17 resultados para change of colour


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Background: The aim was to investigate the visual effect of coloured filters compared to transmission-matched neutral density filters, in patients with dry age-related macular degeneration. Methods: Visual acuity (VA, logMAR), contrast sensitivity (Pelli-Robson) and colour vision (D15) were recorded for 39 patients (average age 79.1 ± 7.2 years) with age-related macular degeneration, both in the presence and absence of glare from a fluorescent source. Patients then chose their preferred coloured and matched neutral density transmission filters (NoIR). Visual function tests were repeated with the chosen filters, both in the presence and absence of glare from the fluorescent source. Patients trialled the two filters for two weeks each, in random order. Following the trial of each filter, a telephone questionnaire was completed. Results: VA and contrast sensitivity were unaffected by the coloured filters but reduced through the neutral density filters (p < 0.01). VA and contrast sensitivity were reduced by similar amounts, following the introduction of the glare source, both in the presence and absence of filters (p < 0.001). Colour vision error scores were increased following the introduction of a neutral density filter (from 177.6 ± 60.2 to 251.9 ± 115.2) and still further through coloured filters (275.1 ± 50.8; p < 0.001). In the absence of any filter, colour vision error scores increased by 29.1 ± 55.60 units in the presence of glare (F2,107 = 3.9, p = 0.02); however, there was little change in colour vision error scores, in the presence of glare, with either the neutral density or coloured filters. Questionnaires indicated that patients tended to gain more benefit from the coloured filters. Conclusions: Coloured filters had minimal impact on VA and contrast sensitivity in patients with age-related macular degeneration; however, they caused a small reduction in objective colour vision, although this was not registered subjectively by patients. Patients indicated that they received more benefit from the coloured filters compared with neutral density filters. © 2013 The Authors © 2013 Optometrists Association Australia.

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Purpose - This paper aims to examine the usefulness of organizational change theory for management practice. Design/methodology/approach - The authors present an exploratory, empirical study of managers who were taught organizational change theory as part of a postgraduate degree. Building on the study findings, they analyse managers' subsequent experiences of organizational change; of how they use change theory in practice and the impact on their practice of their earlier formal study. Findings - The paper finds that the complexities of managing change in practice reflect distinctive organizational environments and cultures. The skills and knowledge which managers found most useful were those that enabled them to "make sense" of the organizational change they subsequently experienced. The main impact of their earlier studies was to prompt informative, discursive and reflective approaches to change management. Practical implications - The paper discusses the implications for future teaching of organizational change and the development of organizational change theory. Originality/value - The qualitative findings of the study add to, and help to explain, earlier research findings on the questions of how managers' experience change, how they use organizational change theory and its impact on their practice. © Emerald Group Publishing Limited.