210 resultados para Following distance.


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Fire has long been recognized as an agent of rock weathering. Our understanding of the impact of fire on stone comes either from early anecdotal evidence, or from more recent laboratory simulation studies, using furnaces to simulate the effects of fire. This paper suggests that knowledge derived from simulated heating experiments is based on the preconceptions of the experiment designer – when using a furnace to simulate fire, the operator decides on the maximum temperature and the duration of the experiment. These are key factors in determining the response of the stone to fire, and if these are removed from realworld observations then knowledge based on these simulations must be questioned. To explore the differences between heating sandstone in a furnace and a real fire, sample blocks of Peakmoor Sandstone were subjected to different stress histories in combination (lime rendering and removal, furnace heating or fire, frost and salt weathering). Block response to furnace heating and fire is discussed, with emphasis placed on the non-uniformity of the fire and of block response to fire in contrast to the uniform response to surface heating in a furnace. Subsequent response to salt weathering (by a 10% solution of sodium chloride and magnesium sulphate) was then monitored by weight loss. Blocks that had experienced fire showed a more unpredictable response to salt weathering than those that had undergone furnace heating – spalling of corners and rapid catastrophic weight loss were evidenced in blocks that had been subjected to fire, after periods of relative quiescence. An important physical side-effect of the fire was soot accumulation, which created a waxy, relatively impermeable layer on some blocks. This layer repelled water and hindered salt ingress, but eventually detached when salt, able to enter the substrate through more permeable areas, concentrated and crystallized behind it, resulting in rapid weight loss and accelerated decay. Copyright ©2007 John Wiley & Sons, Ltd.

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A sub-chronic administration of phencyclidine to the rat brings about enduring pathophysiological and cognitive changes that resemble some features of schizophrenia. The present study aimed to determine whether the behavioural consequence of this phencyclidine regime extends to a long-term disruption of social interaction that might provide a parallel with some negative symptoms of the disease. Rats were treated with phencyclidine (2mg/kg bi-daily for 1 week) or vehicle followed by a drug-free period. Social interaction was assessed 24h, 1 week, 3 weeks and 6 weeks post-treatment. A long-lasting disturbance of social behaviour was observed in the phencyclidine group, namely more contact and non-contact interaction with an unfamiliar target rat at all time points. Six weeks post-phencyclidine, analysis of brains showed a reduction in expression of parvalbumin immunoreactive neurons in the hippocampus with significant reductions localised to the CA1 and dentate gyrus regions. These results show that sub-chronic phencyclidine produces long-lasting disruptions in social interaction that, however, do not model the social withdrawal seen in patients with schizophrenia. These disturbances of social behaviour may be associated with concurrent pathophysiological brain changes.

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This essay uses the concepts of ‘distance’ and ‘proximity’ to investigate and assess perceptions of community, nation and empire in inter-war New Zealand and Ulster (as well as Ireland and Northern Ireland) within a British imperial context, and explores the extent to which service of the empire (for example in the First World War) promoted both notions of imperial unity and local autonomy. It focuses on how these perceptions were articulated in the inter-war years during visits to Northern Ireland by three New Zealand premiers – Massey, Forbes and Coates – and to New Zealand by the Prime Minister of Northern Ireland, Lord Craigavon. It discusses the significant ways in which distance from their ‘home base’ and proximity to expatriate communities (in Craigavon's case) and Irish unionists and nationalists (in the case of the New Zealand premiers) inflected public statements during their visits. By examining these inter-war visits and investigating the rhetoric used and the cultural demonstrations associated with them, the factors of both distance and proximity can be used to evaluate similarities and difference across two parts of the empire. Thus, we can throw some light on the nature and dynamics of British imperial identity in the early twentieth century.

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Score following has been an important area of research in AI and music since the mid 80's. Various systems were developed, but they were predominantly for providing automated accompaniment to live concert performances, dealing mostly with issues relating to pitch detection and identification of embellished melodies. They have a big potential in the area of education where student performers benefit in practice situations. Current accompaniment systems are not designed to deal with errors that may occur during practising. In this paper we present a system developed to provide accompaniment for students practising at home. First a survey of score following will be given. Then the capabilities of the system will be explained, and the results from the first experiments of the monophonic score following system will be presented.

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Aim. The purpose of this experiment was to assess the levels of muscle soreness, serum total cholesterol (TC) and creatine kinase (CK) in the first 48 hours following fatiguing eccentric exercise performed with the triceps brachii.