Purpose: To establish age-related, normal limits of monocular and binocular spatial vision under photopic and mesopic conditions. Methods: Photopic and mesopic visual acuity (VA) and contrast thresholds (CTs) were measured with both positive and negative contrast optotypes under binocular and monocular viewing conditions using the Acuity-Plus (AP) test. The experiments were carried out on participants (age range from 10 to 86 years), who met pre-established, normal sight criteria. Mean and ± 2.5σ limits were calculated within each 5-year subgroup. A biologically meaningful model was then fitted to predict mean values and upper and lower threshold limits for VA and CT as a function of age. The best-fit model parameters describe normal aging of spatial vision for each of the 16 experimental conditions investigated. Results: Out of the 382 participants recruited for this study, 285 participants passed the selection criteria for normal aging. Log transforms were applied to ensure approximate normal distributions. Outliers were also removed for each of the 16 stimulus conditions investigated based on the ±2.5σ limit criterion. VA, CTs and the overall variability were found to be age-invariant up to ~50 years in the photopic condition. A lower, age-invariant limit of ~30 years was more appropriate for the mesopic range with a gradual, but accelerating increase in both mean thresholds and intersubject variability above this age. Binocular thresholds were smaller and much less variable when compared to the thresholds measured in either eye. Results with negative contrast optotypes were significantly better than the corresponding results measured with positive contrast (p < 0.004). Conclusions: This project has established the expected age limits of spatial vision for monocular and binocular viewing under photopic and high mesopic lighting with both positive and negative contrast optotypes using a single test, which can be implemented either in the clinic or in an occupational setting.
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Significant factors in the success or failure of energy transition arise from the spatial potential of places and their communities. Scenario planning appears to be an appropriate design instrument to enable architects to unveil, conceptualise, imagine, test and communicate this potential to stakeholders. This paper critically refelcts on the scenario as an architectural design instrument. Inscribed with political intentions, scenario planning may be a far from neutral design instrument. Instead of triggering communities to explore local energy potential, a scenario may have a normative effect on a community's imagination. The paper aims to define guidelines for the deployment of scenarios in an open, participatory planning process. To mediate in a local participatory planning process, we argue, scenarios should be situational, dynamic and open-ended, allowing or even triggering communities to (re)define the issues relevant to a place during the ongoing process of energy-transition. How, when and where should scenarios be deployed in order to enable communities to understand and develop their local energy potential?
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For over 30 years, the concept of home has been a popular, yet contested subject of research for scholars from different disciplines, e.g. architecture, philosophy, sociology, psychology and cultural studies. In line with this multifaceted, interesting subject, quite some studies have been devoted to the subject of homemaking.However, when reviewing the literature on home and homemaking, a great deal of scholars seems to have overlooked to date the home situation, and thus the homemaking activities and practices of single person households, or so called ‘solo livers’. This is remarkable because the number of single person households is increasing worldwide, as different recent studies show e.g. (Palmer G. , 2006), (Klinenberg, 2012), (Jamieson & Simpson, 2013). The aim of this working paper – which is part of a PhD proposal in progression – is to address the homemaking process from the perspective of solo living people in the geographical setting of the Provence of Groningen, in the northern part of the Netherlands. An underlying assumption is that by focusing on the homemaking of solo living people, i.e. on the individual level, this typical human phenomenon can be studied in its ‘purest form’.In the paper on homemaking in low-cost areas, Aziz & Ahmad (2012) connect the concepts of appropriation, attachment and identity as homemaking mechanisms, through which residents strive to achieve satisfaction and turn the surrounding area into their home. Aziz & Ahmad seek to identify specific behavioural components, called ‘attributes’, that belong to these three different concepts, in which they make a distinction between physical and social attributes. This focus of this paper is on the concept of appropriation as homemaking mechanism and how this concept can be refined to serve as conceptual framework.
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