120 research outputs found
CCD photometric search for peculiar stars in open clusters. VII. Berkeley 11, Berkeley 94, Haffner 15, Lynga 1, NGC 6031, NGC 6405, NGC 6834 and Ruprecht 130
The detection of magnetic chemically peculiar (CP2) stars in open clusters of
the Milky Way can be used to study the influence of different galactic
environments on the (non-)presence of peculiarities, which has to be taken into
account in stellar evolution models. Furthermore it is still unknown if the CP2
phenomenon evolves, i.e. does the strength of the peculiarity feature at 5200A,
increase or decrease with age. We have observed eight young to intermediate age
open clusters in the Delta a photometric system. This intermediate band
photometric system samples the depth of the 5200A, flux depression by comparing
the flux at the center with the adjacent regions having bandwidths of 110A, to
230A. The Delta a photometric system is most suitable to detect CP2 stars with
high efficiency, but is also capable of detecting a small percentage of
non-magnetic CP objects. Also, the groups of (metal-weak) lambda Bootis, as
well as classical Be/shell stars, can be successfully investigated. This
photometric system allows one to determine the age, reddening and distance
modulus by fitting isochrones. Among the presented sample of eight galactic
clusters, we have detected twenty three CP2, eight Be/Ae and eight metal-weak
stars. Another six objects show a peculiar behaviour which is most probably due
to a non-membership,variability or duplicity. Fitting isochrones to Delta a
photometry yields estimates of the age, reddening and distance that are in
excellent agreement with published values
Photometric survey of marginally investigated open clusters: I. Basel 11b, King 14, Czernik 43
To progress in galactic studies based on open clusters, e.g. cluster
formation rate or kinematical properties, one needs to improve the number of
open clusters observed. However, only half of the 1700 known galactic open
clusters have been properly observed so far, making any statistical
investigation insignificant, especially at larger distances from the Sun. We
study marginally investigated or neglected open clusters with Bessell CCD BVR
photometry, whose data were used to fit isochrones to the individual
color-magnitude diagrams. We examined the galactic clusters Basel 11b, King 14
and Czernik 43, the last being observed for the first time to this extent. As
well as a careful comparison to available photometry, their parameters such as
age, interstellar reddening, distance and apparent diameter were determined.
The obtained cluster properties were verified by near infrared 2MASS data. The
three investigated intermediate age clusters are all located in the galactic
disk with distances between 1.8 and 3.0kpc from the Sun.Comment: A&A accepted, 7 pages, 5 figure
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Behaviour sequelae following acute Kawasaki disease.
BACKGROUND: Kawasaki disease is a systemic vasculitis and may affect cerebral function acutely. The aim of the present study was to measure a number of behaviour and social parameters within a cohort of Kawasaki disease patients. METHODS: Parents of children with past diagnosis of Kawasaki disease were recruited to complete several behaviour screening questionnaires. Sixty five sets of questionnaires relating to the patient cohort received were eligible for inclusion. Two control groups were used, a hospital (HC) control and a sibling control (SC) group. RESULTS: 40% of the Kawasaki disease group showed elevated internalising scores in the clinical or borderline-clinical range. This compared with 18% of hospital controls and 13% of sibling controls. Additionally, the Kawasaki disease (KD) group were shown to be experiencing greater overall total difficulties when compared with the controls (KD 13.7, HC 8.6, SC 8.9). The KD group attained higher behavioural scores within the internalising sub-categories of somatic problems (KD 61, HC 57, SC 54) and withdrawn traits (KD 56, HC 53, SC 51). The KD group were also shown to be suffering more thought problems (KD 57, HC 53, SC 50) compared with the controls. Further difficulties relating to conduct (KD 3.3, HC 1.4) and social interactions (KD 6.7, HC 8.3) are also highlighted for the KD group compared with hospital controls. Positron emission tomograms were performed on nine patients to investigate severe behavioural problems. Three showed minor changes, possibly a resolving cerebral vasculopathy. CONCLUSION: Kawasaki disease can be associated with significant behavioural sequelae. This is an important consideration in the long-term follow up and referral to a clinical psychologist may be necessary in selected patients
Pontocerebellar hypoplasia type 2: a neuropathological update
Pontocerebellar hypoplasia type 2 (PCH-2; MIM 277470), an autosomal recessive neurodegeneration with fetal onset, was studied in six autopsies with ages at death ranging between 1 and 22 years. Three patients were distantly related. A case of olivopontocerebellar hypoplasia (OPCH; MIM 225753) was studied for comparison. Typical findings are: short cerebellar folia with poor branching (“hypoplasia”), relative sparing of the vermis, sharply demarcated areas of full thickness loss of cerebellar cortex probably resulting from regression at an early stage of development, segmental loss of dentate nuclei with preserved islands and reactive changes, segmental loss in the inferior olivary nucleus with reactive changes, loss of ventral pontine nuclei with near absence of transverse pontine fibers and sparing of spinal anterior horn cells. Variable findings are: cystic cerebellar degeneration, found in two, with vascular changes limited to the cerebellum in one. Comparison to olivopontocerebellar hypoplasia (OPCH) strongly suggests a continuum of pathology between this disorder and PCH-2. Immunohistochemical evaluation of the endoplasmic reticulum stress response is negative. We conclude that the neuropathological findings in PCH-2 are sufficiently specific to enable an unequivocal diagnosis based on neuropathology
Efeitos de ensino envolvendo equivalência entre palavra ditada, palavra escrita e objeto sobre a inteligibilidade da fala em adolescente com hipoplasia cerebelar
Dentre as muitas estruturas cerebrais envolvidas na linguagem, o ceberelo cumpre um papel importante na coordenação dos movimentos responsáveis pela fala, de modo que qualquer alteração nesta estrutura pode comprometer o desenvolvimento da linguagem oral. Considerando o planejamento do ensino e as intervenções enquanto um fator que pode alterar as expressões fenotípicas impostas pela hipoplasia cerebelar, este estudo de caso teve como objetivo verificar os efeitos de um programa de ensino (envolvendo equivalência entre palavra ditada, palavra escrita e objeto) sobre a inteligibilidade da fala de um adolescente com doze anos, gênero masculino, com hipoplasia cerebelar. As sessões foram conduzidas em contexto clínico e com uso de brinquedos de preferência do participante. O programa consistiu em etapas de avaliação, ensino, pós-testes e retenção, no qual eram apresentadas tarefas de seleção, vocalização, escrita e composição de palavras. Durante a avaliação, observou-se um baixo desempenho em todas as tarefas, especialmente na nomeação de objetos; no decorrer do ensino, as vocalizações foram monitoradas, constatando-se uma gradativa melhora na inteligibilidade da fala quando o participante nomeava objetos, chegando à precisão no pós-testes e retenção. Pode-se concluir que, para o caso apresentado, o fortalecimento da rede de relações entre estímulos e estímulos-ações verbais promovido pelo programa de ensino, favoreceu melhorias na inteligibilidade da fala
45 Jahre Studium, Forschung und Lehre auf dem Gebiet der Forstwissenschaften
SIGLETIB Hannover: RN 9720(9) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
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