A method for the determination of total cholesterol in serum is described. Optimum conditions are found for the isolation of the steroid free from extraneous chromogens, and a new sensitive colour reagent is introduced. The procedure is convenient for routine application, the final colour being light-stable and reasonably time-stable at room temperature. Comparisons are made with one other meth...

Habitat heterogeneity that occurs within an individual's lifetime may favour the evolution of reversible plasticity. Colour reversibility has many different functions in animals, such as thermoregulation, crypsis through background matching and social interactions. However, the mechanisms underlying reversible colour changes are yet to be thoroughly investigated. This study aims to determine th...

Computer vision systems frequently employ colour segmentation as a step of feature extraction. This is particularly crucial in an environment where important features are colour-coded, such as robot soccer. This paper describes a method for determining an appropriate colour model by measuring the compactness and separation of clusters produced by the k-means algorithm. RGB, HSV, YCbCr and CIE L...

Hierarchical neural networks require the parallel extraction of multiple features. This raises the question how a subpopulation of cells can become specific to one feature and invariant to another, while a different subpopulation becomes invariant to the first but specific to the second feature. Using a colour image sequence recorded by a camera mounted to a cat’s head, we train a population of...

Among the chief applications of the MPEG-7 visual descriptors is image indexing and retrieval. And among the colour image descriptors in the Standard having the best retrieval performance is the Colour Structure (CS) Descriptor, a descriptor that uses no more storage than an ordinary colour histogram but that substantially out-performs it. The basis of the CS Descriptor is the CS histogram, a g...

Colour is one of the most important visual attributes of food and is directly related to the perception of food quality. The interest in natural colourants, especially β-carotene that not only imparts colour but also has well-documented health benefits, has triggered the research and development of different protocols designed to entrap these hydrophobic natural molecules to improve their stabi...

We present a robust fuzzy colour processing system with automatic rule extraction and colour descriptors calibration for accurate colour object recognition and tracking in real-time. The system is anchored on the fusion of fuzzy colour contrast rules that operate on the red, green and blue channels independently and adaptively to compensate for the effects of glare, shadow, and illumination var...

Natural dyes are obtained from natural sources such as vegetable, animal or mineral matters. These generally used in coloration of textiles, food, cosmetics and drugs. This article attempts to reviews the classification according method application available dye sources, mordant its classification, different mordanting methods, extraction dyeing methods advantages disadvantages have been discus...