Sunglasses, traffic signals, and color vision deficiencies

Purpose: To determine (a) the effect of different sunglass tint colorations on traffic signal detection and recognition for color normal and color deficient observers, and (b) the adequacy of coloration requirements in current sunglass standards. Methods: Twenty color-normals and 49 color-deficient males performed a tracking task while wearing sunglasses of different colorations (clear, gray, green, yellow-green, yellow-brown, red-brown). At random intervals, simulated traffic light signals were presented against a white background at 5° to the right or left and observers were instructed to identify signal color (red/yellow/green) by pressing a response button as quickly as possible; response times and response errors were recorded. Results: Signal color and sunglass tint had significant effects on response times and error rates (p < 0.05), with significant between-color group differences and interaction effects. Response times for color deficient people were considerably slower than color normals for both red and yellow signals for all sunglass tints, but for green signals they were only noticeably slower with the green and yellow-green lenses. For most of the color deficient groups, there were recognition errors for yellow signals combined with the yellow-green and green tints. In addition, deuteranopes had problems for red signals combined with red-brown and yellow-brown tints, and protanopes had problems for green signals combined with the green tint and for red signals combined with the red-brown tint. Conclusions: Many sunglass tints currently permitted for drivers and riders cause a measurable decrement in the ability of color deficient observers to detect and recognize traffic signals. In general, combinations of signals and sunglasses of similar colors are of particular concern. This is prima facie evidence of a risk in the use of these tints for driving and cautions against the relaxation of coloration limits in sunglasses beyond those represented in the study.

Effect of optical aberrations on the color appearance of small defocused lights

We investigated influences of optics and surround area on color appearance of defocused, small narrow band photopic lights (1’ arc diameter, λmax 510 - 628 nm) centered within a black annulus and surrounded by a white field. Participants included seven normal trichromats with L- or M-cone biased ratios. We controlled chromatic aberration with elements of a Powell achromatizing lens and corrected higher-order aberrations with an adaptive-optics system. Longitudinal chromatic aberrations, but not monochromatic aberrations, are involved in changing appearance of small lights with defocus. Surround field structure is important because color changes were not observed when lights were presented on a uniform white surround.

Color and texture feature fusion using kernel PCA with application to object-based vegetation species classification

A good object representation or object descriptor is one of the key issues in object based image analysis. To effectively fuse color and texture as a unified descriptor at object level, this paper presents a novel method for feature fusion. Color histogram and the uniform local binary patterns are extracted from arbitrary-shaped image-objects, and kernel principal component analysis (kernel PCA) is employed to find nonlinear relationships of the extracted color and texture features. The maximum likelihood approach is used to estimate the intrinsic dimensionality, which is then used as a criterion for automatic selection of optimal feature set from the fused feature. The proposed method is evaluated using SVM as the benchmark classifier and is applied to object-based vegetation species classification using high spatial resolution aerial imagery. Experimental results demonstrate that great improvement can be achieved by using proposed feature fusion method.

Users verses IT: Understanding prejudice in information systems development project teams

This paper investigated the phenomenon of prejudice among ISD project members. We presented a theoretical discussion followed by one qualitative and one quantitative study. In the qualitative study, we interviewed different members of the project teams to understand the different types of prejudice possessed by team members. Results of this interview study led to the development of prejudice scales for IT members and users, which was used in the quantitative study. We surveyed 128 ISD teams and found that prejudice was related task and relationship conflict, satisfaction and willingness to work together in the future. Furthermore, prejudice exerts stronger influences on users than IT members in terms of increasing task and relationship conflicts and decreasing goal commitment.

The meaning of 'material prejudice'

As dictated by s 213 of the Body Corporate and Community Management Act 1997 (Qld), the seller of a proposed lot is required to provide the buyer with a disclosure statement before the contract is entered into. Where the seller subsequently becomes aware that information contained in the disclosure statement was inaccurate when the contract was entered into or the disclosure statement would not be accurate if now given as a disclosure statement, the seller must, within 14 days, give the buyer a further statement rectifying the inaccuracies in the disclosure statement. Provided the contract has not been settled, where a further statement varies the disclosure statement to such a degree that the buyer would be materially prejudiced if compelled to complete the contract, the buyer may cancel the contract by written notice given to the seller within 14 days, or a longer period as agreed between the parties, after the seller gives the buyer the further statement. The term ‘material prejudice’ was considered by Wilson J in Wilson v Mirvac Queensland Pty Ltd.

Queensland Court of Appeal opines on the meaning of 'material prejudice'

The decision of Wilson J in Wilson v Mirvac Queensland Pty Ltd was the subject of an article in an earlier edition of this journal. At that time, it was foreshadowed that the decision was to be taken on appeal. The decision of the Court of Appeal in Mirvac Queensland Pty Ltd v Wilson is considered in this article.

Review of "Violence, Prejudice and Sexuality" by Stephen Tomsen (Routledge, New York and London, 2009)

Tomsen’s book Violence, Prejudice and Sexuality engages with important questions about sexuality and anti homosexual sentiment that criminologists have grappled with for some time. Tomsen’s work refines these questions in the context of essentialism, and notes how this concept has enabled only very specific ways of thinking about and analysing violence, prejudice, and sexuality. Indeed, thinking about the nexus between these three concepts are now almost taken for granted. As Tomsen demonstrates in his discussion of historical understandings of sexual desire, although social constructionism and queer perspectives have challenged essentialist notions of sexuality, research has in many respects upheld a binary understanding of heterosexuality as normal and homosexuality as abnormal. Interestingly, essentialist binaries like this have been conveniently employed in more recent times when activists align with minority status to gain basic human rights. While no one could deny the importance of access to rights and justice, Tomsen notes the danger inherent in arguments like this that draw on essentialism. He argues we are working through similar dichotomies of heterosexuality as normal and homosexuality as abnormal set up in very early research on sexual desire. The key difference now is that, in the rush towards public and political citizenship, ‘heterosexuals are recast as “perpetrators” and homosexuals as “victims”’ (Tomsen 2009: 16). Violence, Prejudice and Sexuality importantly notes this is no less an essentialist dichotomy and no less divisive....

Adaptive evolution of color vision as seen through the eyes of butterflies

Butterflies and primates are interesting for comparative color vision studies, because both have evolved middle- (M) and long-wavelength- (L) sensitive photopigments with overlapping absorbance spectrum maxima (lambda(max) values). Although positive selection is important for the maintenance of spectral variation within the primate pigments, it remains an open question whether it contributes similarly to the diversification of butterfly pigments. To examine this issue, we performed epimicrospectrophotometry on the eyes of five Limenitis butterfly species and found a 31-nm range of variation in the lambda(max) values of the L-sensitive photopigments (514-545 nm). We cloned partial Limenitis L opsin gene sequences and found a significant excess of replacement substitutions relative to polymorphisms among species. Mapping of these L photopigment lambda(max) values onto a phylogeny revealed two instances within Lepidoptera of convergently evolved L photopigment lineages whose lambda(max) values were blue-shifted. A codon-based maximum-likelihood analysis indicated that, associated with the two blue spectral shifts, four amino acid sites (Ile17Met, Ala64Ser, Asn70Ser, and Ser137Ala) have evolved substitutions in parallel and exhibit significant d(N)/d(S) >1. Homology modeling of the full-length Limenitis arthemis astyanax L opsin placed all four substitutions within the chromophore-binding pocket. Strikingly, the Ser137Ala substitution is in the same position as a site that in primates is responsible for a 5- to 7-nm blue spectral shift. Our data show that some of the same amino acid sites are under positive selection in the photopigments of both butterflies and primates, spanning an evolutionary distance >500 million years.

Book review: ‘Cornea. Color Atlas & Synopsis of Clinical Ophthalmology. Wills Eye Institute’, by C.J. Rapuano. Wolters Kluwer/Lippincott Williams & Wilkins, Philadelphia 2012

This book is one in a series of seven atlases covering the ophthalmic sub-specialties: cornea, retina, glaucoma, oculoplastics, neuro-ophthalmology, uveitis and paediatrics. The author of Cornea and editor of the series is Christopher Rapuano, Attending Surgeon and Director of the Cornea Service at Wills Eye Hospital in Philadelphia, Pennsylvania, USA. In the introduction to the book, Rapuano states ‘The goal of this series is to provide an up-to-date clinical overview of the major areas of ophthalmology for students, residents and practitioners in all the healthcare professions’...

Analysis of expressed sequence tags from Actinidia : Applications of a cross species EST database for gene discovery in the areas of flavor, health, color and ripening

Background Kiwifruit (Actinidia spp.) are a relatively new, but economically important crop grown in many different parts of the world. Commercial success is driven by the development of new cultivars with novel consumer traits including flavor, appearance, healthful components and convenience. To increase our understanding of the genetic diversity and gene-based control of these key traits in Actinidia, we have produced a collection of 132,577 expressed sequence tags (ESTs). Results The ESTs were derived mainly from four Actinidia species (A. chinensis, A. deliciosa, A. arguta and A. eriantha) and fell into 41,858 non redundant clusters (18,070 tentative consensus sequences and 23,788 EST singletons). Analysis of flavor and fragrance-related gene families (acyltransferases and carboxylesterases) and pathways (terpenoid biosynthesis) is presented in comparison with a chemical analysis of the compounds present in Actinidia including esters, acids, alcohols and terpenes. ESTs are identified for most genes in color pathways controlling chlorophyll degradation and carotenoid biosynthesis. In the health area, data are presented on the ESTs involved in ascorbic acid and quinic acid biosynthesis showing not only that genes for many of the steps in these pathways are represented in the database, but that genes encoding some critical steps are absent. In the convenience area, genes related to different stages of fruit softening are identified. Conclusion This large EST resource will allow researchers to undertake the tremendous challenge of understanding the molecular basis of genetic diversity in the Actinidia genus as well as provide an EST resource for comparative fruit genomics. The various bioinformatics analyses we have undertaken demonstrates the extent of coverage of ESTs for genes encoding different biochemical pathways in Actinidia.