaluate the atherosclerotic pattern of patients with coronary myocardial bridging (MB) by means of CT Coronary Angiography (CT-CA). 254 consecutive patients (166 male, mean age 58.6 ± 10.3) who underwent 64-slice CT-CA according to current clinical indications were reviewed for the presence of MB and concomitant segmental atherosclerotic pattern. Coronary plaques were assessed in all patients enrolled. 73 patients (29%) presented single (90%) or multiple (10%) MB, frequently (93%) localized in the mid-distal left anterior descending artery. The MB segment was always free of atherosclerosis. Segments proximal to the MB presented: no atherosclerotic disease (n = 37), positive remodeling (n = 23), 50% stenoses (n = 7). Distal segments presented a different atherosclerosis pattern (P < 0.0001): absence of disease (n = 73), no significant lesions (n = 8). No significant differences were found between segments proximal to MB and proximal coronary segments apart from left main trunk. Pattern of atherosclerotic lesions located in segments 6 and 7 significantly differs between patients with MB and patients without MB (P < 0.05). CT-CA is a reliable method to non-invasively demonstrate MB and related atherosclerotic pattern. CT-CA provides new insight regarding atherosclerosis distribution in segments close to MB

Cognitive Profile of Students Who Enter Higher Education with an Indication of Dyslexia

For languages other than English there is a lack of empirical evidence about the cognitive profile of students entering higher education with a diagnosis of dyslexia. To obtain such evidence, we compared a group of 100 Dutch-speaking students diagnosed with dyslexia with a control group of 100 students without learning disabilities. Our study showed selective deficits in reading and writing (effect sizes for accuracy between d = 1 and d = 2), arithmetic (d≈1), and phonological processing (d>0.7). Except for spelling, these deficits were larger for speed related measures than for accuracy related measures. Students with dyslexia also performed slightly inferior on the KAIT tests of crystallized intelligence, due to the retrieval of verbal information from long-term memory. No significant differences were observed in the KAIT tests of fluid intelligence. The profile we obtained agrees with a recent meta-analysis of English findings suggesting that it generalizes to all alphabetic languages. Implications for special arrangements for students with dyslexia in higher education are outlined

Group membership and racial bias modulate the temporal estimation of in-group/out-group body movements

Social group categorization has been mainly studied in relation to ownership manipulations involving highly-salient multisensory cues. Here, we propose a novel paradigm that can implicitly activate the embodiment process in the presence of group affiliation information, whilst participants complete a task irrelevant to social categorization. Ethnically White participants watched videos of White- and Black-skinned models writing a proverb. The writing was interrupted 7, 4 or 1 s before completion. Participants were tasked with estimating the residual duration following interruption. A video showing only hand kinematic traces acted as a control condition. Residual duration estimates for out-group and control videos were significantly lower than those for in-group videos only for the longest duration. Moreover, stronger implicit racial bias was negatively correlated to estimates of residual duration for out-group videos. The underestimation bias for the out-group condition might be mediated by implicit embodiment, affective and attentional processes, and finalized to a rapid out-group categorization

Monitoreo del progreso del alumno en la identificación de riesgo en la lectura

Este estudo tem por nalidade analisar o uso da monitorização com base no currículo como sistema escolar de identi cação de alunos em risco na leitura, no contexto de um modelo educativo baseado no grau de resposta à intervenção. Realizou-se uma investigação quantitativa em que participaram todos os alunos do 3o ano (82 alunos) de um agrupamento de escolas do norte de Portugal. O tratamento de dados foi feito com recurso à estatística descritiva e inferencial. Destacam-se, entre outras conclusões, a existência de dez alunos em risco na leitura durante todo o ano letivo e o facto de, no nal do 3o ano de escolaridade, a média de resultados dos alunos que nunca estiveram em risco ser superior ao dobro da média de resultados dos alunos que estiveram em risco todo o ano.This study aims to analyze the use of curriculum-based monitoring as a school system to identify students at risk in reading, in the context of an educational model based on the degree of response to intervention. A quantitative investigation was conducted with all third grade students (82 students) from a group of schools in the north of Portugal. Data processing was done using descriptive and inferential statistics. Among the conclusions, the following stand out: the existence of ten students at risk in reading throughout the school year and the fact that, at the end of the third year of schooling, the mean results of students who were never at risk was more than double the mean results of students who were at risk for the entire year.Cette étude a pour but d’analyser l’usage du contôle ayant pour base le coursus comme système scolaire d’identification des élèves présentant des risques dans la lecture, dans le contexte d’un modèle éducatif fondé sur le degrée de réponse à l’intervention. On a fait une investigation quantitative à laquelle ont participé tous les élèves de CM1 (82 élèves) d’un groupement d’écoles du nord du Portugal. Le traitement des données a été fait à l’aide de la statistique descriptive et inférentielle. On souligne, entre autres conclusions, l’existence de dix élèves en risque dans la lecture pendant toute l’année scolaire et le fait qu’à la fin de la troisièmme année de scolarité, la moyenne des résultats des élèves n’ayant jamais été en risque soit supérieur au double de la moyenne des résultats des élèves qui ont été en risque toute l’année.Este estudio tiene la finalidad de analizar el uso del monitoreo del currículo como sistema escolar de identificación de alumnos en riesgo en la lectura, en el marco de un modelo educativo basado en el grado de respuesta a la intervención. Se llevó a cabo una investigación cuantitativa en la que participaron todos los alumnos del 3er año (82 alumnos) de un agrupamiento de escuelas del norte de Portugal. El tratamiento de datos se efectuó por medio de la estadística descriptiva e de inferencias. Se destacan, entre otras conclusiones, la existencia de diez alumnos en riesgo en la lectura durante todo el año lectivo y el hecho de que, al final del 3er año de escolaridad, el promedio de resultados de los alumnos que nunca estuvieron en riesgo era superior al doble del promedio de resultados de los alumnos que estuvieron en riesgo todo el año.(undefined)info:eu-repo/semantics/publishedVersio