490 research outputs found

    Suitability of a constant air temperature lapse rate over an Alpine glacier: testing the Greuell and Böhm model as an alternative

    Get PDF
    Near-surface air temperature, typically measured at a height of 2 m, is the most important control on the energy exchange and the melt rate at a snow or ice surface. It is distributed in a simplistic manner in most glacier melt models by using constant linear lapse rates, which poorly represent the actual spatial and temporal variability of air temperature. In this paper, we test a simple thermodynamic model proposed by Greuell and Böhm in 1998 as an alternative, using a new dataset of air temperature measurements from along the flowline of Haut Glacier d'Arolla, Switzerland. The unmodified model performs little better than assuming a constant linear lapse rate. When modified to allow the ratio of the boundary layer height to the bulk heat transfer coefficient to vary along the flowline, the model matches measured air temperatures better, and a further reduction of the root-mean-square error is obtained, although there is still considerable scope for improvement. The modified model is shown to perform best under conditions favourable to the development of katabatic winds – few clouds, positive ambient air temperature, limited influence of synoptic or valley winds and a long fetch – but its performance is poor under cloudy conditions

    Comparison of academic performance of twins and singletons in adolescence : follow-up study

    Get PDF
    Objectives To determine whether twins in recent cohorts show similar academic performance in adolescence to singletons and to test the effect of birth weight on academic performance in twins and singletons. Design Follow-up study. Setting Denmark. Participants All twins (n = 3411) and a 5% random sample of singletons (n = 7796) born in Denmark during 1986-8. Main outcome measures Test scores in ninth grade (age 15 or 16), birth weight, gestational age at birth, parents’ age, and parents’ education. Results Ninth grade test scores were normally distributed, with almost identical mean and standard deviations for twins and singletons (8.02 v 8.02 and 1.05 v 1.06) despite the twins weighing on average 908 g (95% confidence interval 886 to 930 g) less than the singletons at birth. Controlling for birth weight, gestational age at birth, age at test, and parents’ age and education confirmed the similarity of test scores for twins and singletons (difference 0.04, 95% confidence interval − 0.03 to 0.10). A significant, positive association between test score and birth weight was observed in both twins and singletons, but the size of the effect was small: 0.06-0.12 standard deviations for every kilogram increase in birth weight. Conclusions Although older cohorts of twins have been found to have lower mean IQ scores than singletons, twins in recent Danish cohorts show similar academic performance in adolescence to that of singletons. Birth weight has a minimal effect on academic performance in recent cohorts; for twins this effect is best judged relative to what is a normal birth weight for twins and not for singletons

    From policy to praxis : rethinking comprehensive integrated primary mental health care

    Get PDF
    Bibliography: p. 222-256.In this dissertation I have provided an academic interrogation of the gap between policy principles for comprehensive integrated primary mental health care in South Africa, and the implementation theoreof. I argue, theoreically, that the current add-on approach, which emphasizes care for patients with serious mental illness, will not achieve the vision for comprehensive integrated primary mental health care in South Africa. I suggest that this trajectory is a product of the reformist approach to the implementation of primary health care, and suggest that what is needed is a shift towards a comprehensive discourse of care at the primary level. My research aimed at developing an understanding of how such a shift could be achieved

    Amleds rolle i Saxos Danmarkshistorie

    Get PDF
    Amled's Role in Saxo's History of the DanesSaxo's representation in Gesta Danorum (History of the Danes, c. 1200) of the ancient myths and legends, prehistory and contemporary history of Denmark, should not only be appreciated for its brilliant style and as a source of knowledge on its subject matter. An essential aspect of Saxo's oeuvre is the integration of its narrative qualities into a persuasive political and cultural statement. Saxo's tale justified the established order of a society ruled by his friends and relations. Also, by the richness of his material and his own erudition and literary skills, it gave evidence of the advanced status of the Nordic realm in a European context.The present article demonstrates these qualities by analyzing a particular - and particularly famous - part of Gesta: The tales about Amled - which Shakespeare transformed into the tragedy of Hamlet. By comparing the variants from the medieval tradition, primarily Annales Ryenses, it is shown that in all probability Saxo, in his turn, also transformed a received tradition in order to serve a specific purpose. By altering the circumstances of location and kinship the events of the legend were set in a feudal framework, consistent with the centralized Danish monarchy of Saxo's time. Amled was depicted with the familiar heroic qualities and did perform amazing feats; only in the end he met his destiny, slain in battle and buried in all but oblivion for having declined morally and failed the obligations of fealty to the Danish King. Various means are used in order to render the story, constructed for politically edifying purposes, meaningful to the reader. Firstly, of course, the events are colourful and entertaining. Secondly, the final downfall of Amled is imbued with a mood of sympathy towards a protagonist who, first robbed of his father and rightful position, had displayed courage and ingenuity to regain everything, only in order to lose it all when he was on the verge of perpetual fame, exceeding even that of his likewise splendid ancestors. The circular pattern of the story, curiously spread over two parts of Gesta, and its genuinely human qualities, stand in considerable contrast to many other episodes in Gesta, focused on the lives of kings. Thirdly, the narrative is adorned by allusion to classical material and by directly using material from the same tradition. The fate of Amled's father - a glorious life, ended by treason and finally rewarded by immortal fame - seems somewhat parallel to that of Hercules. The application of this device lends further depth to Amled's own fate, which is the reverse or negative image of the one which befell the superior hero of the classical world. The cunning of Amled, especially seen in the way he used to conceal his mental faculties until the right moment had arrived, may be part of the original legend, but is evidently being illustrated by recycling elements from Livius and Valerius Maximus. The article even discusses the place of the Amled-episode in the entire composition of Gesta as well as the Old English and Norse sources of other vital components of the action. It concludes by restating and affirming the purposeful and deliberate nature of Saxo's writing

    Saxo Grammaticus' forhold til Bibelen: et bidrag til den middelalderlige reception af kristendommens vigtigste skrift

    Get PDF
    Eksempler på Saxos brug af Vulgat