An integrative framework for the appraisal of coloration in nature

The world in color presents a dazzling dimension of phenotypic variation. Biological interest in this variation has burgeoned, due to both increased means for quantifying spectral information and heightened appreciation for how animals view the world differently than humans. Effective study of color traits is challenged by how to best quantify visual perception in nonhuman species. This requires consideration of at least visual physiology but ultimately also the neural processes underlying perception. Our knowledge of color perception is founded largely on the principles gained from human psychophysics that have proven generalizable based on comparative studies in select animal models. Appreciation of these principles, their empirical foundation, and the reasonable limits to their applicability is crucial to reaching informed conclusions in color research. In this article, we seek a common intellectual basis for the study of color in nature. We first discuss the key perceptual principles, namely, retinal photoreception, sensory channels, opponent processing, color constancy, and receptor noise. We then draw on this basis to inform an analytical framework driven by the research question in relation to identifiable viewers and visual tasks of interest. Consideration of the limits to perceptual inference guides two primary decisions: first, whether a sensory-based approach is necessary and justified and, second, whether the visual task refers to perceptual distance or discriminability. We outline informed approaches in each situation and discuss key challenges for future progress, focusing particularly on how animals perceive color. Given that animal behavior serves as both the basic unit of psychophysics and the ultimate driver of color ecology/evolution, behavioral data are critical to reconciling knowledge across the schools of color research.

Artificial selection for food colour preferences

Colour is an important factor in food detection and acquisition by animals using visually based foraging. Colour can be used to identify the suitability of a food source or improve the efficiency of food detection, and can even be linked to mate choice. Food colour preferences are known to exist, but whether these preferences are heritable and how these preferences evolve is unknown. Using the freshwater fish Poecilia reticulata, we artificially selected for chase behaviour towards two different-coloured moving stimuli: red and blue spots. A response to selection was only seen for chase behaviours towards the red, with realized heritabilities ranging from 0.25 to 0.30. Despite intense selection, no significant chase response was recorded for the blue-selected lines. This lack of response may be due to the motion-detection mechanism in the guppy visual system and may have novel implications for the evolvability of responses to colour-related signals. The behavioural response to several colours after five generations of selection suggests that the colour opponency system of the fish may regulate the response to selection.

Visual demands in modern Australian primary school classrooms

BACKGROUND: The visual demands of modern classrooms are poorly understood yet are relevant in determining the levels of visual function required to perform optimally within this environment. METHODS: Thirty-three Year 5 and 6 classrooms from eight south-east Queensland schools were included. Classroom activities undertaken during a full school day (9 am to 3 pm) were observed and a range of measurements recorded, including classroom environment (physical dimensions, illumination levels), text size and contrast of learning materials, habitual working distances (distance and estimated for near) and time spent performing various classroom tasks. These measures were used to calculate demand-related minimum criteria for distance and near visual acuity, contrast and sustained use of accommodation and vergence. RESULTS: The visual acuity demands for distance and near were 0.33 ± 0.13 and 0.72 ± 0.09 logMAR, respectively (using habitual viewing distances and smallest target sizes) or 0.33 ± 0.09 logMAR assuming a 2.5 times acuity reserve for sustained near tasks. The mean contrast levels of learning materials at distance and near were greater than 70 per cent. Near tasks (47 per cent) dominated the academic tasks performed in the classroom followed by distance (29 per cent), distance to near (15 per cent) and computer-based (nine per cent). On average, children engaged in continuous near fixation for 23 ± 5 minutes at a time and during distance-near tasks performed fixation changes 10 ± 1 times per minute. The mean estimated habitual near working distance was 23 ± 1 cm (4.38 ± 0.24 D accommodative demand) and the vergence demand was 0.86 ± 0.07(Δ) at distance and 21.94 ± 1.09(Δ) at near assuming an average pupillary distance of 56 mm. CONCLUSIONS: Relatively high levels of visual acuity, contrast demand and sustained accommodative-convergence responses are required to meet the requirements of modern classroom environments. These findings provide an evidence base to inform prescribing guidelines and develop paediatric vision screening protocols and referral criteria.

Urban growth centres on the periphery : ad hoc policy vision and research neglect

The focus of this paper is peripheral urban growth centres on the edges of capital cities in Australia and the challenges they face as dormitory suburbs attempting to establish their own local business development. These challenges create dilemmas as infrastructure and climate change place pressure on long commuting times, while developing strong locally based communities is limited by many resource and demand constraints. The main research question is to examine how these challenges are being addressed in both public policy and academic research. Two propositions emerge from this analysis. The first is that, despite clear recognition of these challenges by public policy makers, there is a lack of coherent policy vision in addressing the dilemmas that are facing these urban growth centres. The second is that, despite all the concerns and lack of policy vision, there is a dearth of useful academic research in Australia to understand the dilemmas and provide guidance for appropriate policy options. In the context of ad hoc policy and academic neglect; Casey, Melton and Wyndham are the three major urban peripheral local government areas in Victoria that are profiled in this paper. They serve as examples in examining incoherence of policy and then analysing the elements that are needed for effective and strong peripheral growth centres that could propel these centres towards efficient and equitable liveable communities. A broad composite model of regional economic development is used to examine the attendant problems in these urban centres and the various viable policy options for addressing these problems. In the process, this paper aims to provide a basis for further rigorous academic investigation of peripheral urban growth centres in Australia and, arising from this, more coherent policies for the economic development of such centres.

3D depth estimation using wavelet analysis based stereo vision approach

A complete and highly robust 3D reconstruction algorithm based on stereo vision is presented. The developed system is capable of reconstructing dimensionally accurate 3D models of the objects and is very simple and cost effective due to its prominent software dependency and minimal hardware involvevment unlike existing systems.

Mobility and vision for mobile robots in non-deterministic, competitive environments

Develops an award winning design for an omnidirectional mobile robot that is both lightweight and extremely maneuverable. Two methods of robot vision, one using rotating lasers and a second using color video cameras were also developed and the merits of both explored.

A representation-intensive signature pedagogy for school science?

In this paper we examine Shulman’s notion of signature pedagogies for its usefulness extended to school science. We argue that school science is in an important sense an apprenticeship, and that calls for reform in school science are compatible with Shulman’s practice-based vision of professional learning. Two case studies of teaching and learning will be presented based on research in primary and secondary schools that involved working closely with teachers to develop and validate involving a representation-intensive pedagogy that lays claim to bringing school science closer to the knowledge building practices of science. Video images of classrooms, interviews with students and teachers, and documentation of students’ work, were used to construct insights into the teaching and learning process. It is argued that Shulman’s notion of professional practice as involving apprenticeships of knowledge, practice and identity provides a useful lens through which to view this innovation. Shulman’s characterisation of signature pedagogy is used to identify key features of the approach.

A method for stereo-vision based tracking for robotic applications

Vision based tracking of an object using the ideas of perspective projection inherently consists of nonlinearly modelled measurements although the underlying dynamic system that encompasses the object and the vision sensors can be linear. Based on a necessary stereo vision setting, we introduce an appropriate measurement conversion techniques which subsequently facilitate using a linear filter. Linear filter together with the aforementioned measurement conversion approach conforms a robust linear filter that is based on the set values state estimation ideas; a particularly rich area in the robust control literature. We provide a rigorously theoretical analysis to ensure bounded state estimation errors formulated in terms of an ellipsoidal set in which the actual state is guaranteed to be included to an arbitrary high probability. Using computer simulations as well as a practical implementation consisting of a robotic manipulator, we demonstrate our linear robust filter significantly outperforms the traditionally used extended Kalman filter under this stereo vision scenario. © 2008 IEEE.

Eye tracking the sublime in spectacular moments of science fiction film

In this chapter I will explore science fiction film spectacle as a particular type of endangering sensorial experience. Employing eye-tracking technology to assess where a small group of viewers look, I will contend that through its spectacular set pieces, science fiction film creates two distinct gazing regimes. First, such spectacular scenes create an experience of sublime contemplation where the viewer is (haptically) lost in the wondrous images liquefying before them. These moments of sublime contemplation create the condition where the viewer feels as if they have had an outer-body experience; one that has been cut free from the borders of the linguistic-led self of everyday life. Second, I will argue that certain scenes of science fiction spectacle work to commodify the viewing experience, creating a gazing pattern that is ‘driven’ by the mechanics of the event moment, by the theme park ride aesthetic and the logic of late capitalism. Set in this sensible, empirical context, the sublime dangers of science fiction film can be considered in two distinct ways. On the one hand, when the viewer is caught gazing in a moment of sublime contemplation there is embodied transgression and transcendence: here I will postulate that the viewer exists purely as a carnal being, or are newly if momentarily constituted as post-human, in the impossible present or possible future world that has been spectacularly imagined for them. On the other hand, when the viewer is presented with a spectacle that demands attention to the mechanics and drivers of the scene as it unfolds, a viewing position is created where the very rhythms of the theme park ride is created, where capitalist life is simply being re-engineered. Sublime and spectacular science fiction endangerment, then, liberates and destroys, and it is the encounter between these two vexing poles that is of central concern in this chapter. My focus will predominately be on the eyes, on vision. Undertaking a small-scale empirical study that uniquely utilizes eye tracking technology, this chapter will concentrate on what viewers attend to, gaze at and ‘contemplate’ when viewing two differently constituted ‘spectacle’ sequences: the sun explodes scene from Sunshine (Boyle, 2007) and the Godzilla enters Manhattan scene from Godzilla (Emmerich, 1998).

From the 'mad' poet to the 'embodied' poet: reconceptualising creativity through cognitive science paradigms

 Written by the author of three collections of poetry, this paper contests the enduring stereotype of the ‘mad’ poet, present in Romantic, psychoanalytic and psychological theories of creativity. Mobilising theories of embodied cognition, it offers a demystified and de-pathologised vision of poiesis and poetry. The paper focuses on three traits typically associated with the ‘mad’ poet in popular representations and theoretical understandings of that figure: extreme emotionality; divergent thinking; and a tortured unconscious. Using findings in the cognitive sciences, the essay demonstrates how emotional experience, divergent thinking, and the unconscious are integral parts of brain functioning, rather than traits exclusive to psychopathology. Poiesis is not informed, in any essential way, by madness but rather by the normal conditions of embodied cognition.

Visual impairment in Australia: distance visual acuity, near vision, and visual field findings of the Melbourne Visual Impairment Project

PURPOSE: To describe the age-specific and gender-specific rates of blindness and visual impairment in urban adults aged 40 years and older. METHODS: A population-based sample of residents was recruited. Presenting and best-corrected distance visual acuities were assessed. Functional near vision was measured at each participant's preferred distance. Visual field examination was performed with a Humphrey Field Analyzer (HFA); those unable to perform the field analyzer test attempted a Bjerrum screen or confrontation field. RESULTS: The study population comprised 3,271 residents (83% of eligible) from ages 40 to 98 years; 54% were women. Overall, 56% of the study population wore distance correction; this was significantly lower in men but higher in the older age groups. Age-adjusted rates of blindness were 0.066% in men and 0.170% in women. Vision with current correction improved after refraction by gender and age. Direct age-standardized rates of functional near vision did not vary significantly by gender. Forty-six people had significant visual field loss in their better eye. The proportion of participants with constriction of the visual field to within 20 degrees of fixation was similar for men and women when controlled for age (odds ratio, 0.81; 95% confidence interval, 0.44 to 1.49) but increased significantly with age controlled for gender. Visual field abnormalities were detected in 548 right eyes (17%) and 533 left eyes (16%). CONCLUSIONS: Although overall rates of blindness because of visual acuity loss were relatively low, nearly three times more people had visual impairment because of visual field loss than visual acuity loss. These results highlight the need to target blindness prevention programs to the aging population, with a special emphasis on women.

Illness cognitions and coping self-efficacy in depression among persons with low vision

PURPOSE: To investigate the mediating role of coping self-efficacy (CSE) between two types of illness cognitions (i.e., acceptance and helplessness) and depressive symptoms in persons with low vision.

METHODS: This was a single-group, cross-sectional study. Patients with visual acuity < 6/12 in the better eye and at least minimal depressive symptoms (≥5 on the Patient Health Questionnaire-9 [PHQ-9]) were recruited from vision rehabilitation services and participated in telephone-administered structured interviews at one time point. Measures were the PHQ-9, CSE Scale, and Illness Cognition Questionnaire. Structural equation modeling (SEM) devised the causal flow of illness cognitions and their observed indirect effects on depressive symptoms via the CSE mediators: problem focused, emotion focused, and social support.

RESULTS: The study comprised 163 patients (mean age 62 years; 61% female), most with age-related macular degeneration (26%) and moderate vision impairment (44%, <6/18-6/60). Structural equation modeling indices indicated a perfect fit (χ2 < 0.001, P = 1.00), accounting for 55% of the variance in depressive symptoms. Lower levels of acceptance and higher levels of helplessness illness cognitions were associated with lower self-efficacy in problem-focused coping (β = 0.38, P < 0.001, β = -0.28, P < 0.01, respectively), which in turn was associated with greater depressive symptom severity (β = -0.54, P < 0.001).

CONCLUSIONS: Lack of acceptance and greater helplessness relating to low vision led to a lack of perceived capability to engage in problem-focused coping, which in turn promoted depressive symptoms. Third-wave cognitive-behavioral treatments that focus on acceptance may be efficacious in this population.