Variation in visual spectral tuning has evolved in concert with signal colour in some taxa, but there is limited evidence of this pattern in birds. To further investigate this possibility, we compared spectral sensitivity among bowerbird species that occupy different visual habitats and are highly diverged in plumage and decoration colour displays, which are important in mate choice and possibl...

Discriminating material changes from illumination changes is a key function of early vision. Luminance cues are ambiguous in this regard, but can be disambiguated by co-incident changes in colour and texture. Thus, colour and texture are likely to be given greater prominence than luminance for object segmentation, and better segmentation should in turn produce stronger grouping. We sought to me...

Decolourization activity of Phanerochaete chrysosporium for three synthetic dyes viz., congo red, malachite green and crystal violet and impact of additional carbon and nitrogen supply on decolourization capacity of fungus were investigated. Maximum decolourizing capacity was observed up to 15 ppm. Addition of urea as nitrogen source and glucose as carbon source significantly enhanced decolouri...

Three ammonia-producing enzymes were selected for study, namely adenosine deaminase (adenosine aminohydrolase, EC 3.5.4.4), AMP deaminase (AMP aminohydrolase, EC 3.5.4.6) and urease (urea amidohydrolase, EC 3.5.1 3). Activities were detected after each enzyme preparation was subjected to electrophoresis on both starch gel and cellulose acetate strips. Adenosine deaminase activity had been detec...

The discriminability of colours along two axes in chromaticity space has been studied by measuring the time that a normal observer requires to decide whether two colours are identical or different. By means of a multidimensional scaling program, these data were used to generate a space in which the distance between pairs of colours increases as the response time decreases. The results of this a...

Abstract Confirmed since the twelth century, Saxon community in Transylvania developed over years a rigorous powerful society, with its own lifestyle, social, economic, cultural and artistic standards. Together research historic documents, this society is now revealed by material studies of eighteenth– twentieth century objects Emil Sigerius collection, preserved ASTRA Museum, Sibiu, Romania. E...

A colour indicator for the full range of enantiomeric excess (-100%-->100% ee) is presented which is based on visual colour inspection of a liquid crystal doped with the analyte, i.e. the methyl ester of amino acid phenylglycine, providing the enantiomeric excess and allowing the assignment of the major enantiomer.