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Colloidal approach to prepare colour blends from colourants with different solubility profiles.  


Food colouring plays a vital and a determining role in the processing and the manufacturing of food products because the appearance of products is critical for attracting consumers and influencing their food choices. However, factors such as legislative restrictions, limited number of approved colourants and the processing, formulation and stability issues of the natural colourants severely limits the application of food colouring in actual product formats. Hence, finding alternatives to the currently utilised formulation practises, represents an important area of research. Here, we report a simple colloidal approach to prepare colour blends by co-incorporating colourants with contrasting aqueous solubility profiles in composite colloidal particles. Curcumin and indigocarmine were selected as water insoluble and water soluble food-grade colourants respectively and incorporated in the colloidal particles prepared from food protein-zein. Composite particles obtained by loading of curcumin and indigocarmine (at different ratios) had mean particle size ranging from 76 to 300nm. The spherical shape of the colloidal particles was confirmed using transmission electron microscopy and the colloidal dispersions were further characterised using UV-Vis and fluorescence spectroscopy. The incorporation of colourants in colloidal particles led to the generation of different shade of colour in yellow-green-blue range. The encapsulation also led to the stabilization of individual pigments against photodegradation. Such composite colloidal particles could potentially serve as an approach for developing tuneable colouring system for food and nutraceutical applications. PMID:23790940

Patel, A R; Heussen, P C M; Dorst, E; Hazekamp, J; Velikov, K P



Filling-in with colour: different modes of surface completion.  


We investigated the figural dynamics of filling-in processes in figures with more than one possible figure-ground organisation. Using a central disk and two concentric rings as well as similar stimuli consisting of three nested squares or parallel stripes, we tested for filling-in with different equiluminant colour combinations. We observed four modes of filling-in: First, in most of the cases, the inner ring assumed the colour of the central disk and outer ring (M1). Second, the central disk became filled-in with the colour of the inner ring, without any colour change on the outer ring (M2). Third, in a first step, the colour of the inner ring spread onto the central disk; then, in a second step, the colour of the outer ring spread over the whole stimulus (M3). This two step filling-in process has not been reported so far. Fourth, a mode (M4) was sometimes observed that was characterised by the central disk and outer ring assuming the colour of the inner ring. Thus, colour filling-in or colour spreading proceeded both in a centripetal (periphery to fovea) as well as a centrifugal direction. The colours red and yellow proved to be stronger inducers than blue and green. Conversely, the latter colours became filled-in more easily than the former. The filled-in colour was always that of the inducing stimulus, i.e., there was no colour mixture. This suggests a long-range, neural process underlying filling-in under these conditions. PMID:16197977

Hamburger, Kai; Prior, Helmut; Sarris, Viktor; Spillmann, Lothar



Quantitative analysis of six lignans in fruits with different colours of Schisandra chinensis by HPLC.  


A simple and rapid high-performance liquid chromatography method was utilised for the simultaneous determination of six major lignans in Schisandra chinensis with different colours continuously for the next 2 years. Six lignans were successfully separated on a C18 column at 254 nm using a gradient of acetonitrile and water. The assay was applied for analysing six lignans in the different colours of fruits of S. chinensis such as red, pink or white, and the component stability for the next 2 years was also detected. The result indicated that the total content of lignans in fruits with different colours varied remarkably, which was relatively high in red fruits, followed by white fruits and the lowest in pink fruits. Moreover, the contents of lignans in the samples of S. chinensis examined for the next 2 years changed irregularly and marginally. PMID:24650174

Sun, Dan; Li, Qian; Li, Hongbo; Li, Yanhui; Piao, Zhongyun



Chameleons communicate with complex colour changes during contests: different body regions convey different information.  


Many animals display static coloration (e.g. of feathers or fur) that can serve as a reliable sexual or social signal, but the communication function of rapidly changing colours (as in chameleons and cephalopods) is poorly understood. We used recently developed photographic and mathematical modelling tools to examine how rapid colour changes of veiled chameleons Chamaeleo calyptratus predict aggressive behaviour during male-male competitions. Males that achieved brighter stripe coloration were more likely to approach their opponent, and those that attained brighter head coloration were more likely to win fights; speed of head colour change was also an important predictor of contest outcome. This correlative study represents the first quantification of rapid colour change using organism-specific visual models and provides evidence that the rate of colour change, in addition to maximum display coloration, can be an important component of communication. Interestingly, the body and head locations of the relevant colour signals map onto the behavioural displays given during specific contest stages, with lateral displays from a distance followed by directed, head-on approaches prior to combat, suggesting that different colour change signals may evolve to communicate different information (motivation and fighting ability, respectively). PMID:24335271

Ligon, Russell A; McGraw, Kevin J



Applying colour science in colour design  

NASA Astrophysics Data System (ADS)

Although colour science has been widely used in a variety of industries over the years, it has not been fully explored in the field of product design. This paper will initially introduce the three main application fields of colour science: colour specification, colour-difference evaluation and colour appearance modelling. By integrating these advanced colour technologies together with modern colour imaging devices such as display, camera, scanner and printer, some computer systems have been recently developed to assist designers for designing colour palettes through colour selection by means of a number of widely used colour order systems, for creating harmonised colour schemes via a categorical colour system, for generating emotion colours using various colour emotional scales and for facilitating colour naming via a colour-name library. All systems are also capable of providing accurate colour representation on displays and output to different imaging devices such as printers.

Luo, Ming Ronnier



Colour stability of denture teeth submitted to different cleaning protocols and accelerated artificial aging.  


Acrylic resin is widely used for artificial teeth manufacturing due to several important characteristics; however, this material do not present acceptable colour stability over the course of time. This study evaluated the effect of different cleaning protocols and accelerated artificial aging on colour stability of denture teeth made of acrylic resin. Sixty denture teeth in dark and light shades were used, and separated according to the treatment to which they were submitted. Results demonstrated that colour stability of artificial teeth is influenced by the cleaning solution and artificial aging, being dark teeth more susceptible to colour alteration than lighter ones. PMID:24922996

Freire, T S; Aguilar, F G; Garcia, L da Fonseca Roberti; Pires-de-Souza, F de Carvalho Panzeri



Colour, phenolic content and antioxidant capacity of some fruits dehydrated by a combination of different methods.  


The objective of this study was to improve product quality of dehydrated fruits (apple, pear, papaya, mango) using combined drying techniques. This involved investigation of bioactivity, colour, and sensory assessment on colour of the dried products as well as the retention of the bio-active ingredients. The attributes of quality were compared in regard to the quality of dehydrated samples obtained from continuous heat pump (HP) drying technique. It was found that for apple, pear and mango the total colour change (?E) of samples dried using continuous heat pump (HP) or heat pump vacuum-microwave (HP/VM) methods was lower than of samples dried by other combined methods. However, for papaya, the lowest colour change exhibited by samples dried using hot air-cold air (HHC) method and the highest colour change was found for heat pump (HP) dehydrated samples. Sensory evaluation revealed that dehydrated pear with higher total colour change (?E) is more desirable because of its golden yellow appearance. In most cases the highest phenol content was found from fruits dried by HP/VM method. Judging from the quality findings on two important areas namely colour and bioactivity, it was found that combined drying method consisted of HP pre-drying followed by VM finish drying gave the best results for most dehydrated fruits studied in this work as the fruits contain first group of polyphenol compounds, which preferably requires low temperature followed by rapid drying strategy. PMID:23993562

Chong, Chien Hwa; Law, Chung Lim; Figiel, Adam; Wojdy?o, Aneta; Oziemb?owski, Maciej



Effects of different repolishing techniques on colour change of provisional prosthetic materials.  


OBJECTIVES. To investigate repolishing effect of stained provisional prosthetic materials in vitro. METHODS. Thirty two cylindrical specimens (10 x 2 mm) were prepared for each of light-polymerized composites (Revotek LC, Rx-Create), bis-acryl composites (Structur Premium, Protemp Garant3, Luxatemp Fluorescence), methyl-methacrylate (UnifastTRAD) and ethyl-methacrylate (DentalonPlus) based provisional material using a mould. The specimens were divided into 4 groups (n=8) according to different repolishing techniques. The specimens were stored for 24 hours at 37 degrees C in distilled water, and then transferred into 4 different staining agents. The colour was measured with a spectrophotometer (Vita Easyshade) before exposure and after repolishing procedures, and colour changes (DeltaE) were calculated. Statistical analysis: three-way ANOVA, Tukey HSD post-hoc test (p<0.05). RESULTS. The influence of type of provisional material, polishing procedure, food colorants and combinations of them on colour change was significant (p<0.05). After the repolishing procedures, all the specimens stored in distilled water achieved an unnoticeable colour change (DeltaE<3.7), except Dentalon Plus, Rx Create, Unifast TRAD. A similar tendency was observed in artificial food colourant solution following subsequent repolishing of the specimens. As for the red wine, all repolished specimens attained unnoticeable colour change (DeltaE<3.7), except Dentalon Plus using Rx polishing paste, Enhance polishing set or repeated glazing procedure. CONCLUSION. Repolishing was found to be an effective way to improve aesthetic appearance for provisional prosthetic materials by partially removing staining observed on the surface of the restorations. PMID:20179397

Rutkunas, Vygandas; Sabaliauskas, Vaidotas



Laser cleaning of calcareous stones: influence of laser irradiation in colour changes of different layers  

NASA Astrophysics Data System (ADS)

Experimental laser cleaning of black crusted calcareous stones, carried on to study the laser yellowing of petreous surfaces, showed different colour alterations on the exposed surface, after laser irradiation, depending not only on the incident fluence but also with the crust or stone irradiated layer.

Amaral, Sandra S.; Pires, Margarida; Carvalho, M. D.; Costa, F. M.



Escape tactics of two syntopic forms of the Lacerta perspicillata complex with different colour patterns  

Microsoft Academic Search

It has been suggested that dorsal colour patterns and defence strategies could have coevolved in reptiles, the striped species being more prone to flee compared with the spotted species that rely more on crypsis. Because of the confounding effects of phylogeny and habitat, we compared closely related forms that share the same habi- tats and predation pressures but display different

Miguel A. Carretero; Raquel Vasconcelos; Miguel Fonseca; Antigoni Kaliontzopoulou; José C. Brito; D. James Harris; Anna Perera



An Examination of Ethnic and Gender Differences in the Raven Coloured Progressive Matrices Test.  

ERIC Educational Resources Information Center

Response patterns to the Raven Coloured Progressive Matrices (CPM) were analyzed for a sample of 203 Hispanic and 254 Anglo first- through fifth-grade children from a rural school district in southern Colorado. Gender distributions were nearly equal. Gender and ethnic differences were examined within the context of determining whether the CPM…

Kluever, Raymond C.; Green, Kathy E.


Comparing soil surface roughness patterns at different colour and organic matter conditions using shadow analysis method  

NASA Astrophysics Data System (ADS)

The method based on the shadow analysis has shown to be one of the most convenient techniques to characterize SSR in the field when used in arid and semi-arid regions. However, the technique has not been proved with soils having more than 3% of organic matter and soil with very dark colours. In order to proof that the technique is able to function at field trials with soils richer in organic matter and with different colours, the project compared SSR resulting in 5 different types of soils after passing chisel. The main variation amongst the soils was the colour, brown soils, grey pale soils and yellow soils and the organic matter associated, 1 to 6%. All the plots measured 1m2 and were used for crop production. For each site 6 plots were considered and all the data was captured during summer time to avoid the influence of rain. The SSR obtained varied from 44 to 62% showing that the results were not significantly related to the darkness of colour and the content of organic matter. The variations were strongly related to the amount of clay found on different soils. This difference could be introduced by the difficulty in some cases to pass the chisel when soil is too dried since the acquisition of field data was done after chisel tool was passed on different sites. The parameters demonstrated that the method can be used to study the influence of wind and water erosion on soil surface at field conditions with independence of colour and organic matter properties.

García Moreno, R.; Diaz Alvarez, M. C.; Saa Requejo, A.; Guerrero López, F.



Assessment of different colour parameters for discriminating potential suspended sediment sources and provenance: A multi-scale study in Luxembourg  

NASA Astrophysics Data System (ADS)

Sediment colour has recently been used successfully to estimate suspended sediment sources in small catchments using the fingerprinting approach. The methodology offers opportunity for further research since it provides a rapid and cheap means for investigating sediment sources. However, the colour-based fingerprinting approach has not yet been tested in medium and large catchments. This paper aims to test whether colour parameters are capable of discriminating sediment sources in a nested system of seven sub-catchments ranging from 0.7 to 247 km 2 of the Attert River catchment, NW Luxembourg. Time-integrated suspended sediment samples and samples of potential sediment sources (land-use types and channel banks) were collected in all catchments. Sediment colour was then computed from diffuse reflectance spectrometry measurements (ASD FieldSpec-II spectrometer, 0.4-2.5 µm) taken over the visible wavelength range. Twenty-four colour parameters were derived from several colour space models (CIE xyY, CIE XYZ, RGB, Munsell HVC, Helmholtz chromaticity, CIELUV and CIELAB) and their ability to discriminate potential suspended sediment sources and provenance was evaluated and compared. Results demonstrated that time-integrated suspended sediment samples collected in the study catchments had statistically different colour values. Moreover, these values always represented a mixture of the colour values measured on potential suspended sediment sources in the catchment. Inter-source colour contrasts (land-use types and channel banks) were observed in all catchments (Kruskal-Wallis H-test). However, although colour is able to distinguish potential sediment sources in small catchments, the level of source discrimination decreases as the catchment size increases, probably due to heterogeneous geology and pedology, intra-source variability and to source overlap. Nevertheless, in the studied medium-sized catchments (ranging from 19.4 to 247 km 2), colour could differentiate between topsoil and sub-surface (i.e. channel bank) material and/or up to three sources types. No single colour model had discrimination power across catchments, instead in each catchment a different combination of colour parameters gathered from different colour space models produced optimal discrimination of potential sediment sources. Furthermore, a colour-based fingerprinting approach did not possess potential for integrating spatial provenance and source type information because colour parameters could not discriminate between contrasting geological sub-areas. In summary, although colour parameters were not capable of discriminating the range of land-use type and channel banks as potential suspended sediment sources in medium-sized catchments, they afford substantial information and could be integrated into the classical fingerprinting approach together with other constituents (e.g. geochemistry, radionuclides and/or organic compounds).

Martínez-Carreras, Núria; Krein, Andreas; Gallart, Francesc; Iffly, Jean F.; Pfister, Laurent; Hoffmann, Lucien; Owens, Philip N.



Cognition factors in colour identification of colour blind people  

Microsoft Academic Search

Cognition of colour blind people differs significantly from colour normal observers especially in their colour identification and discrimination. Dichromats lacking one of the three cone photoreceptor types identify less colours and have a general confusion determining colour terms. Our research was aimed to reveal several aspects of their colour cognition with newly developed methodologies and diagnostic equipment. Among other features

Gyorgy Abraham; Balazs V. Nagy



Structure of organic matter in conodonts with different colour alteration indexes  

Microsoft Academic Search

Devonian conodont samples from the Beechwood Member of the North Vernon Limestone, IN, USA and Garra Formation Wellington, NSW, Australia with Colour Alteration Index (CAI) values of 2 and 4, respectively, were analysed using X-ray photoelectron spectroscopy (XPS), pyrolysis gas chromatography mass spectrometry (py-GC\\/MS) and Fourier transform infrared emission spectroscopy (FTIRES). The results show the organic matter is different for

C. P Marshall; H. R Rose; G. S. H Lee; G. L Mar; M. A Wilson



Different roles of natural and sexual selection on senescence of plumage colour in the barn swallow  

Microsoft Academic Search

Summary 1. Colour may show effects of senescence because the pigment or structures involved in production of colouration deteriorate with age. 2. We tested this hypothesis by investigating age-related changes in plumage colour for two feather tracts coloured by eumelanin or pheomelanin in a longitudinal study of a cohort of barn swallows Hirundo rustica that reached very old age (at

Ismael Galván; Anders Pape Møller



Discrete colour polymorphism in the tawny dragon lizard (Ctenophorus decresii) and differences in signal conspicuousness among morphs.  


Intraspecific colour variation is common in nature and can vary from the coexistence of discrete colour variants in polymorphic species to continuous variation. Whether coloration is continuous or discrete is often ambiguous and many species exhibit a combination of the two. The nature of the variation (discrete or continuous) has implications for both the genetic basis of the colour variation and the evolutionary processes generating and maintaining it. Consequently, it is important to qualify the existence of discrete morphs, particularly in relation to the animal's visual system. In this study, we quantified male throat colour variation in Ctenophorus decresii tawny dragon lizard and tested for morphological and ecological correlates of the colour variants. We confirmed that discrete throat colour morphs can be defined based on colour and pattern analyses independent of the human visual system. We also found that the colour variants differed in their conspicuousness from the background, to the lizard's visual system, which has implications for signalling. However, the morphs did not differ in morphology or microhabitat use, which suggests that these characteristics are not involved in the evolutionary maintenance of the polymorphism. PMID:23495663

Teasdale, L C; Stevens, M; Stuart-Fox, D



Effects of Xe Gas Content and Total Gas Pressure on the Discharge Characteristics of Colour Plasma Display Panels  

NASA Astrophysics Data System (ADS)

The effects of the Xe gas content and total gas pressure on the discharge characteristics of colour plasma display panels including the sustaining voltage margin, white-field chromaticity, discharge time lag (DTL), discharge current peak, and full-width-at-half-maximum (FWHM) of the discharge current pulse, are experimentally studied. The results indicate that as the Xe gas content in the He-Ne-Xe gas mixture or total pressure increases, the sustaining voltage margin increases, the white-field chromaticity improves, and the discharge current peak has a maximum value, while DTL and FWHM have a minimum value. The mean electron energy in the gas mixture discharge is also calculated through a numerical solution of Boltzmann equation. The experimental results are explained from a view of the mean electron energy variations with the Xe gas content and total gas pressure.

Hu, Wenbo; Han, Mengju; Liang, Zhihu



Colour effects of co-pigmentation of anthocyanin revisited—3. A further description using CIELAB differences and assessment of matched colours using the CMC model  

Microsoft Academic Search

Extensive colour difference calculations (CIELAB and CMC models for CIE D65\\/10°, Ill.\\/Obs.) were applied to the colorimetric coordinates previously gathered on 224 pure or co-pigmented (by rutin) solutions of cyanin at pH between 2.5 and 5.5. CIELAB coordinates additionally recorded on acidic (0.1N HCl) methanolic and aqueous cyanin solutions (10?5 M?2.5×10?3 M) showed the considerable hue gamut covered by each

Jean-François Gonnet



Effect of colouring green stage zirconia on the adhesion of veneering ceramics with different thermal expansion coefficients  

PubMed Central

This study evaluated the adhesion of zirconia core ceramics with their corresponding veneering ceramics, having different thermal expansion coefficients (TECs), when zirconia ceramics were coloured at green stage. Zirconia blocks (N=240; 6 mm×7 mm×7 mm) were manufactured from two materials namely, ICE Zirconia (Group 1) and Prettau Zirconia (Group 2). In their green stage, they were randomly divided into two groups. Half of the specimens were coloured with colouring liquid (shade A2). Three different veneering ceramics with different TEC (ICE Ceramic, GC Initial Zr and IPS e.max Ceram) were fired on both coloured and non-coloured zirconia cores. Specimens of high noble alloys (Esteticor Plus) veneered with ceramic (VM 13) (n=16) acted as the control group. Core–veneer interface of the specimens were subjected to shear force in the Universal Testing Machine (0.5 mm?min?1). Neither the zirconia core material (P=0.318) nor colouring (P=0.188) significantly affected the results (three-way analysis of variance, Tukey's test). But the results were significantly affected by the veneering ceramic (P=0.000). Control group exhibited significantly higher mean bond strength values (45.7±8) MPa than all other tested groups ((27.1±4.1)?(39.7±4.7) and (27.4±5.6)?(35.9±4.7) MPa with and without colouring, respectively) (P<0.001). While in zirconia–veneer test groups, predominantly mixed type of failures were observed with the veneering ceramic covering <1/3 of the substrate surface, in the metal–ceramic group, veneering ceramic was left adhered >1/3 of the metal surface. Colouring zirconia did not impair adhesion of veneering ceramic, but veneering ceramic had a significant influence on the core–veneer adhesion. Metal–ceramic adhesion was more reliable than all zirconia–veneer ceramics tested.

Aktas, Guliz; Sahin, Erdal; Vallittu, Pekka; Ozcan, Mutlu; Lassila, Lippo



Anti-oxidative analysis, and identification and quantification of anthocyanin pigments in different coloured rice.  


Anthocyanin pigments in coloured rice cultivars were isolated and identified using high-performance liquid chromatography techniques. Two black rice cultivars (Asamurasaki, Okunomurasaki) contained three major anthocyanins: cyanidin-3-glucoside, peonidin-3-glucoside and malvidin. Chinakuromai (black) rice additionally contained a fourth anthocyanin, petunidin-3-glucoside. Four red rice cultivars contained only malvidin. The total anthocyanin content varied greatly among black rice cultivars (79.5-473.7 mg/100g), but was lower in red rice (7.9-34.4 mg/100g). Total phenolic content was similar between red (460.32-725.69 mg/100g) and black (417.11-687.24 mg/100g) rice. The oxygen radical absorbing capacity was ranked as follows: red (69.91-130.32 ?mol Trolox/g)>black (55.49-64.85 ?mol Trolox/g)>green (35.32 ?mol Trolox/g)>white (21.81 ?mol Trolox/g) rice. The antioxidant capacity resulted mainly from the seed capsule, not the endosperm. The anthocyanin pigments contributed little to the total antioxidant capacity of red (0.03-0.1%) and black (0.5-2.5%) rice cultivars. Hence, the antioxidant capacity is derived mainly from other phenolic compounds. PMID:22980872

Chen, Xiao Qiong; Nagao, Norio; Itani, Tomio; Irifune, Kohei



Measurement of surface temperature and emissivity of different materials by two-colour pyrometry  

NASA Astrophysics Data System (ADS)

An experimental investigation is performed to substantiate the capability of a charge coupled device camera to measure local temperature and emissivity of different materials heated to temperatures above 500 °C by two-colour pyrometric technique using colorimetric method. Materials investigated are Inconel 718 with pyromark (high temperature paint), Inconel 718, stainless steel SS 304 and SS 316. Centerline temperature and emissivity distribution is obtained for target plates maintained at constant temperature by AC heating while complete temperature and emissivity distribution is provided for plates heated by flame impingement. The obtained results are compared with a calibrated infrared camera and thermocouples and the temperature distribution is found to be in close agreement. These results pertain to partially oxidized metal alloys covered in this study. Deviation in the measurement of emissivity can be attributed to its dependence on wavelength range, oxidation, and sensitivity of the image detector.

Raj, Vinay C.; Prabhu, S. V.



Measurement of surface temperature and emissivity of different materials by two-colour pyrometry.  


An experimental investigation is performed to substantiate the capability of a charge coupled device camera to measure local temperature and emissivity of different materials heated to temperatures above 500 °C by two-colour pyrometric technique using colorimetric method. Materials investigated are Inconel 718 with pyromark (high temperature paint), Inconel 718, stainless steel SS 304 and SS 316. Centerline temperature and emissivity distribution is obtained for target plates maintained at constant temperature by AC heating while complete temperature and emissivity distribution is provided for plates heated by flame impingement. The obtained results are compared with a calibrated infrared camera and thermocouples and the temperature distribution is found to be in close agreement. These results pertain to partially oxidized metal alloys covered in this study. Deviation in the measurement of emissivity can be attributed to its dependence on wavelength range, oxidation, and sensitivity of the image detector. PMID:24387454

Raj, Vinay C; Prabhu, S V



Effects of memory colour on colour constancy for unknown coloured objects  

PubMed Central

The perception of an object's colour remains constant despite large variations in the chromaticity of the illumination—colour constancy. Hering suggested that memory colours, the typical colours of objects, could help in estimating the illuminant's colour and therefore be an important factor in establishing colour constancy. Here we test whether the presence of objects with diagnostical colours (fruits, vegetables, etc) within a scene influence colour constancy for unknown coloured objects in the scene. Subjects matched one of four Munsell papers placed in a scene illuminated under either a reddish or a greenish lamp with the Munsell book of colour illuminated by a neutral lamp. The Munsell papers were embedded in four different scenes—one scene containing diagnostically coloured objects, one scene containing incongruent coloured objects, a third scene with geometrical objects of the same colour as the diagnostically coloured objects, and one scene containing non-diagnostically coloured objects (eg, a yellow coffee mug). All objects were placed against a black background. Colour constancy was on average significantly higher for the scene containing the diagnostically coloured objects compared with the other scenes tested. We conclude that the colours of familiar objects help in obtaining colour constancy for unknown objects.

Granzier, Jeroen J M; Gegenfurtner, Karl R



Genetics of eye colours in different rural populations on the Silk Road.  


Eye colour is a highly transmissible and discernible trait in humans. A genome-wide association scan for variants associated to eye pigmentation was carried out on a large group of individuals coming from the Silk Road. Significant associations were detected not only with HERC2 (P-value=4.99 × 10(-37)) and OCA2 (P-value=4.51 × 10(-9)) genes but also with CTNNA2 gene (P-value=4.06 × 10(-8)). Moreover, the multifactor dimensionality reduction analysis clearly showed the effect of HERC2 haplotype over OCA2 mostly associated with SNP, thus enabling a highly accurate eye-colour prediction. Finally, the regression tree analysis showed that individuals carrying a given combination of haplotypes have a significant probability to show a blue or green/grey iris colour as compared with brown, with a gradient from west to east. PMID:23486544

Ulivi, Sheila; Mezzavilla, Massimo; Gasparini, Paolo



Missense and nonsense mutations in melanocortin 1 receptor (MC1R) gene of different goat breeds: association with red and black coat colour phenotypes but with unexpected evidences  

Microsoft Academic Search

BACKGROUND: Agouti and Extension loci control the relative amount of eumelanin and pheomelanin production in melanocytes that, in turn, affects pigmentation of skin and hair. The Extension locus encodes the melanocortin 1 receptor (MC1R) whose permanent activation, caused by functional mutations, results in black coat colour, whereas other inactivating mutations cause red coat colour in different mammals. RESULTS: The whole

Luca Fontanesi; Francesca Beretti; Valentina Riggio; Stefania Dall'Olio; Elena Gómez González; Raffaella Finocchiaro; Roberta Davoli; Vincenzo Russo; Baldassare Portolano



Cadmium colours: composition and properties  

NASA Astrophysics Data System (ADS)

The composition and the properties of cadmium aquarelle colours are discussed. The examined colours were 24 different aquarelle cadmium colours from six different manufacturers. The colours ranged from light, bright yellows to dark, deep-red tones. The aim of this research was to find out if the pigments contain cadmium salts: sulphides and/or selenides. This information will help in choosing watercolours in conservation processes. Today, aquarelle colours not containing cadmium pigments are being sold as cadmium colours; thus their properties might be different from actual cadmium colours. The aim of the research was to verify that the colour samples contained cadmium pigments and to estimate their compositions and ageing properties. Element analyses were performed from colour samples using micro-chemical tests and X-ray fluorescence measurements. Thin-layer chromatography was used for analysing gum Arabic as a possible binding medium in the chosen colour samples. Through ageing tests, the resistance of the colour samples to the exposure to light, heat and humidity was studied. Visible-light spectroscopy was used in determining the hues and hue changes of the aquarelle colour samples. The spectrophotometer used the CIE L*a*b* tone colour measuring system. From the colour measurements the changes in the lightness/darkness, the redness, the yellowness and the saturation of the samples were examined.

Paulus, J.; Knuutinen, U.


Shelf-life and colour change kinetics of Aloe vera gel powder under accelerated storage in three different packaging materials.  


Aloe vera gel powder was produced through dehumidified air drying of Aloe vere gel at optimized conditions of temperature, relative humidity and air velocity of 64 °C, 18% and 0.8 m.s(-1), respectively. The powder was packed in three different packaging materials viz., laminated aluminum foil (AF), biaxially oriented polypropylene (BOPP) and polypropylene (PP). The shelf-life of the powder was predicted on the basis of free flowness of product under accelerated storage condition (38?±?1 °C, 90?±?1% relative humidity) and was calculated to be 33.87, 42.58 and 51.05 days in BOPP, PP and AF, respectively. The storage stability of powder in terms of colour change was studied. The magnitude of colour change of Aloe vera gel powder during storage suggests that AF was better than BOPP and PP. The colour change of powder during storage followed first order reaction kinetics with a rate constant of 0.0444 per day for AF, 0.075 per day for BOPP and 0.0498 per day for PP. PMID:24425977

Ramachandra, C T; Rao, P Srinivasa



Why birds eat colourful grit: colour preferences revealed by the colour of gizzard stones.  


Colour preferences from sexual or social contexts are assumed to have arisen owing to preferences for specific kinds of food, representing a sensory bias, but once colour preferences have evolved in a sexual context, they may also be expressed during foraging. We tested whether preferences for specific body colours (i.e. plumage and soft parts) were related to colour preferences for grit ingested by birds. Birds eat grit to facilitate break down of food by the gizzard, and this function is independent of the colour of grit, but depends on the physical properties of stones. Bird species were significantly consistent in colour of grit, and grit of different colours varied in prevalence among species, even when analyses were restricted to a sample from a single locality. There were positive correlations between presence of lilac and red grit in the gizzard and presence of sexually dichromatic lilac and red colour on the body. There was a positive correlation between red grit colour and red sexually monochromatic body colour. Bird species with many different sexual colours, but not sexually monochromatic colours on their body had many different colours of grit. Males had more lilac and red grit than females, with this effect differing among species, whereas that was not the case for grit of other colours. These findings are consistent with the sensory bias hypothesis that birds express preferences for grit of specific colours and a high diversity of colours related to sexual colouration of the body, even when the colour of such grit is only visible to the individual at the moment of ingestion. PMID:20050966

Møller, A P; Erritzøe, J



Colour contribution to children's wayfinding in school environments  

NASA Astrophysics Data System (ADS)

The purpose of this study was to explore the contribution of colour to children's wayfinding ability in school environments and to examine the differences between colours in terms of their remembrance and usability in route learning process. The experiment was conducted with three different sample groups for each of three experiment sets differentiated by their colour arrangement. The participants totalled 100 primary school children aged seven and eight years old. The study was conducted in four phases. In the first phase, the participants were tested for familiarity with the experiment site and also for colour vision deficiencies by using Ishihara's tests for colour-blindness. In the second phase, they were escorted on the experiment route by the tester one by one, from one starting point to one end point and were asked to lead the tester to the end point by the same route. In the third phase, they were asked to describe verbally the route. In the final phase, they were asked to remember the specific colours at their correct locations. It was found that colour has a significant effect on children's wayfinding performances in school environments. However, there were no differences between different colours in terms of their remembrances in route finding tasks. In addition, the correct identifications of specific colours and landmarks were dependent on their specific locations. Contrary to the literature, gender differences were not found to be significant in the accuracy of route learning performances.

Helvac?o?lu, Elif; Olguntürk, Nilgün



Shape and colour measurement of colourful objects by fringe projection  

NASA Astrophysics Data System (ADS)

In this paper, we present a novel method to measure shape and colour information of a colourful object by projecting separate red, green and blue colour fringe patterns onto the object surface. With regard to the object surface's colour, the modulation at each pixel position in the three colour channels has different values. For example, when projecting blue fringe patterns onto a red point, the corresponding pixel has too low a fringe modulation to accurately calculate the phase (shape) information; but with red fringe patterns a high fringe modulation is obtained. Therefore, phase information of the red point can be calculated by projecting red fringe patterns. For each object point, by comparing the modulation values from the three colour channels, it is possible to choose the channel having maximum modulation, and hence phase information can be reliably obtained by the phase-shifting algorithm. The fringe order information is obtained by using the optimum three-frequency selection method, so there is a maximum reliability in determining the fringe order and the 3-D shape of an object with step or large slopes on the surface. Since three colour channels are used, colour information of the object surface can be extracted with high dynamic range from the same fringe patterns. Chromatic aberration between colour channels is unavoidable and can be eliminated by a software-based method. Using the recently developed colour fringe projection system, separate colour fringe patterns are projected onto a mug having different colour patterns, a colourful box and plate, and a colour checker card to test the proposed method. The results show the range of colours that can be measured and that shape and colour information of colourful objects can be reliably obtained.

Zhang, Zonghua; Towers, Catherine E.; Towers, David P.



Multi-camera colour tracking  

Microsoft Academic Search

We propose a colour tracker for use in visual surveillance. The tracker is part of a framework designed to monitor a dynamic scene with more than one camera. Colour tracking complements spatial tracking: it can also be used over large temporal intervals, and between spatially uncalibrated cameras. The colour distributions from objects are modelled, and measures of difference between them

J. Orwell; P. Remagnino; G. A. Jones



Colour Lovers  

NSDL National Science Digital Library

The endless hues and shades of colors fascinate many persons, including interior-designers, fashionistas, and those who study the workings of the human eye. This particular site is "a place to view, rate and review some lovely colours & palettes." The site contains a number of user forums where people may gather around the electronic glow of the screen to discuss and debate the merits of different colors, along with a place for users to submit their own fanciful and innovative colors. On the right-hand side of the home page, visitors can browse through the top-rated colors, newly added colors, and new palettes. Many of the colors have rather curious names, such as "wegobysundawn" and "victory or ignorance." Of course, there is space provided for visitors to give their own opinions on each color or palette. Overall, a compelling site, and one that will delight those with a penchant for the uses of color.


Minimalist surface-colour matching.  


Some theories of surface-colour perception assume that observers estimate the illuminant on a scene so that its effects can be discounted. A critical test of this interpretation of colour constancy is whether surface-colour matching is worse when the number of surfaces in a scene is so small that any illuminant estimate is unreliable. In the experiment reported here, observers made asymmetric colour matches between pairs of simultaneously presented Mondrian-like patterns under different daylights. The patterns had either 49 surfaces or a minimal 2 surfaces. No significant effect of number was found, suggesting that illuminant estimates are unnecessary for surface-colour matching. PMID:16178156

Amano, Kinjiro; Foster, David H; Nascimento, Sérgio M C



Minimalist surface-colour matching  

PubMed Central

Some theories of surface-colour perception assume that observers estimate the illuminant on a scene so that its effects can be discounted. A critical test of this interpretation of colour constancy is whether surface-colour matching is worse when the number of surfaces in a scene is so small that any illuminant estimate is unreliable. In the experiment reported here, observers made asymmetric colour matches between pairs of simultaneously presented Mondrian-like patterns under different daylights. The patterns had either 49 surfaces or a minimal 2 surfaces. No significant effect of number was found, suggesting that illuminant estimates are unnecessary for surface-colour matching.

Amano, Kinjiro; Foster, David H.; Nascimento, Sergio M C



Spatial distribution pattern analysis of Dof1 transcription factor in different tissues of three Eleusine coracana genotypes differing in their grain colour, yield and photosynthetic efficiency.  


In the present study Dof1 gene of finger millet was cloned and sequenced. In silico analysis reveals 61% identity with the Sorghum bicolor and 57% identity with the Oryza sativa Dof1 sequence. A comparative analysis of gene sequences from different crops and three finger millet genotypes {Brown (PRM-1), Golden (PRM-701) and White (PRM-801)} differing in grain colour, yield and photosynthetic efficiency showed a high degree of sequence identity of Dof1 sequence gene ranging from 22 to 70% as evident from distance matrix of the built phylogenetic tree showing two major clusters. A total of five conserved motifs were observed in Dof1 sequences of different cereals. Motif 1 with multilevel consensus sequence CKNCRRYWTKGGAMRNVPVG contains zinc finger Dof domain. Motif 3 and motif 5 contains protein kinase phosphorylation site. Motif 2 contains Dof domain and zinc finger N-glycosylation site while motif 4 is involved in Zinc finger type profiling. Further, we studied the spatial distribution of Dof1 gene in three vegetative tissues (root, stem and flag leaf) as well as four stages of developing spikes (S1, S2, S3 and S4) of the three finger millet genotypes using qualitative and quantitative PCR based approaches. Physiological parameters (plant height, leaf area, chlorophyll content, SPAD value and photosynthetic efficiency) at the time of flowering was found to be highest in white (PRM-801) genotype followed by golden (PRM-701) and brown (PRM-1) genotype. Semi-quantitative RT-PCR and quantitative real-time PCR analysis revealed that the expression of Dof1 is highest in leaves and lowest in roots, which suggests its role in regulation of photosynthesis-related genes and carbon skeleton synthesis. Also at grain maturity stage, expression of Dof1 was higher in white (PRM-801) genotype followed by golden (PRM-701) and brown (PRM-1) genotype. The result is suggestive of Dof1 role in the accumulation of grain protein and yield attribute through regulation of key enzymes involved in source to sink relationship during grain filling stage. PMID:21643752

Gupta, Nidhi; Gupta, Atul Kumar; Kumar, Anil



Tocopherols and total phenolics in 10 different nut types  

Microsoft Academic Search

The study was conducted to assess the content of tocopherols (?-, ?-, ?- and ?-) and carotenoids (?- and ?-carotene, zeaxanthin, lutein, cryptoxanthin and lycopene) in the unsaponifiable matter as well as the amount of total phenols of 10 different types of nuts. Tocopherols and carotenoids were analysed with HPLC, total phenols photometrically. The mean value of ?-tocopherol equivalents ranged

Margit Kornsteiner; Karl-Heinz Wagner; Ibrahim Elmadfa



Colour detection thresholds in faces and colour patches.  


Human facial skin colour reflects individuals' underlying health (Stephen et al 2011 Evolution & Human Behavior 32 216-227); and enhanced facial skin CIELab b* (yellowness), a* (redness), and L* (lightness) are perceived as healthy (also Stephen et al 2009a International Journal of Primatology 30 845-857). Here, we examine Malaysian Chinese participants' detection thresholds for CIELab L* (lightness), a* (redness), and b* (yellowness) colour changes in Asian, African, and Caucasian faces and skin coloured patches. Twelve face photos and three skin coloured patches were transformed to produce four pairs of images of each individual face and colour patch with different amounts of red, yellow, or lightness, from very subtle (deltaE = 1.2) to quite large differences (deltaE = 9.6). Participants were asked to decide which of sequentially displayed, paired same-face images or colour patches were lighter, redder, or yellower. Changes in facial redness, followed by changes in yellowness, were more easily discriminated than changes in luminance. However, visual sensitivity was not greater for redness and yellowness in nonface stimuli, suggesting red facial skin colour special salience. Participants were also significantly better at recognizing colour differences in own-race (Asian) and Caucasian faces than in African faces, suggesting the existence of cross-race effect in discriminating facial colours. Humans' colour vision may have been selected for skin colour signalling (Changizi et al 2006 Biology Letters 2 217-221), enabling individuals to perceive subtle changes in skin colour, reflecting health and emotional status. PMID:24344549

Tan, Kok Wei; Stephen, Ian D



Immediate colour constancy.  


Colour constancy is traditionally interpreted as the stable appearance of the colour of a surface despite changes in the spectral composition of the illumination. When colour constancy has been assessed quantitatively, however, by observers making matches between surfaces illuminated by different sources, its completeness has been found to be poor. An alternative operational approach to colour constancy may be taken which concentrates instead on detecting the underlying chromatic relationship between the parts of a surface under changes in the illuminant. Experimentally the observer's task was to determine whether a change in the appearance of a surface was due to a change in its reflecting properties or to a change in the incident light. Observers viewed computer simulations of a row of three Mondrian patterns of Munsell chips. The centre pattern was a reference pattern illuminated by a simulated, spatially uniform daylight; one of the outer patterns was identical but illuminated by a different daylight; and the other outer pattern was equivalent but not obtainable from the centre pattern by such a change in illuminant. Different patterns and different shifts in daylight were generated in each experimental trial. The task of the observer was to identify which of the outer patterns was the result of an illuminant change. Observers made reliable discriminations of the patterns with displays of durations from several seconds to less than 200 ms, and, for one observer, with displays of 1 ms. By these measures, human observers appear capable of colour constancy that is extremely rapid, and probably preattentive in origin. PMID:1408163

Foster, D H; Craven, B J; Sale, E R



Colour Sensation  

Microsoft Academic Search

IN NATURE of July 15 there is given an abstract of a paper by Dr. F. W. Edridge-Green in which he gives reasons for supposing that the sensation produced by spectral yellow is a simple sensation, and not a compound of red and green, as supposed by the Young-Helmholtz theory. In 1872 I read a paper on colour sensation before

John Aitken



Growth of chrysanthemum under coloured plastic films with different light qualities and quantities  

Microsoft Academic Search

Several spectral filters were tested on Dendranthema×grandiflorum `White Reagan' (Chrysanthemum morifolium), as an alternative for chemical growth regulators. Three blue polyethylene (PE) films and one vaporised interference film were compared to four neutral filters with corresponding PPFD transmittances (differing from 25% to 73%). The blue PE films had blue:red ratios (B:R) from 6.2 to 85.5 with increasing pigment concentration, and

E Oyaert; E Volckaert; P. C Debergh



Chemical oxygen demand, total organic carbon and colour reduction in slaughterhouse wastewater by unmodified and iron-modified clinoptilolite-rich tuff.  


In this study, reduction of chemical oxygen demand (COD), colour, and total organic carbon in effluents from a slaughterhouse in central Mexico was performed using clinoptilolite-rich tuff. The experimental parameters considered were initial concentration of the adsorbate, pH, adsorbent dosage, and contact time. Surface morphology of the materials was tested by using scanning electron microscopy. Specific surface area was analysed by using Brunauer-Emmett-Teller (BET) and phase composition was analysed by using X-ray diffraction. The experimental adsorption data were fitted to the first- and pseudo-second-order kinetic models. The highest COD removal was observed in slightly acidic pH conditions. The maximum reduction efficiency of COD was accomplished with unmodified clinoptilolite-rich tuff at a contact time of 1440 min. In these conditions, the adsorbent was efficient for treating wastewater from a slaughterhouse. Moreover, after several regeneration cycles with Fenton reagent or hydrogen peroxide, the regenerated zeolite with H2O2 (3%) showed the best reduction efficiencies. PMID:24701954

Torres-Pérez, J; Solache-Ríos, M; Martínez-Miranda, V



Complementary Colours for a Physicist  

ERIC Educational Resources Information Center

This paper reports on a simple experiment which enables splitting incident light into two different modes, each having a colour exactly complementary to the other. A brief historical development of colour theories and differences in a physicist's point of view with respect to an artist's one is discussed. An experimental system for producing…

Babic, Vitomir; Cepic, Mojca



Correlation between ethylene emission and skin colour changes during papaya (Carica papaya L.) fruit ripening  

Microsoft Academic Search

The skin colour changes and ethylene emission rates were monitored during papaya (C. papaya L.) fruit ripening. Two groups of papaya (`Formosa' and `Solo') were applied in this study. The total colour difference was used as measured parameter and the corresponding half time of its saturation was used as correlation parameter. A high correlation factor between the saturation half time

M. G. da Silva; J. G. Oliveira; A. P. Vitoria; S. F. Corrêa; M. G. Pereira; E. Campostrini; E. O. Santos; A. Cavalli; H. Vargas



Three cortical stages of colour processing in the human brain.  


We used the technique of functional magnetic resonance imaging to chart the colour pathways in the human brain beyond V4. We asked subjects to view objects that were dressed in natural and unnatural colours as well as their achromatic counterparts and compared the activity produced in the brain by each condition. The results showed that both naturally and unnaturally coloured objects activate a pathway extending from V1 to V4, though not overlapping totally the activity produced by viewing abstract coloured Mondrian scenes. Normally coloured objects activated, in addition, more anterior parts of the fusiform gyrus, the hippocampus and the ventrolateral frontal cortex. Abnormally coloured objects, by contrast, activated the dorsolateral frontal cortex. A study of the cortical covariation produced by these activations revealed that activity in large parts of the occipital lobe covaried with each. These results, considered against the background of previous physiological and clinical studies, allow us to discern three broad cortical stages of colour processing in the human brain. The first is based on V1 and possibly V2 and is concerned mainly with registering the presence and intensity of different wavelengths, and with wavelength differencing. The second stage is based on V4 and is concerned with automatic colour constancy operations, without regard to memory, judgement and learning. The third stage, based on the inferior temporal and frontal cortex, is more concerned with object colours. The results we report, as well as the schema that we suggest, also allow us to reconcile the computational theory of Land, implemented without regard to cognitive factors such as memory and learning, and the cognitive systems of Helmholtz and Hering, which view such factors as critical in the determination of colours. PMID:9762956

Zeki, S; Marini, L



Genetics of Castes and Tribes of India: A Review of Population Differences in Red and Green Colour Vision Deficiency in India  

Microsoft Academic Search

KEYWORDS Colour vision defect; X-linked trait; population differences; relaxed natural selection ABSTRACT The discipline of Biological Anthropology (or Human Biology) incorporates study of biology and environmental factors, as well as the forces of micro-evolution leading to macro-evolution, which ultimately influences the structure of human populations. In the present paper and attempt has been made to study the distribution differences in

M. K. Bhasin


Factorial Analysis of Colour Vision  

Microsoft Academic Search

HOUSTOUN1 has pointed out that a three-colour theory, such as that of Young and Helmholtz, inevitably leads to mathematical contradictions. It is well known in addition that a theory in which there are only three primary sensitivities, such as red, green and blue, becomes unsatisfactory when the many different forms of defective colour vision are studied in detail. Piéron2 has

R. W. Pickford



A comparison of two different instruments for measuring venison CIELAB values and colour assessment by a trained panel  

Microsoft Academic Search

Venison colour was measured with a Minolta Chroma Meter CR200b portable filter colorimeter to give CIE (1976) Lab (CIELAB) values the results were compared with those obtained with a Hunter LabScan 6000 scanning reflectance spectrocolorimeter and a sensory evaluation panel. The values obtained depended on the instrument used, but the variations from one instrument to another were systematic, enabling the

J. M. Stevenson; I. L. Weatherall; R. P. Litilejohn; D. L. Seman



Significance of early postmortem temperature and pH decline on colour characteristics of pork loin from different crossbreeds  

Microsoft Academic Search

The significance of early postmortem (pm) temperature and pH decline and the level of the muscle metabolites creatine phosphate (CP) and adenosine triphosphate (ATP) on the colour of porcine M. longissimus dorsi was studied in a factorially designed experiment. Two stress levels peri mortem (minimal stress vs treadmill exercise and electrical stunning of the pigs) and four genotypes (Duroc boars

Gunilla Lindahl; Poul Henckel; Anders H. Karlsson; Henrik J. Andersen



The colours of cloaks  

Microsoft Academic Search

We present a survey of results from various research groups under the unifying viewpoint of transformational physics, which has been recently introduced for the design of metamaterials in optics and acoustics. We illustrate the versatility of underlying geometric transforms in order to bridge wave phenomena (the different 'colours' of waves) ranging from transverse electric waves, to linear surface water waves

Sébastien Guenneau; Ross C. McPhedran; Stefan Enoch; Alexander B. Movchan; Mohamed Farhat; Nicolae-Alexandru P. Nicorovici



Microstructure and bioaccessibility of different carotenoid species as affected by high pressure homogenisation: a case study on differently coloured tomatoes.  


The effect of high pressure homogenisation (HPH) on structure (Bostwick consistency, particle size distribution and microstructure) and carotenoid in vitro bioaccessibility of different tomato pulps was investigated. HPH decreased tomato particle size due to matrix disruption and increased product consistency, probably due to the formation of a fibre network. Homogenisation also resulted in a decrease of in vitro bioaccessibility of lycopene, ?-carotene, and lutein. Such decrease was attributed to the structuring effect of HPH. An inverse relation between tomato consistency and carotenoid in vitro bioaccessibility was found. This dependency was affected by carotenoid species and its localisation within the matrix. It could be observed that one matrix (e.g. (homogenised) red tomato pulp) can contain carotenoids with a very low bioaccessibility (lycopene) as well as carotenoids with a very high bioaccessibility (lutein), indicating that carotenoid bioaccessibility is not solely dependent on the matrix. PMID:23993590

Panozzo, Agnese; Lemmens, Lien; Van Loey, Ann; Manzocco, Lara; Nicoli, Maria Cristina; Hendrickx, Marc



Differences in the expression of the ASIP gene are involved in the recessive black coat colour pattern in sheep: evidence from the rare Xalda sheep breed  

Microsoft Academic Search

Summary Here we have tested the hypothesis of association between different levels of agouti signalling peptide (ASIP) mRNA and the recessive black coat colour in the rare Xalda breed of sheep. To deal with this task, we first tested the possible action of both the dominant black extension allele (ED) and a 5-bp deletion (X99692:c.100_104del; Adel) in the ovine ASIP

L. J. Royo; I. Álvarez; J. J. Arranz; I. Fernández; A. Rodríguez; L. Pérez-Pardal; F. Goyache



Quaternion Colour Texture  

Microsoft Academic Search

The quaternion representation of colour is shown to be effective in the context of colour texture region segmentation in digital colour images. The advantage of using quaternion arithmetic is that a colour can be represented and analyzed as a single entity. A basis for the colour textures occurring in a given image is derived via quaternion principal component analysis of

Lilong Shi; Brian Funt


How feather colour reflects its melanin content  

Microsoft Academic Search

Summary 1. Melanin coloration is the most common type of colour in animals. Many species use melanin-based black, brown, grey or earth-toned colours as intraspecific signals of quality. 2. Melanin comes in two main forms in vertebrates - eumelanin and phaeomelanin - and these are said to create different colours, with eumelanin giving a darker black, brown or grey appearance




Correlation between ethylene emission and skin colour changes during papaya (Carica papaya L.) fruit ripening  

NASA Astrophysics Data System (ADS)

The skin colour changes and ethylene emission rates were monitored during papaya (C. papaya L.) fruit ripening. Two groups of papaya (‘Formosa’ and ‘Solo’) were applied in this study. The total colour difference was used as measured parameter and the corresponding half time of its saturation was used as correlation parameter. A high correlation factor between the saturation half time and corresponding climacteric peak time was found. It was concluded that high ethylene emission rate in ‘Solo’ fruit promotes a quick change of the total colour difference.

da Silva, M. G.; Oliveira, J. G.; Vitoria, A. P.; Corrêa, S. F.; Pereira, M. G.; Campostrini, E.; Santos, E. O.; Cavalli, A.; Vargas, H.



Effect of different carotenoid-containing diets on the vitamin A levels and colour parameters in Iberian pigs' tissues: utility as biomarkers of traceability.  


Retinol and fat colour parameters in Iberian pigs fed on different carotenoid-containing diets were assessed. Thirty animals in two groups were considered: Iberian breed pigs fed on acorns and grass (Montanera) and on concentrate (Cebo). Carotenoids and retinoids were analysed in the diets and in plasma, liver and perirenal fat of the animals by HPLC and HPLC-MS. Retinol levels in plasma and fat were similar in Montanera and Cebo animals. The utility of retonids and colour parameters as traceability index was also explored. Retinoids in liver classified correctly 93% of the animals according to their diet L* and hab. CIELAB parameters of the perirenal fat discriminated correctly 78.6% of the animals according to their diet. L* values for the Montanera animals were significantly different (P<0.01) from those fed on concentrate. It can be claimed that the liver retinol profile and fat colour parameters can be useful for feeding traceability purposes in Iberian pigs breed in Montanera and Cebo. PMID:24967537

Alvarez, R; Vicario, I M; Meléndez-Martínez, A J; Alcalde, M J



Bumblebees (Bombus terrestris) and honeybees (Apis mellifera) prefer similar colours of higher spectral purity over trained colours.  


Differences in the concentration of pigments as well as their composition and spatial arrangement cause intraspecific variation in the spectral signature of flowers. Known colour preferences and requirements for flower-constant foraging bees predict different responses to colour variability. In experimental settings, we simulated small variations of unicoloured petals and variations in the spatial arrangement of colours within tricoloured petals using artificial flowers and studied their impact on the colour choices of bumblebees and honeybees. Workers were trained to artificial flowers of a given colour and then given the simultaneous choice between three test colours: either the training colour, one colour of lower and one of higher spectral purity, or the training colour, one colour of lower and one of higher dominant wavelength; in all cases the perceptual contrast between the training colour and the additional test colours was similarly small. Bees preferred artificial test flowers which resembled the training colour with the exception that they preferred test colours with higher spectral purity over trained colours. Testing the behaviour of bees at artificial flowers displaying a centripetal or centrifugal arrangement of three equally sized colours with small differences in spectral purity, bees did not prefer any type of artificial flowers, but preferentially choose the most spectrally pure area for the first antenna contact at both types of artificial flowers. Our results indicate that innate preferences for flower colours of high spectral purity in pollinators might exert selective pressure on the evolution of flower colours. PMID:23224278

Rohde, Katja; Papiorek, Sarah; Lunau, Klaus



Missense and nonsense mutations in melanocortin 1 receptor (MC1R) gene of different goat breeds: association with red and black coat colour phenotypes but with unexpected evidences  

PubMed Central

Background Agouti and Extension loci control the relative amount of eumelanin and pheomelanin production in melanocytes that, in turn, affects pigmentation of skin and hair. The Extension locus encodes the melanocortin 1 receptor (MC1R) whose permanent activation, caused by functional mutations, results in black coat colour, whereas other inactivating mutations cause red coat colour in different mammals. Results The whole coding region of the MC1R gene was sequenced in goats of six different breeds showing different coat colours (Girgentana, white cream with usually small red spots in the face; Maltese, white with black cheeks and ears; Derivata di Siria, solid red; Murciano-Granadina, solid black or solid brown; Camosciata delle Alpi, brown with black stripes; Saanen, white; F1 goats and the parental animals). Five single nucleotide polymorphisms (SNPs) were identified: one nonsense mutation (p.Q225X), three missense mutations (p.A81V, p.F250V, and p.C267W), and one silent mutation. The stop codon at position 225 should cause the production of a shorter MC1R protein whose functionality may be altered. These SNPs were investigated in a larger sample of animals belonging to the six breeds. The Girgentana breed was almost fixed for the p.225X allele. However, there was not complete association between the presence of red spots in the face and the presence of this allele in homozygous condition. The same allele was identified in the Derivata di Siria breed. However, its frequency was only 33%, despite the fact that these animals are completely red. The p.267W allele was present in all Murciano-Granadina black goats, whereas it was never identified in the brown ones. Moreover, the same substitution was present in almost all Maltese goats providing evidence of association between this mutation and black coat colour. Conclusion According to the results obtained in the investigated goat breeds, MC1R mutations may determine eumelanic and pheomelanic phenotypes. However, they are probably not the only factors. In particular, the surprising not complete association of the nonsense mutation (p.Q225X) with red coat colour raises a few hypotheses on the determination of pheomelanic phenotypes in goats that should be further investigated.



Colour Graphics for Hydrocode Simulations.  

National Technical Information Service (NTIS)

This report describes the production of colour graphical output for the two dimensional finite difference reactive hydrocodes currently used by Weapons Systems Division. The programs use the NCAR graphics package and show how the careful choice appropriat...

A. Doyle D. A. Jones G. Kemister



Total column density variations of ozone (O3) in presence of different types of clouds  

NASA Astrophysics Data System (ADS)

The zenith sky scattered light spectra were carried out using zenith sky UV-visible spectrometer in clear and cloudy sky conditions during May-November 2000 over the tropical station Pune (18°32'N, 73°51'E). These scattered spectra are obtained in the spectral range 462-498 nm between 75° and 92° solar zenith angles (SZAs). The slant column densities (SCDs) as well as total column densities (TCDs) of NO2, O3, H2O and O4 are derived with different SZAs in clear and cloudy sky conditions. The large enhancements and reductions in TCDs of the above gases are observed in thick cumulonimbus (Cb) clouds and thin high cirrus (Ci) clouds, respectively, compared to clear sky conditions. The enhancements in TCDs of O3 appear to be due to photon diffusion, multiple Mie-scattering and multiple reflections between layered clouds or isolated patches of optically thick clouds. The reductions in TCDs due to optically thin clouds are noticed during the above period. The variations in TCDs of O3 measured under cloudy sky are discussed with total cloud cover (octas) of different types of clouds such as low clouds ( C L ), medium clouds ( C M ) and high clouds ( C H ) during May-November 2000. The variations in TCDs of O3 measured in cloudy sky conditions are found to be well matched with cloud sensitive parameter colour index (CI) and found to be in good correlation. The TCDcloudy are derived using airmass factors (AMFs) computed without considering cloud cover and CI in radiative transfer (RT) model, whereas TCDmodel are derived using AMFs computed with considering cloud cover, cloud height and CI in RT model. The TCDmodel is the column density of illuminated cloudy effect. A good agreement is observed between TCDmodel, TCDDob and TCDGOME.

Meena, G. S.



Inheritance of seed colour in turnip rape ( Brassica campestris L.)  

Microsoft Academic Search

The inheritance of seed colour was investigated in the progenies of crosses between seven yellow seeded forms and a brown seeded one of turnip rape (Brassica campestris L.). Seed colour differences were found to be determined in each case by one or two genes with epistatic effect. Moreover, independent inheritance of hilum colour was observed. Seed colour was predominantly but

A. Schwetka



Differences in the expression of the ASIP gene are involved in the recessive black coat colour pattern in sheep: evidence from the rare Xalda sheep breed.  


Here we have tested the hypothesis of association between different levels of agouti signalling peptide (ASIP) mRNA and the recessive black coat colour in the rare Xalda breed of sheep. To deal with this task, we first tested the possible action of both the dominant black extension allele (E(D)) and a 5-bp deletion (X99692:c.100_104del; A(del)) in the ovine ASIP coding sequence on the black coat colour pattern in 188 Xalda individuals. The E(D) allele was not present in the sample and only 11 individuals were homozygous for the A(del)ASIP allele. All Xalda individuals carrying the A(del)/A(del) genotype were phenotypically black. However, most black-coated individuals (109 out of 120) were not homozygous for the 5-bp deletion, thus rejecting the A(del)/A(del) genotype as the sole cause of recessive black coat colour in sheep. Differences in expression of ASIP mRNA were assessed via RT-PCR in 14 black-coated and 10 white-coated Xalda individuals showing different ASIP genotypes (A(wt)/A(wt), A(wt)/A(del) and A(del)/A(del)). Levels of expression in black animals were significantly (P < 0.0001) lower than those assessed for white-coated individuals. However, the ASIP genotype did not influence the ASIP mRNA level of expression. The consistency of these findings with those recently reported in humans is discussed, and the need to isolate the promoter region of ovine ASIP to obtain further evidence for a role of ASIP in recessive black ovine pigmentation is pointed out. PMID:18384465

Royo, L J; Alvarez, I; Arranz, J J; Fernández, I; Rodríguez, A; Pérez-Pardal, L; Goyache, F



Colour Perception in ADHD  

ERIC Educational Resources Information Center

Attention-deficit/hyperactivity disorder (ADHD) is associated with unexplained impairments on speeded naming of coloured stimuli. These deficits may reflect hypofunctioning retinal dopaminergic mechanisms impairing particularly blue-yellow colour discrimination. Colour perception and rapid colour naming ability were investigated in 14 children…

Banaschewski, Tobias; Ruppert, Sinje; Tannock, Rosemary; Albrecht, Bjorn; Becker, Andreas; Uebel, Henrik; Sergeant, Joseph A.; Rothenberger, Aribert



Colour-space distortion in women who are heterozygous for colour deficiency.  


We examined colour perception among a group of women heterozygous for colour vision deficiency. Judgements of colour dissimilarity were collected by presenting colour stimuli in groups of three for odd-one-out decisions. The judgements were summarised as one consensus colour space for the heterozygotes and another for age-matched controls. Individual differences MDS was also applied, resulting in a single colour space which can be adjusted to fit each subject's responses individually by compressing it along its axes. Heterozygous women showed a trend towards colour-space compression in a red-green dimension, or reduced salience of that dimension compared to controls, though less extreme than found in overt colour deficiency. PMID:19167418

Bimler, David; Kirkland, John



Characterisation of betalain patterns of differently coloured inflorescences from Gomphrena globosa L. and Bougainvillea sp. by HPLC-DAD-ESI-MSn.  


In the present study, the betaxanthin (bx) and betacyanin patterns of differently coloured inflorescences from Gomphrena globosa L. and Bougainvillea sp. have been investigated in detail by applying reversed phase high-performance liquid chromatography-diode array detection (HPLC-DAD) coupled with positive ion electrospray mass spectrometry. Histidine-bx was found to be the predominant betaxanthin of Gomphrena globosa inflorescences. Furthermore, arginine-bx was detected as a novel betaxanthin, which to the best of our knowledge has not been reported as a pigment that occurs naturally so far. Dopa-bx was the major betaxanthin of Bougainvillea sp., although several minor betaxanthins were also present, including lysine-bx and putrescine-bx, novel betaxanthins hitherto not observed naturally. Remarkable differences in the betacyanin patterns between the purple, red and orange varieties were observed for both Gomphrena and Bougainvillea inflorescences. Hence, both the betacyanin profiles and the relative betaxanthin:betacyanin ratios determine the broad colour palette of Gomphrena petals and Bougainvillea bracts. PMID:17139486

Kugler, Florian; Stintzing, Florian C; Carle, Reinhold



Different Signatures of the Total Filling Factor 1 State  

NASA Astrophysics Data System (ADS)

Bringing two 2-dimensional electron systems in close proximity can yield a correlated state as the electrons will experience the presence of the neighboring system. At the individual filling factors of 1/2 this leads to a new double-layer ground state as positive and negative charges from opposite layers couple to excitons. Many remarkable properties were found such as vanishing Hall and longitudinal resistances in the counterflow configuration [1], a resonantly enhanced zero bias tunneling peak [2], and more recently, a critical DC tunneling current and vanishingly small interlayer resistances in DC measurements [3]. We will show how it is possible to combine the results of these three different measurements into a consistent picture. Under certain conditions it is possible to exceed the critical currents but still observe a minimum at total filling factor 1 in the counterflow configuration.[1] M. Kellogg et al. PRL 93, 036801 (2004); E. Tutuc et al. PRL 93, 036802 (2004)[2] I.B. Spielman et al., PRL 87, 036803 (2001)[3] L. Tiemann et al., New Journal of Physics 10, 045018 (2008)

Tiemann, Lars; Yoon, Youngsoo; Schmult, Stefan; Hauser, Maik; Dietsche, Werner; von Klitzing, Klaus



The Active Human Gut Microbiota Differs from the Total Microbiota  

PubMed Central

The human gut microbiota is considered one of the most fascinating reservoirs of microbial diversity hosting between 400 to 1000 bacterial species distributed among nine phyla with Firmicutes, Bacteroidetes and Actinobacteria representing around of the diversity. One of the most intriguing issues relates to understanding which microbial groups are active players in the maintenance of the microbiota homeostasis. Here, we describe the diversity of active microbial fractions compared with the whole community from raw human fecal samples. We studied four healthy volunteers by 16S rDNA gene pyrosequencing. The fractions were obtained by cell sorting based on bacterial RNA concentration. Bacterial families were observed to appear or disappear on applying a cell sorting method in which flow cytometry was used to evaluate the active cells by pyronin-Y staining of RNA. This method was able to detect active bacteria, indicating that the active players differed from that observed in raw fecal material. Generally, observations showed that in the active fractions, the number of reads related to Bacteroidetes decreased whereas several families from Clostridiales (Firmicutes) were more highly represented. Moreover, a huge number of families appeared as part of the active fraction when cell sorting was applied, indicating reads that are simply statistically hidden by the total reads.

Peris-Bondia, Francesc; Latorre, Amparo; Artacho, Alejandro; Moya, Andres; D'Auria, Giuseppe



Subtle design changes control the difference in colour reflection from the dorsal and ventral wing-membrane surfaces of the damselfly Matronoides cyaneipennis.  


The hind wings of males of the damselfly Matronoides cyaneipennis exhibit iridescence that is blue dorsally and green ventrally. These structures are used semiotically in agonistic and courtship display. Transmission electron microscopy reveals these colours are due to two near-identical 5-layer distributed Bragg reflectors, one placed either side of the wing membrane. Interestingly the thicknesses of corresponding layers in each distributed Bragg reflector are very similar for all but the second layer from each outer surface. This one key difference creates the significant disparity between the reflected spectra from the distributed Bragg reflectors and the observed colours of either side of the wing. Modelling indicates that modifications to the thickness of this layer alone create a greater change in the peak reflected wavelength than is observed for similar modifications to the thickness of any other layer. This results in an optimised and highly effective pair of semiotic reflector systems, based on extremely comparable design parameters, with relatively low material and biomechanical costs. PMID:23389130

Nixon, M R; Orr, A G; Vukusic, P



Colour Vision and Colour Vision Theories  

Microsoft Academic Search

IN a recent letter to NATURE (September 29, p. 473) Dr. Edridge-Green has condemned the colour theory of Young and Helmholtz by the sweeping statement: ``There is no fact that directly supports the trichromatic theory.'' It is scarcely credible that such men of science as Young, Helmholtz, Maxwell, and Abney could have deliberately adopted a theory of colour vision with

Frank Allen



Advanced colour matching theory  

Microsoft Academic Search

Traditionally, computer colour matching systems have employed the Kubelka-Munk algorithms. This approach makes many assumptions which do not hold true when colour matching in non-hiding applications such as printing inks, plastics and woodstains. A many flux mathematical model has been proven to give accurate colour matches across all regions of optical density. The GretagMacbeth ProPalette™ colour matching software employs this

Colin Wakeford



Colour, Theories of  

Microsoft Academic Search

The world as perceived by human beings is full of colour. The world as described by physical scientists is composed of colourless particles and fields. Philosophical theories of colour since the scientific revolution have been primarily driven by a desire to harmonize these two apparently conflicting pictures of the world. Any adequate theory of colour has to be consistent with

David R. Hilbert


Representing object colour in language comprehension.  


Embodied theories of cognition hold that mentally representing something red engages the neural subsystems that respond to environmental perception of that colour. This paper examines whether implicit perceptual information on object colour is represented during sentence comprehension even though doing so does not necessarily facilitate task performance. After reading a sentence that implied a particular colour for a given object, participants were presented with a picture of the object that either matched or mismatched the implied colour. When asked if the pictured object was mentioned in the preceding sentence, people's responses were faster when the colours mismatched than when they matched, suggesting that object colour is represented differently to other object properties such as shape and orientation. A distinction between stable and unstable embodied representations is proposed to allow embodied theories to account for these findings. PMID:16616075

Connell, Louise



The quality of protein of coloured fleshed potatoes.  


Potatoes of purple varieties and red flesh colour were estimated as the important food product containing valuable protein. Amino acids concentration and protein nutritive value of coloured potatoes were analysed and compared with traditional yellow-fleshed varieties. Studies comprised potatoes of 13 varieties: 7 of purple-fleshed, four of red-fleshed and two of yellow-fleshed. There were observed differences between studied potatoes with respect to dry matter, starch and protein content as well as to amino acids concentration and protein quality independently on flesh colour. Potatoes of low as well of high content of total protein, independently on flesh colour, characterised similar protein quality, like for example varieties of Blaue Anneliese and Highland B. Red or Blue Congo and Salad Blue. Leucine limited the quality of majority of coloured fleshed potato varieties used for the experiment. The best amino acid profiles and protein quality confirmed by chemical scores and EAA index values characterised purple fleshed Vitelotte and Blaue Anneliese, yellow fleshed Verdi as well as red fleshed Herbie 26, Highland B. Red and Rosemarie. PMID:23871046

P?ksa, A; Kita, A; Ku?akowska, K; Anio?owska, M; Hamouz, K; Nem?, A



Molecular variation in pigmentation genes contributing to coat colour in native Korean Hanwoo cattle.  


Pigmentation genes such as TYR (tyrosinase), TYRP1 (tyrosinase-related protein 1), DCT (previously TYRP2, or tyrosinase-related protein 2), ASIP (agouti) and MC1R (melanocortin receptor 1) play a major role in cattle coat colour. To understand the genotypic profile underlying coat colour in native Korean Hanwoo cattle and Angus black cattle, portions of the above-mentioned genes were amplified. Sequence analysis revealed variation in the TYRP1 (exon 5) and MC1R genes. Restriction enzyme analysis of these two genes could distinguish between different colours of Hanwoo cattle. Quantitative estimates of melanin and eumelanin in hair from three different-coloured Hanwoo phenotypes and Angus black showed significant differences at the breed and phenotypic levels. Finally, sequence variants in MC1R were associated with total melanin and eumelanin in breeds as well as in Hanwoo phenotypes. PMID:18557975

Mohanty, T R; Seo, K S; Park, K M; Choi, T J; Choe, H S; Baik, D H; Hwang, I H



Prevalence of colour blindness in young Jordanians.  


Colour blindness is one of the common genetic disorders observed in all human populations. It is a sex-linked recessive trait. The genes are located on the X chromosome within the Xq28 band. 1,418 university students (1,200 female and 218 male) from Zarka Private University and the Hashemite University were randomly selected and tested for congenital red/green colour blindness, by using Ishihara pseudo-isochromatic colour plates. A total of 23 individuals were found to be colour blind. In females, 4 students (0.33%) were colour blind: 1 of them showed protanomalia, 1 protanopia and 2 deuteranomalia. In males, 19 students (8.72%) were colour blind: 4 showed protanomalia, 3 protanopia, 8 deuteranomalia and 4 deuteranopia. The allelic frequencies of the colour vision gene were found to be 0.087 in males, 0.003 in females and 0.016 in the total population. Studies on colour blindness in Jordan are very few; this population-based investigation is meant to fill a gap in this field. PMID:11125268

Al-Aqtum, M T; Al-Qawasmeh, M H



Responsiveness and minimal important differences after revision total hip arthroplasty  

Microsoft Academic Search

BACKGROUND: The health-related quality of life (HRQoL) is currently weighted more heavily when evaluating health status, particularly regarding medical treatments and interventions. However, it is rarely used by physicians to compare responsiveness. Additionally, responsiveness estimates derived by the Harris Hip Score (HHS) and the Short Form 36 (SF-36) before and after revision total hip arthroplasty (THA) have not been clinically

Hon-Yi Shi; Je-Ken Chang; Chi-Yin Wong; Jun-Wen Wang; Yuan-Kun Tu; Herng-Chia Chiu; King-Teh Lee



Effects of soaking, boiling and autoclaving on the phenolic contents and antioxidant activities of faba beans (Vicia faba L.) differing in seed coat colours.  


The Australian grown faba beans of different seed coat colours were either soaked, boiled or autoclaved, and analysed for phenolic contents and antioxidant activity using an array of reagent-based assays. Soaking, boiling and autoclaving were shown to lower the level of active compounds in faba beans. A significant amount of active compounds was leached to the soaking and cooking medium. Boiling was a better method in retaining active compounds in beans than autoclaving. The boiled beans had more active compounds than those of resulting cooking broths, which was the opposite observation when autoclaving. The buff-genotypes had a similar level of active compounds to red- and green-genotypes. The high performance liquid chromatography-post column derivatisation (HPLC-PCD) system detected a dense collection of high antioxidant HPLC peaks ('humps') in extracts of raw, soaked and boiled beans. The present findings encouraged consumption of faba beans together with cooking broth for the maximum potential health benefits. PMID:24001866

Siah, Siem; Wood, Jennifer A; Agboola, Samson; Konczak, Izabela; Blanchard, Christopher L



Differences in Colour Gamut Obtained with Three Synthetic Red Food Colorants Compared with Three Natural Ones. pH and Heat Stability  

Microsoft Academic Search

The current trend in European markets towards natural ingredients has stimulated the interest in natural colorants. When it is decided to replace a colorant, normally a synthetic colorant with a natural one, it is interesting to know how the colour would be perceived, by locating their coordinates in the a*b*-diagram. The colours of three red natural colorants and three red

A. Arocas; P. Varela; A. Salvador; F. J. Heredia; S. M. Fiszman



"Close" Encounters...of a Totally Different Kind.  

ERIC Educational Resources Information Center

Presents a project used in an advanced art class in which students focus on the work of Chuck Close by creating large self-portraits in the manner of Close. Describes the work of different students, such as how one student made a portrait using different colors of Skittles candy. (CMK)

Greenman, Geri



Artist's colour rendering of HDR scenes in 3D Mondrian colour-constancy experiments  

Microsoft Academic Search

The presentation provides an update on ongoing research using three-dimensional Colour Mondrians. Two still life arrangements comprising hand-painted coloured blocks of 11 different colours were subjected to two different lighting conditions of a nearly uniform light and directed spotlights. The three-dimensional nature of these test targets adds shadows and multiple reflections, not found in flat Mondrian targets. Working from exactly

Carinna E. Parraman; John J. McCann; Alessandro Rizzi



Colour mathematics: with graphs and numbers  

NASA Astrophysics Data System (ADS)

The different combinations involved in additive and subtractive colour mixing can often be difficult for students to remember. Using transmission graphs for filters of the primary colours and a numerical scheme to write out the relationships are good exercises in analytical thinking that can help students recall the combinations rather than just attempting to memorize them.

Lo Presto, Michael C.



Colour Mathematics: With Graphs and Numbers  

ERIC Educational Resources Information Center

The different combinations involved in additive and subtractive colour mixing can often be difficult for students to remember. Using transmission graphs for filters of the primary colours and a numerical scheme to write out the relationships are good exercises in analytical thinking that can help students recall the combinations rather than just…

LoPresto, Michael C.



Visual effects of wall colours in living rooms  

Microsoft Academic Search

The visual effects of wall colours were quantified as the purpose of basic research to create a comfortable atmosphere by applying the visual effects of colours to interior colour design. The experiment was conducted at three different temperatures of 10, 25 and 40°C, and at a constant relative humidity of 60%. Slides of 1\\/10-scale living room models of different wall




Colour constancy in insects.  


Colour constancy is the perceptual phenomenon that the colour of an object appears largely unchanged, even if the spectral composition of the illuminating light changes. Colour constancy has been found in all insect species so far tested. Especially the pollinating insects offer a remarkable opportunity to study the ecological significance of colour constancy since they spend much of their adult lives identifying and choosing between colour targets (flowers) under continuously changing ambient lighting conditions. In bees, whose colour vision is best studied among the insects, the compensation provided by colour constancy is only partial and its efficiency depends on the area of colour space. There is no evidence for complete 'discounting' of the illuminant in bees, and the spectral composition of the light can itself be used as adaptive information. In patchy illumination, bees adjust their spatial foraging to minimise transitions between variously illuminated zones. Modelling allows the quantification of the adaptive benefits of various colour constancy mechanisms in the economy of nature. We also discuss the neural mechanisms and cognitive operations that might underpin colour constancy in insects. PMID:24647930

Chittka, Lars; Faruq, Samia; Skorupski, Peter; Werner, Annette



Across light: through colour  

NASA Astrophysics Data System (ADS)

The speed at which our world is changing is reflected in the shifting way artistic images are created and produced. Holography can be used as a medium to express the perception of space with light and colour and to make the material and the immaterial experiments with optical and digital holography. This paper intends to be a reflection on the final product of that process surrounding a debate of ideas for new experimental methodologies applied to holographic images. Holography is a time-based medium and the irretrievable linear flow of time is responsible for a drama, unique to traditional cinematography. If the viewers move to left or right, they see glimpses of the next scene or the previous one perceived a second ago. This interaction of synthetic space arises questions such as: can we see, in "reality", two forms in the same space? Trying to answer this question, a series of works has been created. These concepts are embryonic to a series of digital art holograms and lenticulars technique's titled "Across Light: Through Colour". They required some technical research and comparison between effects from different camera types, using Canon IS3 and Sony HDR CX105.

Azevedo, Isabel; Richardson, Martin; Bernardo, Luis Miguel



The colours of cloaks  

NASA Astrophysics Data System (ADS)

We present a survey of results from various research groups under the unifying viewpoint of transformational physics, which has been recently introduced for the design of metamaterials in optics and acoustics. We illustrate the versatility of underlying geometric transforms in order to bridge wave phenomena (the different 'colours' of waves) ranging from transverse electric waves, to linear surface water waves at an air-fluid interface, to pressure waves in fluids and out-of-plane shear waves in elastic media: these waves are all governed by a second order scalar partial differential equation (PDE) invariant under geometric transform. Moreover, flexural waves propagating in thin plates represent a very peculiar situation whereby the displacement field satisfies a fourth order scalar PDE which also retains its form under geometric transform (unlike for the Navier equation in elastodynamics). Control of flexural wave trajectories is illustrated with a multilayered cloak and a carpet. Interestingly, the colours of waves can be revealed through an analysis of the band spectra of invisibility cloaks. In the context of acoustics, this suggests one can hear the shape of a drum. Alternative avenues towards cloaking based upon anomalous resonances of a negatively refracting coating (which can be seen as the result of folding the space back onto itself), and even plasmonic shells reducing the scattering cross-section of nano-objects are also addressed.

Guenneau, Sébastien; McPhedran, Ross C.; Enoch, Stefan; Movchan, Alexander B.; Farhat, Mohamed; Nicorovici, Nicolae-Alexandru P.



Colour constancy as counterfactual  

Microsoft Academic Search

There is nothing in this World constant but Inconstancy.[Swift 1711: 258]In this paper I argue that two standard characterizations of colour constancy are inadequate to the phenomenon. This inadequacy matters, since, I contend, philosophical appeals to colour constancy as a way of motivating illumination-independent conceptions of colour turn crucially on the shortcomings of these characterizations. After critically reviewing the standard

Jonathan Cohen



Colour displays for categorical images  

Microsoft Academic Search

We propose a method for identifying a set of colours for displaying 2D and 3D categorical images when the categories are unordered labels. The principle is to find maximally distinct sets of colours. We either generate colours sequentially, to maximize the dissimilarity or distance between a new colour and the set of colours already chosen, or use a simulated annealing

Chris Glasbey; Heijden van der G. W. A. M; V. F. K. Toh; Alision Gray



A Study of the Different Uses of Colour Channels for Traffic Sign Recognition on Hierarchical Temporal Memory  

Microsoft Academic Search

When designing intelligence for a car many different tasks can be performed. Some of these tasks cannot easily be performed by conventional algorithms in comparison with the human brain. Recently, such intelligence has often been reached by using probability based systems. In this paper, Hierarchical Temporal Memory (HTM) is used to implement one of these tasks, namely traffic sign recognition.

W. J. C. Melis; M. Kameyama



Colour based human motion tracking for home-based rehabilitation  

Microsoft Academic Search

Abstract - In this paper, we propose a colour based trackingal gorithm for capturing the motionof hu man body parts for home-based rehabilitation. Different colour belts are attached to the bodyjo ints ofin terest andtra cked in the video sequence. The performance of the colour-based tracking algorithm is ,analysed by comparing the tracking results with the results from a commercial

Yaqin Tao; Huosheng Hu



Colour Vision in Migraine: Selective Deficits for SCone Discriminations  

Microsoft Academic Search

Three studies are reported that explore colour perception in migraine. In each, sensitivity for colours detected selectively by the S-cones and the L- and M-cones was assessed separately. The first study assessed the discrimination of small colour differences using the Farnsworth-Munsell 100-hue test. The second assessed threshold detection for purple, yellow, red and green targets on five equiluminant background colours.

AJ Shepherd



Skin colour and bilirubin in neonates.  

PubMed Central

The correlation between the yellow colour of the skin and serum bilirubin concentration, reserve albumin concentration, and pH was investigated in 76 icteric neonates. Significant linear correlation existed between yellow colour of the skin and serum bilirubin concentration, reciprocal of the reserve albumin concentration, and the squared hydrogen ion concentration. Furthermore, the basic yellowness of the skin at birth correlated linearily with the yellow colour of the skin measured when the child became jaundiced. The results support the proposed hypothesis that bilirubin is transferred from plasma to skin through two different mechanisms: (a) leakage of bilirubin-albumin complexes into extravascular spaces and (b) precipitation of bilirubin acid in phospholipid membranes. The latter mechanism suggests that measurement of the yellow colour of the skin may be a better predictor of brain damage than the serum bilirubin concentration and thus be of clinical utility. Measurement of the yellow colour of the skin as a method of obtaining serum bilirubin concentration is unreliable.

Knudsen, A; Brodersen, R



Shelflife and colour change kinetics of Aloe vera gel powder under accelerated storage in three different packaging materials  

Microsoft Academic Search

Aloe vera gel powder was produced through dehumidified air drying of Aloe vere gel at optimized conditions of temperature,\\u000a relative humidity and air velocity of 64 °C, 18% and 0.8 m.s?1, respectively. The powder was packed in three different packaging materials viz., laminated aluminum foil (AF), biaxially oriented polypropylene (BOPP) and polypropylene (PP). The shelf-life of the powder\\u000a was predicted on the

C. T. Ramachandra; P. Srinivasa Rao


Colour knowledge: the role of the right hemisphere in colour processing and object colour knowledge.  


The lateralisation of colour processing is not well understood, although there is a reasonable amount of evidence indicating a right hemisphere bias for colour processing. Tasks that require colour naming are associated with a left hemisphere bias and it is likely that asymmetry of colour processing is influenced by task demands. It is not known whether object colour knowledge is lateralised. In the current study colour and achromatic Mondrian-like objects were presented to either the left or right hemisphere to assess the lateralisation of colour processing. Participants were required to judge whether the objects were colour or achromatic. To assess colour knowledge, congruently and incongruently coloured familiar objects were presented to either the left or right hemisphere and participants were required to judge whether the objects were correctly or incorrectly coloured. The data show that both colour processing and colour knowledge are associated with a right hemisphere bias. PMID:18608853

Barnett, Kylie J



Colour, myoglobin denaturation and storage stability of raw and cooked mutton chops at different end point cooking temperature.  


In our study effect of different end point temperature (51 °C, 65 °C, 71 °C and 79 °C) on physicochemical and storage stability of mutton chops were evaluated. The L* (lightness) value and b* (yellowness) increased (P?

Sen, A R; Naveena, B M; Muthukumar, M; Vaithiyanathan, S



Colour Vision and Colour Vision Theories  

Microsoft Academic Search

IN the first of my two recent letters on this subject I selected five of the cases in which Dr. Edridge-Green asserts that the trichromatic theory cannot explain certain phenomena of colour vision; and I indicated, in each case, the source of his error. In more than one case I gave the full proof. In his reply he took no

W. Peddie



Colour Vision and Colour Vision Theories  

Microsoft Academic Search

PROF. PEDDIE, in NATURE of August 4, p. 163, has dealt with some of my strictures of the trichromatic theory. Whilst nothing can be said against his mathematical presentation of the theory, it can easily be shown that, when a case of colour blindness is fully and carefully examined, the mathematical presentation will not account for the facts. All the

F. W. Edridge-Green



Quantification of Japanese quail eggshell colour by image analysis.  


The Japanese quail lays eggs with colourful and patterned shells which make the eggshell colour difficult to classify. In this study, the method of measuring colour of patchy eggs using image analyses and its power to discriminate among individual variation were established. Estimated repeatability for egg colour and proportion of patterned areas was high (>0.58), suggesting intermedíate or high heritability of eggshell colour characteristics. Three components have been identified as significant in discriminant function analysis. These three components explained 91.4% of the total variance in egg colour characteristics. In cluster analysis, 78.3% of the eggs that were collected from 15 females were correctly classified. This study indicates that eggshell colour characteristics can be reliably studied by image analyses and that this method can provide a unified character list for future examinations and interpretations of quail egg characteristics. PMID:19621137

Sezer, Metin; Tekelioglu, Oguz



Colour constancy in the swallowtail butterfly Papilio xuthus.  


We have recently shown that the Japanese yellow swallowtail butterfly Papilio xuthus uses colour vision when searching for food. In the field, these butterflies feed on nectar provided by flowers of various colours not only in direct sunlight but also in shaded places and on cloudy days, suggesting that they have colour constancy. Here, we tested this hypothesis. We trained newly emerged Papilio xuthus to feed on sucrose solution on a paper patch of a certain colour under white illumination. The butterflies were then tested under both white and coloured illumination. Under white illumination, yellow- and red-trained butterflies selected the correctly coloured patch from a four-colour pattern and from a colour Mondrian collage. Under four different colours of illumination, we obtained results that were fundamentally similar to those under white illumination. Moreover, we performed critical tests using sets of two similar colours, which were also correctly discriminated by trained butterflies under coloured illumination. Taken together, we conclude that the butterfly Papilio xuthus exhibits some degree of colour constancy when searching for food. PMID:11060214

Kinoshita, M; Arikawa, K



Object knowledge modulates colour appearance  

PubMed Central

We investigated the memory colour effect for colour diagnostic artificial objects. Since knowledge about these objects and their colours has been learned in everyday life, these stimuli allow the investigation of the influence of acquired object knowledge on colour appearance. These investigations are relevant for questions about how object and colour information in high-level vision interact as well as for research about the influence of learning and experience on perception in general. In order to identify suitable artificial objects, we developed a reaction time paradigm that measures (subjective) colour diagnosticity. In the main experiment, participants adjusted sixteen such objects to their typical colour as well as to grey. If the achromatic object appears in its typical colour, then participants should adjust it to the opponent colour in order to subjectively perceive it as grey. We found that knowledge about the typical colour influences the colour appearance of artificial objects. This effect was particularly strong along the daylight axis.

Witzel, Christoph; Valkova, Hanna; Hansen, Thorsten; Gegenfurtner, Karl R



The connotations of colour terms: colour based X-phemisms  

Microsoft Academic Search

This paper investigates the connotations of colour terms with particular attention to figurative uses of black, white, grey, brown, yellow, red, green, blue and a few miscellaneous colours. The connotations are judged on the basis of whether the phrases in which the colour terms occur are typically orthophemistic, euphemistic, or dysphemistic. All the colours surveyed have some, often many, orthophemistic

Keith Allan


The Brightness of Colour  

Microsoft Academic Search

BackgroundThe perception of brightness depends on spatial context: the same stimulus can appear light or dark depending on what surrounds it. A less well-known but equally important contextual phenomenon is that the colour of a stimulus can also alter its brightness. Specifically, stimuli that are more saturated (i.e. purer in colour) appear brighter than stimuli that are less saturated at

David Corney; John-Dylan Haynes; Geraint Rees; R. Beau Lotto; Olaf Sporns



Stability of memory for colour in context.  


Memory for colours presented in isolation was compared with that for colours presented as part of a clip-art image or as part of a non-meaningful, Mondrian-like image. The area under the Receiver Operating Characteristic for deciding that two colours, presented at different delay intervals, were the same or different provided an index of memory for colour. The provision of a context reduced the decay of memory, regardless of whether the context was meaningful (clip-art images) or non-meaningful (Mondrian-like images). The result was seen as a generalisation of the auditory phenomenon of profile analysis, in which memory for the amplitude of a single component of a complex sound is more stable than that for the component in isolation. PMID:10320866

Francis, M A; Irwin, R J



The colour of the human skull.  


The colour of the human skull was determined from 124 fresh skull samples using the tristimulus colour measurement system "Micro Color" and listed as The Commission Internationale de l'Eclairage (CIE) L*a*b*-values. The skulls were found to be relatively light (L*=72.5), nearly colourless on the a*-axis (a*=-7.4), and slightly yellow (b*=16.4). No difference was found between the colours of the outer and the inner surfaces of the skulls. Including a small number (n=8) of skulls from diabetic patients in the study, we detected no colour difference between the samples from diabetics and non-diabetics. However, a hitherto unknown correlation between the subjects' age and the yellowness (b*-value) of the skull could be demonstrated. PMID:11230946

Schafer, A T



Colour Mixing Based on Daylight  

ERIC Educational Resources Information Center

Colour science is based on the sensation of monochromatic light. In contrast to that, surface colours are caused by reflection of wide sections of the daylight spectrum. Non-spectral colours like magenta and purple appear homologous to colours with spectral hue, if the approach of mixing monochromatic light is abandoned. It is shown that a large…

Meyn, Jan-Peter



Tetrachromatic colour space  

NASA Astrophysics Data System (ADS)

We derive colour spaces of the hue-colourfulness-luminance type, on the basis of a four-dimensional hypercube I4 (I = [0, 1]). The hypercube corresponds to a tetrachromatic colour system, analogous to the three-dimensional RGB cube. In the first derived space the colourfulness is chromatic saturation while in the second one, colourfulness refers to the vividness of the colour, even if it is achromatic. The hue is defined on the basis of an icositetrahedron of 24 triangles that is embedded in the boundary of the hypercube. The boundary of the hypercube is the polytope {4 3 3} (in Sclafli notation) that is a topological 3-sphere. Out of the 24 square faces in the boundary of the hypercube, 6 meet the black vertex and 6 meet the white vertex; the remaining 12 faces form a dodecahedron which is a topological 2-sphere. This equatorial or chromatic dodecahedron is used to define a hue for each point in the hypercube that is not on the achromatic segment; the icositetrahedron results from a division of each of the square faces of the dodecahedron into two triangles. In addition, a hexdecahedron of 16 square faces with the topology of a torus that is also embedded in the boundary of the hypercube, is used to define an alternate two-dimensional hue space.

Restrepo, Alfredo



Total Phenolic Content and Antimicrobial Activity of Different Lithuanian Propolis Solutions  

PubMed Central

The manufacture of ethanol-free propolis solutions offers a broader application. A few trials with Lithuanian propolis have been conducted. The aims of the study are to manufacture propolis water and water-free solutions and evaluate the quality and antimicrobial activity of these solutions. The studied solutions containing 2.5%, 5%, and 10% propolis are prepared. As solvents, purified water, 70%?v/v ethanol, 96.3%?v/v ethanol, propylene glycol, and their systems were used. Determination of total levels of phenolic compounds (FAE?mg/g) is based on colour oxidation-reduction reaction using Folin-Ciocalteu reagent under alkaline conditions and performed at 765?nm wavelength using UV spectrophotometer. The highest content of phenolic compounds was determined in solutions containing 10% propolis extracts, and the lowest amounts in 2.5% propolis extracts. The water extracted the lowest amount of phenolic compounds from crude propolis, ethanol extracted the highest amount, and propylene glycol ranked the middle position. It is determined that technological parameters (stirring, temperature) contribute to content of phenolic compounds. During microbiological study, MICs were determined. The studies showed that water extracted propolis solutions and solvents mixture did not inhibit the growth of the studied microorganisms, and propolis solutions in propylene glycol were found to have antimicrobial activity.

Ramanauskiene, Kristina; Inkeniene, Asta Marija; Petrikaite, Vilma; Briedis, Vitalis



The functional anatomy of imagining and perceiving colour.  


We report two functional magnetic resonance imaging experiments which reveal similarities and differences between perceptual and imaginal networks within the single visual submodality of colour. The first experiment contrasted viewing of a coloured and grey-scale Mondrian display, while the second contrasted a relative colour judgement with a spatial task and required the generation of mental images. Our results show that colour perception activates the posterior fusiform gyrus bilaterally (area V4), plus right-sided anterior fusiform and lingual gyri, striate cortex (area V1), and the left and right insula. Colour imagery activated right anterior fusiform gyrus, left insula, right hippocampus and parahippocampal gyrus, but not V4 or V1. The findings reconcile neurological case studies suggesting a double dissociation between deficits in colour imagery and perception and point to anterior fusiform, parahippocampal gyri and hippocampus as the location for stored representations of coloured objects. PMID:9601660

Howard, R J; ffytche, D H; Barnes, J; McKeefry, D; Ha, Y; Woodruff, P W; Bullmore, E T; Simmons, A; Williams, S C; David, A S; Brammer, M



Visual ecology of flies with particular reference to colour vision and colour preferences.  


The visual ecology of flies is outstanding among insects due to a combination of specific attributes. Flies' compound eyes possess an open rhabdom and thus separate rhabdomeres in each ommatidium assigned to two visual pathways. The highly sensitive, monovariant neural superposition system is based on the excitation of the peripheral rhabdomeres of the retinula cells R1-6 and controls optomotor reactions. The two forms of central rhabdomeres of R7/8 retinula cells in each ommatidium build up a system with four photoreceptors sensitive in different wavelength ranges and thought to account for colour vision. Evidence from wavelength discrimination tests suggests that all colour stimuli are assigned to one of just four colour categories, but cooperation of the two pathways is also evident. Flies use colour cues for various behavioural reactions such as flower visitation, proboscis extension, host finding, and egg deposition. Direct evidence for colour vision, the ability to discriminate colours according to spectral shape but independent of intensity, has been demonstrated for few fly species only. Indirect evidence for colour vision provided from electrophysiological recordings of the spectral sensitivity of photoreceptors and opsin genes indicates similar requisites in various flies; the flies' responses to coloured targets, however, are much more diverse. PMID:24664124

Lunau, Klaus



Diagnosing synaesthesia with online colour pickers: maximising sensitivity and specificity.  


The most commonly used method for formally assessing grapheme-colour synaesthesia (i.e., experiencing colours in response to letter and/or number stimuli) involves selecting colours from a large colour palette on several occasions and measuring consistency of the colours selected. However, the ability to diagnose synaesthesia using this method depends on several factors that have not been directly contrasted. These include the type of colour space used (e.g., RGB, HSV, CIELUV, CIELAB) and different measures of consistency (e.g., city block and Euclidean distance in colour space). This study aims to find the most reliable way of diagnosing grapheme-colour synaesthesia based on maximising sensitivity (i.e., ability of a test to identify true synaesthetes) and specificity (i.e., ability of a test to identify true non-synaesthetes). We show, applying ROC (receiver operating characteristics) to binary classification of a large sample of self-declared synaesthetes and non-synaesthetes, that the consistency criterion (i.e., cut-off value) for diagnosing synaesthesia is considerably higher than the current standard in the field. We also show that methods based on perceptual CIELUV and CIELAB colour models (rather than RGB and HSV colour representations) and Euclidean distances offer an even greater sensitivity and specificity than most currently used measures. Together, these findings offer improved heuristics for the behavioural assessment of grapheme-colour synaesthesia. PMID:23458658

Rothen, Nicolas; Seth, Anil K; Witzel, Christoph; Ward, Jamie



Colourful parrot feathers resist bacterial degradation  

PubMed Central

The brilliant red, orange and yellow colours of parrot feathers are the product of psittacofulvins, which are synthetic pigments known only from parrots. Recent evidence suggests that some pigments in bird feathers function not just as colour generators, but also preserve plumage integrity by increasing the resistance of feather keratin to bacterial degradation. We exposed a variety of colourful parrot feathers to feather-degrading Bacillus licheniformis and found that feathers with red psittacofulvins degraded at about the same rate as those with melanin and more slowly than white feathers, which lack pigments. Blue feathers, in which colour is based on the microstructural arrangement of keratin, air and melanin granules, and green feathers, which combine structural blue with yellow psittacofulvins, degraded at a rate similar to that of red and black feathers. These differences in resistance to bacterial degradation of differently coloured feathers suggest that colour patterns within the Psittaciformes may have evolved to resist bacterial degradation, in addition to their role in communication and camouflage.

Burtt, Edward H.; Schroeder, Max R.; Smith, Lauren A.; Sroka, Jenna E.; McGraw, Kevin J.



Efficient colour splitters for high-pixel-density image sensors  

NASA Astrophysics Data System (ADS)

When the pixel size of image sensors shrinks to the wavelength of light, this results in low signal levels for a given photon flux per pixel as a result of scaling laws. Because many image sensors require colour filters, it becomes crucial for small-pixel sensors to have an efficient filtering method that can capture all incident photons without absorbing them. Here, we propose a new method to split colours by using a microscale plate-like structure with a transparent medium that has a higher refractive index than the surrounding material. We experimentally demonstrate that this principle of colour splitting based on near-field deflection can generate colour images with minimal signal loss. From comparisons of the sum of the total integrated values for the colour channels, we confirm the amount of light received is 1.85 times that of the conventional colour filter method of the Bayer array, while maintaining the same level of resolution.

Nishiwaki, Seiji; Nakamura, Tatsuya; Hiramoto, Masao; Fujii, Toshiya; Suzuki, Masa-Aki



Colour Stability of Veneering Composites after Accelerated Aging  

PubMed Central

Objectives: To investigate the colour stability of four indirect composite restorative materials after accelerated aging. Methods: Four indirect composites (Gradia, Signum+, HFO and Adoro) were used. For each material, six specimens were prepared and subjected to accelerated aging (Suntest CPS+, Atlas, Chicago, IL, USA) according to ISO 7491. A Dr. Lange Microcolor Data Station colorimeter (Braive Instruments, Liege, Belgium) was used to measure specimen colour before and after aging. Measurements were performed according to the CIE L*a*b* system, and the mean L*, a* and b* values for each material were calculated. The equation ?E = [(?L*)2 + (?a*)2 + (?b*)2]1/2 was used to measure the total colour change (?E), where ?L*, ?a* and ?b* are the differences in the respective values before and after aging. One-way ANOVA were used to determine statistically significant differences in ?L*, ?a*, ?b* and ?E. Results: No statistically significant differences were found in ?L*, ?a*, ?b* and ?E among the materials tested (P?L*=.063; P?a*=.521; P?b*=.984 and P?E=.408). After aging, Gradia specimens showed an increase in lightness (?L*=0.36) and a green-yellow shift (?a*=?1.18, ?b*=0.6), while Signum+ specimens exhibited an increase in lightness (?L*=0.5) and a green-blue shift (?a*=?0.9, ?b*=?0.45). HFO specimens exhibited an increase in lightness (?L*=0.75) and a green-yellow shift (?a*=?1.3, ?b*=0.06), and Adoro specimens exhibited an increase in lightness (?L*=2.07) and a green-yellow shift (?a*=?1.3, ?b*=0.68). Conclusions: Colour changes were found to be within accepted values of perceptibility and clinical acceptance after accelerated aging, and no statistically significant differences were found in ?L*, ?a*, ?b* and ?E among the materials tested.

Papadopoulos, Triantafillos; Sarafianou, Aspasia; Hatzikyriakos, Andreas



2-Colour photolithography.  


Photolithography is a crucial technology for both research and industry. The desire to be able to create ever finer features has fuelled a push towards lithographic methods that use electromagnetic radiation or charged particles with the shortest possible wavelength. At the same time, the physics and chemistry involved in employing light or particles with short wavelengths present great challenges. A new class of approaches to photolithography on the nanoscale involves the use of photoresists that can be activated with one colour of visible or near-ultraviolet light and deactivated with a second colour. Such methods hold the promise of attaining lithographic resolution that rivals or even exceeds that currently sought by industry, while at the same time using wavelengths of light that are inexpensive to produce and can be manipulated readily. The physical chemistry of 2-colour photolithography is a rich area of science that is only now beginning to be explored. PMID:24705478

Fourkas, John T; Petersen, John S



Plumage colour mutations and melanins in the feathers of the Japanese quail: a first comparison.  


The absorbance of melanin content from dorsal feathers was compared between wild-type Japanese quail and nine other quail plumage colours determined by single mutations in one of seven genes: extended brown (MC1R), yellow (ASIP), silver (MITF), lavender (MLPH), roux (TYRP1), imperfect albinism (SLC45A2) and rusty. As compared with wild-type quail, all mutations but extended brown decreased total melanins. The largest decrease was observed in quail with one of the dilution mutations at TYRP1, MLPH or SLCA45A2. No difference in eumelanins was found between the 10 plumage colours. Despite visible colour differences, homozygous and heterozygous mutants at MITF, or the two imperfect albino (white) and cinnamon (pale yellow) alleles at SLC45A2, could not be differentiated on the basis of melanins. In contrast, the two white phenotypes caused by mutations at MITF and SLC45A2, or the two reddish plumage colours caused by the roux and rusty non-allelic mutations had different total melanin contents. The results showed that rusty was not likely to be a dilution mutation. PMID:19496774

Minvielle, F; Cecchi, T; Passamonti, P; Gourichon, D; Renieri, C



Chiral colour and axigluons  

SciTech Connect

The authors studies the phenomenological implications of the Chiral Colour model which allow him to derive experimental bounds on the axigluon mass or to predict deviations from the Standard Model. After a short introduction to the theory, the author examines the way it modifies the standard decay of quarkonium. Comparison with the observed lifetime of the upsilon allows him to exclude the existence of axigluons lighter than 9 GeV. (Others have since extended the work and were able to increase this limit to 25 GeV.) He then studies the Chiral Colour contribution to the hadronic cross-section in the electron-positron scattering and derive a conservative lower bound of 50 GeV for the axigluon mass. Finally, he predicts observable enhancements of the lifetime and rare decay channels of the Z{sup O} in the presence of light axigluons.

Cuypers, F.



Comparison of marine algae (Spirulina platensis) and synthetic pigment in enhancing egg yolk colour of laying hens.  


The objective of this experiment was to determine the effects of dietary marine algae (Spirulina platensis) on egg yolk colour, and compare the effectiveness of Spirulina and synthetic pigment in enhancing egg yolk colour of laying hens fed on a wheat-based diet. In total, 160 Hy-line W36 laying hens of 63 weeks of age were studied by dividing them into 5 groups, 32 birds in each. Except for the control group (based on wheat and soyabean meal), the feed for three other groups contained 1·5, 2·0 and 2·5% of Spirulina; while one group contained synthetic pigments (BASF Lucantin® yellow: 30?mg/kg, and BASF Lucantin® red: 35?mg/kg). Egg production, feed intake, feed conversion ratio (FCR), egg weight and egg yolk colour were determined. A significant increase in egg yolk colour was observed in the treatments that received the Spirulina and synthetic pigment, compared with the control diet. There were no significant differences between the treatments with 2·5% Spirulina and synthetic pigment in enhancing egg yolk colour. Finally, the results indicated that the diet containing 2·5% Spirulina could be as effective as the diet with synthetic pigment in producing an agreeable egg yolk colour. PMID:22029786

Zahroojian, N; Moravej, H; Shivazad, M



Coloured Petri Nets  

Microsoft Academic Search

This paper describes a Petri net model, called Coloured Petri nets (CP-nets), where information is attached to each token.\\u000a The information can be inspected and modified when a transition fires. For most applications, this generalization of ordinary\\u000a Petri nets allows the user to make more manageable descriptions, due to the fact that equal subnets can be folded into each\\u000a other,

Kurt Jensen



Spatio-temporal colour correction of strongly degraded movies  

NASA Astrophysics Data System (ADS)

The archives of motion pictures represent an important part of precious cultural heritage. Unfortunately, these cinematography collections are vulnerable to different distortions such as colour fading which is beyond the capability of photochemical restoration process. Spatial colour algorithms-Retinex and ACE provide helpful tool in restoring strongly degraded colour films but, there are some challenges associated with these algorithms. We present an automatic colour correction technique for digital colour restoration of strongly degraded movie material. The method is based upon the existing STRESS algorithm. In order to cope with the problem of highly correlated colour channels, we implemented a preprocessing step in which saturation enhancement is performed in a PCA space. Spatial colour algorithms tend to emphasize all details in the images, including dust and scratches. Surprisingly, we found that the presence of these defects does not affect the behaviour of the colour correction algorithm. Although the STRESS algorithm is already in itself more efficient than traditional spatial colour algorithms, it is still computationally expensive. To speed it up further, we went beyond the spatial domain of the frames and extended the algorithm to the temporal domain. This way, we were able to achieve an 80 percent reduction of the computational time compared to processing every single frame individually. We performed two user experiments and found that the visual quality of the resulting frames was significantly better than with existing methods. Thus, our method outperforms the existing ones in terms of both visual quality and computational efficiency.

Islam, A. B. M. Tariqul; Farup, Ivar



Effects of gamma irradiation on total polyphenols, radical scavenging activities and decolourization of Nelumbo nucifera extracts  

NASA Astrophysics Data System (ADS)

The ethanolic leaf extract of Nelumbo nucifera (NC) was exposed to ?-irradiation, and its antioxidant activities, total polyphenols and colour characteristics were studied to discern its potential ability as a food or cosmetic materials. The results demonstrated that the radical scavenging activities and total polyphenols of the ?-irradiated leaf extract of NC were not observed to be significantly different. However, ?-irradiation significantly increased the Hunter colour L*-value at doses of 20 and 50 kGy, while the Hunter colour b*-values were decreased under the same conditions.

Jeong, Il Yun; Lee, Hyo Jung; Park, Yong Dae; Jin, Chang Hyun; Choi, Dae Seong; Byun, Myung Woo



Total polyphenolic (flavonoids) content and antioxidant capacity of different Ziziphora clinopodioides Lam. extracts  

PubMed Central

Objective: This paper investigates the total polyphenolic and flavonoid content as well as the antioxidant activity of Ziziphora clinopodioides Lam. extracts of different polarity. Materials and Methods: The total polyphenolic content was analysed using the Folin–Ciocalteu method. Total flavonoid content analysis was performed using the colorimetric method. Results: The total polyphenolic content of Z. clinopodioides is concentrated in parts of ethyl acetate (19.27%), chloroform (4.99%) and n-butanol extracts (3.94%) containing a small amount of the total polyphenolic content. The petroleum ether (0.23%) and ethanol extracts (1.64%) contain almost no polyphenolic content. The total flavonoid content of Z. clinopodioides is concentrated in parts of ethyl acetate (65.61%), chloroform (14.36%) and n-butanol extracts (10.76%) containing a small amount of the total polyphenolic content. The Z. clinopodioides Lam. ethyl acetate extract exhibits a good antioxidant activity. Conclusion: Ethyl acetate extracts contain a large number of polyphenolic compounds (19.27%) and flavonoids (65.61%) owing to good antioxidant capacity.

Tian, Shuge; Shi, Yang; Zhou, Xiaoying; Ge, Liang; Upur, Halmuart



Another look at category effects on colour perception and their left hemispheric lateralisation: no evidence from a colour identification task.  


The present study aimed to replicate category effects on colour perception and their lateralisation to the left cerebral hemisphere (LH). Previous evidence for lateralisation of colour category effects has been obtained with tasks where a differently coloured target was searched within a display and participants reported the lateral location of the target. However, a left/right spatial judgment may yield LH-laterality effects per se. Thus, we employed an identification task that does not require a spatial judgment and used the same colour set that previously revealed LH-lateralised category effects. The identification task was better performed with between-category colours than with within-category task both in terms of accuracy and latency, but such category effects were bilateral or RH-lateralised, and no evidence was found for LH-laterality effects. The accuracy scores, moreover, indicated that the category effects derived from low sensitivities for within-blue colours and did not reflect the effects of categorical structures on colour perception. Furthermore, the classic "category effects" were observed in participants' response biases, instead of sensitivities. The present results argue against both the LH-lateralised category effects on colour perception and the existence of colour category effects per se. PMID:24430783

Suegami, Takashi; Aminihajibashi, Samira; Laeng, Bruno



A total variation diminishing finite difference algorithm for sonic boom propagation models  

NASA Technical Reports Server (NTRS)

It is difficult to accurately model the rise phases of sonic boom waveforms with traditional finite difference algorithms because of finite difference phase dispersion. This paper introduces the concept of a total variation diminishing (TVD) finite difference method as a tool for accurately modeling the rise phases of sonic booms. A standard second order finite difference algorithm and its TVD modified counterpart are both applied to the one-way propagation of a square pulse. The TVD method clearly outperforms the non-TVD method, showing great potential as a new computational tool in the analysis of sonic boom propagation.

Sparrow, Victor W.



Genetic analyses of the human eye colours using a novel objective method for eye colour classification.  


In this study, we present a new objective method for measuring the eye colour on a continuous scale that allows researchers to associate genetic markers with different shades of eye colour. With the use of the custom designed software Digital Iris Analysis Tool (DIAT), the iris was automatically identified and extracted from high resolution digital images. DIAT was made user friendly with a graphical user interface. The software counted the number of blue and brown pixels in the iris image and calculated a Pixel Index of the Eye (PIE-score) that described the eye colour quantitatively. The PIE-score ranged from -1 to 1 (brown to blue). The software eliminated the need for user based interpretation and qualitative eye colour categories. In 94% (570) of 605 analyzed eye images, the iris region was successfully extracted and a PIE-score was calculated. A very high correlation between the PIE-score and the human perception of eye colour was observed. The correlations between the PIE-scores and the six IrisPlex SNPs (HERC2 rs12913832, OCA2 rs1800407, SLC24A4 rs12896399, TYR rs1393350, SLC45A2 rs16891982 and IRF4 rs12203592) were analyzed in 570 individuals. Significant differences (p<10(-6)) in the PIE-scores of the individuals typed as HERC2 rs12913832 G (PIE=0.99) and rs12913832 GA (PIE=-0.71) or A (PIE=-0.87) were observed. We adjusted for the effect of HERC2 rs12913832 and showed that the quantitative PIE-scores were significantly associated with SNPs with minor effects (OCA2 rs1800407, SLC24A4 rs12896399 and TYR rs1393350) on the eye colour. We evaluated the two published prediction models for eye colour (IrisPlex [1] and Snipper[2]) and compared the predictions with the PIE-scores. We found good concordance with the prediction from individuals typed as HERC2 rs12913832 G. However, both methods had difficulties in categorizing individuals typed as HERC2 rs12913832 GA because of the large variation in eye colour in HERC2 rs12913832 GA individuals. With the use of the DIAT software and the PIE-score, it will be possible to automatically compare the iris colour of large numbers of iris images obtained by different studies and to perform large meta-studies that may reveal loci with small effects on the eye colour. PMID:23948321

Andersen, Jeppe D; Johansen, Peter; Harder, Stine; Christoffersen, Susanne R; Delgado, Mikaela C; Henriksen, Sarah T; Nielsen, Mette M; Sørensen, Erik; Ullum, Henrik; Hansen, Thomas; Dahl, Anders L; Paulsen, Rasmus R; Børsting, Claus; Morling, Niels



Iris Recognition System Using Combined Colour Statistics  

Microsoft Academic Search

This paper proposes a high performance iris recognition system based on the probability distribution functions (PDF) of pixels in different colour channels. The PDFs of the segmented iris images are used as statistical feature vectors for the recognition of irises by minimizing the Kullback-Leibler distance (KLD) between the PDF of a given iris and the PDFs of irises in the

Hasan Demirel; G. Anbarjafari



New Evidence for Infant Colour Categories  

ERIC Educational Resources Information Center

Bornstein, Kessen, and Weiskopf (1976) reported that pre-linguistic infants perceive colour categorically for primary boundaries: Following habituation, dishabituation only occurred if the test stimulus was from a different adult category to the original. Here, we replicated this important study and extended it to include secondary boundaries,…

Franklin, Anna; Davies, Ian R. L.



Dual-colour imaging with GFP variants  

Microsoft Academic Search

Green fluorescent protein (GFP) has become an important tool in cell biology and is widely used as a reporter for imaging intracellular proteins and structures in live cells. Recently, spectral variants of GFP with red- and blue-shifted fluorescence emissions have been characterized, opening the possibility of double labelling with two different-coloured GFP fusion proteins. This article reviews recent advances in

Jan Ellenberg; Jennifer Lippincott-Schwartz; John F. Presley



Colour misbinding during motion rivalry  

PubMed Central

When two dissimilar colours are displayed to the two eyes at overlapping retinal locations, binocular rivalry typically results: a fluctuating struggle for perceptual dominance of each eye's stimulus. We found instead that isoluminant counter-rotating patterns consisting of coloured and achromatic portions can promote an illusory colour ‘misbinding’, where the colours from both eyes were perceived within a single rotating pattern. The achromatic portion of one rotating pattern thus appeared to take on the colour of the other, oppositely rotating pattern. The results suggest that the neural mechanisms of colour binding can operate even while representations of the same patterns' motions are undergoing rivalry, and support the idea that rivalry can occur in isolation within the motion system.

Maloney, Ryan T.; Lam, Sarah K.; Clifford, Colin W. G.



Camouflage, communication and thermoregulation: lessons from colour changing organisms  

PubMed Central

Organisms capable of rapid physiological colour change have become model taxa in the study of camouflage because they are able to respond dynamically to the changes in their visual environment. Here, we briefly review the ways in which studies of colour changing organisms have contributed to our understanding of camouflage and highlight some unique opportunities they present. First, from a proximate perspective, comparison of visual cues triggering camouflage responses and the visual perception mechanisms involved can provide insight into general visual processing rules. Second, colour changing animals can potentially tailor their camouflage response not only to different backgrounds but also to multiple predators with different visual capabilities. We present new data showing that such facultative crypsis may be widespread in at least one group, the dwarf chameleons. From an ultimate perspective, we argue that colour changing organisms are ideally suited to experimental and comparative studies of evolutionary interactions between the three primary functions of animal colour patterns: camouflage; communication; and thermoregulation.

Stuart-Fox, Devi; Moussalli, Adnan



The lavender plumage colour in Japanese quail is associated with a complex mutation in the region of MLPH that is related to differences in growth, feed consumption and body temperature  

PubMed Central

Background The lavender phenotype in quail is a dilution of both eumelanin and phaeomelanin in feathers that produces a blue-grey colour on a wild-type feather pattern background. It has been previously demonstrated by intergeneric hybridization that the lavender mutation in quail is homologous to the same phenotype in chicken, which is caused by a single base-pair change in exon 1 of MLPH. Results In this study, we have shown that a mutation of MLPH is also associated with feather colour dilution in quail, but that the mutational event is extremely different. In this species, the lavender phenotype is associated with a non-lethal complex mutation involving three consecutive overlapping chromosomal changes (two inversions and one deletion) that have consequences on the genomic organization of four genes (MLPH and the neighbouring PRLH, RAB17 and LRRFIP1). The deletion of PRLH has no effect on the level of circulating prolactin. Lavender birds have lighter body weight, lower body temperature and increased feed consumption and residual feed intake than wild-type plumage quail, indicating that this complex mutation is affecting the metabolism and the regulation of homeothermy. Conclusions An extensive overlapping chromosome rearrangement was associated with a non-pathological Mendelian trait and minor, non deleterious effects in the lavender Japanese quail which is a natural knockout for PRLH.



Colour thresholding and objective quantification in bioimaging.  


Computer imaging is rapidly becoming an indispensable tool for the quantification of variables in research and medicine. Whilst its use in medicine has largely been limited to qualitative observations, imaging in applied basic sciences, medical research and biotechnology demands objective quantification of the variables in question. In black and white densitometry (0-256 levels of intensity) the separation of subtle differences between closely related hues from stains is sometimes very difficult. True-colour and real-time video microscopy analysis offer choices not previously available with monochrome systems. In this paper we demonstrate the usefulness of colour thresholding, which has so far proven indispensable for proper objective quantification of the products of histochemical reactions and/or subtle differences in tissue and cells. In addition, we provide interested, but untrained readers with basic information that may assist decisions regarding the most suitable set-up for a project under consideration. Data from projects in progress at Tulane are shown to illustrate the advantage of colour thresholding over monochrome densitometry and for objective quantification of subtle colour differences between experimental and control samples. PMID:1527795

Fermin, C D; Gerber, M A; Torre-Bueno, J R



Differences between recalculated and original Dobson total ozone data from Hradec Kralove, Czechoslovakia, 1962-1990  

NASA Technical Reports Server (NTRS)

Backward reevaluation of long-term total ozone measurements from the Solar and Ozone Observatory of Czech Hydrometeorological Institute at Hradec Kralove, Czechoslovakia, was performed for the period 1962-1990. The homogenization was carried out with respect to the calibration level of the World Primary Standard Spectrophotometer No. 83 - WPSS by means of day-by-day recalculations of more than 25,000 individual measurements using the R-N tables reconstructed after international comparisons and regular standard lamp tests of the Dobson spectrophotometer No. 74. The results showed significant differences among the recalculated data and those original ones published in the bulletins Ozone Data for the World. In the period 1962-1979 they reached 10-19 D.U. (3.0-5.5%) for annual averages and even 26 D.U. (7.0%) for monthly averages of total ozone. Such differences exceed several times accuracy of measuring and can significantly influence character of trends of total ozone in Central Europe. Therefore the results from Hradec Kralove support the calls for reevaluation of all historical Dobson total ozone data sets at individual stations of Global Ozone Observing System.

Vanicek, Karel



Exploring consumers' product-specific colour meanings  

Microsoft Academic Search

Purpose – The impact of colour is acknowledged, yet empirical studies on colours with marketing implications are rare. The paper seeks to advance our understanding of the role of package colours in consumers' product experiences by studying the relationship between colour meanings and product. It also aims at offering insights into the meanings associated with colours in a product context.

Hannele Kauppinen-Räisänen; Harri T. Luomala



Odour and colour polymorphism in the food-deceptive orchid Dactylorhiza romana  

Microsoft Academic Search

The food deceptive orchid, Dactylorhiza romana (Sebastiani) Soó exhibits a colour polymorphism with yellow, red, and intermediate orange morphs. In this study we tested\\u000a if floral odour differed among the three distinct colour morphs. We identified 23 odour compounds in D. romana, and all of them occurred in the three colour morphs. Monoterpenes dominated the floral scent. On the basis

C. C. Salzmann; F. P. Schiestl



Digital colour management system for colour parameters reconstruction  

NASA Astrophysics Data System (ADS)

Digital Colour Management System (DCMS) and its application to new adaptive camouflage system are presented in this paper. The DCMS is a digital colour rendering method which would allow for transformation of a real image into a set of colour pixels displayed on a computer monitor. Consequently, it can analyse pixels' colour which comprise images of the environment such as desert, semi-desert, jungle, farmland or rocky mountain in order to prepare an adaptive camouflage pattern most suited for the terrain. This system is described in present work as well as the use the subtractive colours mixing method to construct the real time colour changing electrochromic window/pixel (ECD) for camouflage purpose. The ECD with glass/ITO/Prussian Blue(PB)/electrolyte/CeO2-TiO2/ITO/glass configuration was assembled and characterized. The ECD switched between green and yellow after +/-1.5 V application and the colours have been controlled by Digital Colour Management System and described by CIE LAB parameters.

Grudzinski, Karol; Lasmanowicz, Piotr; Assis, Lucas M. N.; Pawlicka, Agnieszka; Januszko, Adam



Equivalent total doses for different fractionation schemes, based on the linear quadratic model  

SciTech Connect

A majority of patients receiving radical radiation therapy are treated with 1.8-2.0-Gy fractions, a dose that has evolved from clinical experience. However, other fractionation schemes can be advantageous. When fractionation is altered, the total dose prescribed should lead to equivalent or higher tumor control with the same or less tissue toxicity. To facilitate the use of different fractionation schemes, the authors compiled tables for equivalent biologic doses for late toxicity in normal tissues and tumoricidal doses for epithelial tumors, for various fraction sizes. The linear quadratic model according to Fowler was used. It is shown how these tables should be modified for proliferation of tumors during the course of radiation therapy. The tables make the use of different fractionation schemes easy. They also allow adjustment of total dose if fractionation needs to be changed during the course of treatment.

Muller-Runkel, R.; Vijayakumar, S. (St. Margaret Hospital and Health Centers, Hammond, IN (USA))



The role of meaning in grapheme-colour synaesthesia.  


When the synaesthete, J, is shown black graphemes, in addition to perceiving the black digits or letters she also experiences highly specific colours that overlay the graphemes (e.g., 5 is pink, S is green). We used ambiguous graphemes in a Stroop-type task to show that the exact same forms (e.g., 5) can elicit different synaesthetic colours depending on whether they are interpreted as digits or letters. J was shown strings of black digits (e.g., 3 4 5 6 7) or words (e.g., M U S I C for 1 sec. All but one of the graphemes then disappeared and the remaining grapheme changed to a colour that J had to name as quickly as possible. The key trials involved coloured graphemes that were ambiguous (e.g., the 5 in the strings above could be interpreted either as a digit or as a letter). On congruent trials, the colour of the ambiguous target grapheme was the same as J's photism for the digit or letter interpretations of the grapheme. On incongruent trials, the colours of the ambiguous target graphemes were different than the colours of J's photisms for the digit or letter interpretations of the graphemes. On digit-context incongruent trials, the ambiguous graphemes were presented in J's colour for the letter-interpretations of the graphemes, whereas on letter-context incongruent trials, the ambiguous graphemes were presented in J's colours for the digit-interpretations of the graphemes. Thus the same ambiguous grapheme (e.g., a pink 5) served as a congruent stimulus in one context and an incongruent stimulus in another context. J's response times showed that ambiguous graphemes elicited different photisms depending on whether they were interpreted as digits or letters. This finding suggests that it is not the form but the meaning of graphemes (whether they are interpreted as digits or letters) that determines the colours of synaesthetic photisms. PMID:16683498

Dixon, Mike J; Smilek, Daniel; Duffy, Patricia L; Zanna, Mark P; Merikle, Philip M



Behavioural evidence of colour vision in free flying stingless bees.  


Colour vision was first demonstrated with behavioural experiments in honeybees 100 years ago. Since that time a wealth of quality physiological data has shown a highly conserved set of trichromatic colour receptors in most bee species. Despite the subsequent wealth of behavioural research on honeybees and bumblebees, there currently is a relative dearth of data on stingless bees, which are the largest tribe of the eusocial bees comprising of more than 600 species. In our first experiment we tested Trigona cf. fuscipennis, a stingless bee species from Costa Rica in a field setting using the von Frisch method and show functional colour vision. In a second experiment with these bees, we use a simultaneous colour discrimination test designed for honeybees to enable a comparative analysis of relative colour discrimination. In a third experiment, we test in laboratory conditions Tetragonula carbonaria, an Australian stingless bee species using a similar simultaneous colour discrimination test. Both stingless bee species show relatively poorer colour discrimination compared to honeybees and bumblebees; and we discuss the value of being able to use these behavioural methods to efficiently extend our current knowledge of colour vision and discrimination in different bee species. PMID:24519371

Spaethe, J; Streinzer, M; Eckert, J; May, S; Dyer, A G



The development of artists' novel colour palettes for inkjet printing  

NASA Astrophysics Data System (ADS)

In this changing environment in which the artist and designer has access to a wide range of digital imaging tools and technologies, that on first glance, are dedicated to the creation of colour mixtures, why is the digital interface and colour outcome often disappointing? It appears that hardware, software tools and methods for digital printing are not necessarily suited to the specific requirements of the artist. In fact, they are too generalised to obtain a high degree of quality and too inflexible to allow artists to obtain precision and predictability. Is it possible for an artist to mix and print a colour that captures their creative imagination? The motivation for this research is based on how artists mix and print colour by traditional means (painting and printmaking) and how these differ from colour picker tools, slider bars and methods developed for digital printing, and whether it is possible to incorporate both? The paper provides a brief historical background to artists who have developed colour systems to assist their particular colour choices. Based on existing hardware and software, the paper suggests alternative approaches to colour selection, demonstrates methods for the creation of novel inkjet printed palettes, and how these can be visualised and compared.

Parraman, Carinna



Colour and AOX removal from pulping effluents by algae  

Microsoft Academic Search

A mixed culture of algae was used to treat pulping mill effluent in terms of removing both colour and adsorbably organic\\u000a halides (AOX). The removal of AOX from pulping effluent increased with increasing initial colour value of the effluent. However,\\u000a for the total mill effluent (composed of both pulping and bleaching effluents), AOX removal was found to be independent of

F. B. Dilek; H. M. Taplamacioglu; E. Tarlan



Artist's colour rendering of HDR scenes in 3D Mondrian colour-constancy experiments  

NASA Astrophysics Data System (ADS)

The presentation provides an update on ongoing research using three-dimensional Colour Mondrians. Two still life arrangements comprising hand-painted coloured blocks of 11 different colours were subjected to two different lighting conditions of a nearly uniform light and directed spotlights. The three-dimensional nature of these test targets adds shadows and multiple reflections, not found in flat Mondrian targets. Working from exactly the same pair of scenes, an author painted them using watercolour inks and paints to recreate both LDR and HDR Mondrians on paper. This provided us with a second set of appearance measurements of both scenes. Here we measured appearances by measuring reflectances of the artist's rendering. Land's Colour Mondrian extended colour constancy from a pixel to a complex scene. Since it used a planar array in uniform illumination, it did not measure the appearances of real life 3-D scenes in non-uniform illumination. The experiments in this paper, by simultaneously studying LDR and HDR renditions of the same array of reflectances, extend Land's Mondrian towards real scenes in non-uniform illumination. The results show that the appearances of many areas in complex scenes do not correlate with reflectance.

Parraman, Carinna E.; McCann, John J.; Rizzi, Alessandro



Colour Vision and Colour Vision Theories  

Microsoft Academic Search

PROF. PEDDIE states in his letter in NATURE of September 8, p. 362, that the facts that I have given as totally opposed to the trichromatic theory can be explained by it. If he will show how this can be done I can then deal with his explanations. Directly the trichromatic theory is put in a definite form its failure

F. W. Edridge-Green



CIE Colorimetry and Colour Displays  

Microsoft Academic Search

CIE colorimetry was standardised 65 years ago to describe colorimetric properties of signal lights. The first real application of CIE colorimetry occurred, however, in the textile and coating industries to describe colour matches between sample and reference. Thus also the experiments conducted to achieve a uniform colour scale diagram were performed by using material samples usually illuminated by a daylight

J Schanda



The phylogenetic significance of colour patterns in marine teleost larvae  

PubMed Central

Ichthyologists, natural-history artists, and tropical-fish aquarists have described, illustrated, or photographed colour patterns in adult marine fishes for centuries, but colour patterns in marine fish larvae have largely been neglected. Yet the pelagic larval stages of many marine fishes exhibit subtle to striking, ephemeral patterns of chromatophores that warrant investigation into their potential taxonomic and phylogenetic significance. Colour patterns in larvae of over 200 species of marine teleosts, primarily from the western Caribbean, were examined from digital colour photographs, and their potential utility in elucidating evolutionary relationships at various taxonomic levels was assessed. Larvae of relatively few basal marine teleosts exhibit erythrophores, xanthophores, or iridophores (i.e. nonmelanistic chromatophores), but one or more of those types of chromatophores are visible in larvae of many basal marine neoteleosts and nearly all marine percomorphs. Whether or not the presence of nonmelanistic chromatophores in pelagic marine larvae diagnoses any major teleost taxonomic group cannot be determined based on the preliminary survey conducted, but there is a trend toward increased colour from elopomorphs to percomorphs. Within percomorphs, patterns of nonmelanistic chromatophores may help resolve or contribute evidence to existing hypotheses of relationships at multiple levels of classification. Mugilid and some beloniform larvae share a unique ontogenetic transformation of colour pattern that lends support to the hypothesis of a close relationship between them. Larvae of some tetraodontiforms and lophiiforms are strikingly similar in having the trunk enclosed in an inflated sac covered with xanthophores, a character that may help resolve the relationships of these enigmatic taxa. Colour patterns in percomorph larvae also appear to diagnose certain groups at the interfamilial, familial, intergeneric, and generic levels. Slight differences in generic colour patterns, including whether the pattern comprises xanthophores or erythrophores, often distinguish species. The homology, ontogeny, and possible functional significance of colour patterns in larvae are discussed. Considerably more investigation of larval colour patterns in marine teleosts is needed to assess fully their value in phylogenetic reconstruction.

Baldwin, Carole C



Comparison of ionospheric total electron content measured using the difference Doppler and incoherent scatter methods  

NASA Astrophysics Data System (ADS)

A two-station difference Doppler method has been used to determine latitudinal profiles of the ionospheric total electron content in the auroral and subauroral region. The method is applied to data from a chain of three receiving stations situated along the same magnetic meridian. The results are compared with latitudinal electron content profiles calculated from simultaneous EISCAT observations. Data obtained from these two experiments are found to be in excellent agreement which confirms that the two-station method is useful at high latitudes. The Russian receiver chain is considered to give valuable information to EISCAT studies.

Cherniakov, S. M.; Tereshchenko, E. D.; Brunelli, B. E.; Nygren, T.



Antioxidant activity and total phenolics in selected cereal grains and their different morphological fractions.  


The purpose of this study was to examine the antioxidant properties of water and 80% methanolic extracts of cereal grains and their different morphological fractions. Wheat (Triticum aestivum L.) cv. Almari and cv. Henika, barley (Hordeum vulgare L.) cv. Gregor and cv. Mobek, rye (Secale cereale L.) cv. Da?kowskie Zlote, oat (Avena sativa L.) cv. Slawko and buckwheat (Fagopyrum esculentum Moench) cv. Kora were used. PC (L-alpha-phosphatidylcholine) liposome system and spectrophotometric assay of total antioxidant activity (TAA) were used to evaluate the antioxidative activity of extracts. Among the water extracts, only the one prepared from buckwheat exhibited antioxidant activity at the concentration analyzed. The following hierarchy of antioxidant activity was provided for 80% methanolic extracts originated from whole grain: buckwheat > barley > oat > wheat congruent with rye. The antioxidant activity was observed in extract prepared from separated parts of buckwheat and barley. In respect to hulls, the antioxidant hierarchy was as follows: buckwheat > oat > barley. The correlation coefficient between total phenolic compounds and total antioxidative activity of the extracts was -0.35 for water extracts and 0.96, 0.99, 0.80, and 0.99 for 80% methanolic extracts originated from whole grains, hulls, pericarb with testa fractions and endosperm with embryo fractions, respectively. PMID:10888490

Zieli?ski, H; Koz?owska, H



Modelling the colour of a coated rough-steel surface  

NASA Astrophysics Data System (ADS)

A metal has a typical grey "metallic" look. Different colours can appear when the metallic surface is covered with a thin transparent layer. This is of course the result of interference, and consequently the colour depends on the optical thickness of the layer. Experimental observations can be completely predicted by theoretical modelling. Using the Fresnel equations the colour can be calculated within excellent agreement of the experimental observations. Fresnel, of course, assumes perfectly flat surfaces. Roughness complicates matters: the optical path within the coating no longer depends on the local thickness of the coating only, but also on the angle of scattering at the underlying metal, both varying from point to point. In this presentation we describe how the roughness can be taken into account in predicting the colour. The scattered light was calculated using the "Modeled Integrated Scattering Tool", a computer program developed at the "National Institute of Standards and Technology" (USA). The non-uniformity of the coatings was taken into account by considering different coatings thicknesses. The resulting colour is calculated by taking the average of the obtained reflections. Finally the colours were measured with a spectrophotometer. It turned out that the modelled and the measured colours agree very well, confirming the validity of the used model.

Goossens, V.; Stijns, E.; van Gils, S.; Finsy, R.; Terryn, H.



Iodide-assisted total lead measurement and determination of different lead fractions in drinking water samples.  


Lead and its compounds are toxic and can harm human health, especially the intelligence development in children. Accurate measurement of total lead present in drinking water is crucial in determining the extent of lead contamination and human exposure due to drinking water consumption. The USEPA method for total lead measurement (no. 200.8) is often used to analyze lead levels in drinking water. However, in the presence of high concentration of the tetravalent lead corrosion product PbO(2), the USEPA method was not able to fully recover particulate lead due to incomplete dissolution of PbO(2) particles during strong acid digestion. In this study, a new procedure that integrates membrane separation, iodometric PbO(2) measurement, strong acid digestion and ICP-MS measurement was proposed and evaluated for accurate total lead measurement and quantification of different lead fractions including soluble Pb(2+), particulate Pb(II) carbonate and PbO(2) in drinking water samples. The proposed procedure was evaluated using drinking water reconstituted with spiked Pb(2+), spiked particulate Pb(II) carbonate and in situ formed or spiked PbO(2). Recovery tests showed that the proposed procedure and the USEPA method can achieve 93-112% and 86-103% recoveries respectively for samples containing low PbO(2) concentrations (0.018-0.076 mg Pb per L). For samples containing higher concentrations of PbO(2) (0.089-1.316 mg Pb per L), the USEPA method failed to meet the recovery requirement for total lead (85-115%) while the proposed method can achieve satisfactory recoveries (91-111%) and differentiate the soluble Pb(2+), particulate Pb(II) carbonate and PbO(2). PMID:22622848

Zhang, Yuanyuan; Ng, Ding-Quan; Lin, Yi-Pin



The role of humans in facilitating and sustaining coat colour variation in domestic animals.  


Though the process of domestication results in a wide variety of novel phenotypic and behavioural traits, coat colour variation is one of the few characteristics that distinguishes all domestic animals from their wild progenitors. A number of recent reviews have discussed and synthesised the hundreds of genes known to underlie specific coat colour patterns in a wide range of domestic animals. This review expands upon those studies by asking how what is known about the causative mutations associated with variable coat colours, can be used to address three specific questions related to the appearance of non wild-type coat colours in domestic animals. Firstly, is it possible that coat colour variation resulted as a by-product of an initial selection for tameness during the early phases of domestication? Secondly, how soon after the process began did domestic animals display coat colour variation? Lastly, what evidence is there that intentional human selection, rather than drift, is primarily responsible for the wide range of modern coat colours? By considering the presence and absence of coat colour genes within the context of the different pathways animals travelled from wild to captive populations, we conclude that coat colour variability was probably not a pleiotropic effect of the selection for tameness, that coat colours most likely appeared very soon after the domestication process began, and that humans have been actively selecting for colour novelty and thus allowing for the proliferation of new mutations in coat colour genes. PMID:23567209

Linderholm, Anna; Larson, Greger



Optimization of instrumental colour analysis in dry-cured ham.  


Colour of dry cured ham was measured by instrumental techniques in order to determine the optimum measurement index. Five different colour systems were used: CIE L(?)a(?)b(?), Hunter Lab, CIE L(?)u(?)v(?), xyY and XYZ, each with illuminants D65, C and A, and with both 10 and 2° observer angles. Measurements were taken in both Semimembranosus (SM) and Biceps femoris (BF) muscles. Hunter Lab system with illuminant A gave the most reproducible results within muscles for the three colour parameters evaluated. A further comparison of results obtained with 10 and 2° observer angles of Hunter Lab with illuminant A showed there were no significant differences between the angles. Significant differences between results from SM and BF muscles were found in all the hams, the BF always showing higher values than SM for every colour parameter. PMID:22062379

García-Esteban, Marta; Ansorena, Diana; Gimeno, Olga; Astiasarán, Iciar



Optimal colour quality of LED clusters based on memory colours.  


The spectral power distributions of tri- and tetrachromatic clusters of Light-Emitting-Diodes, composed of simulated and commercially available LEDs, were optimized with a genetic algorithm to maximize the luminous efficacy of radiation and the colour quality as assessed by the memory colour quality metric developed by the authors. The trade-off of the colour quality as assessed by the memory colour metric and the luminous efficacy of radiation was investigated by calculating the Pareto optimal front using the NSGA-II genetic algorithm. Optimal peak wavelengths and spectral widths of the LEDs were derived, and over half of them were found to be close to Thornton's prime colours. The Pareto optimal fronts of real LED clusters were always found to be smaller than those of the simulated clusters. The effect of binning on designing a real LED cluster was investigated and was found to be quite large. Finally, a real LED cluster of commercially available AlGaInP, InGaN and phosphor white LEDs was optimized to obtain a higher score on memory colour quality scale than its corresponding CIE reference illuminant. PMID:21451716

Smet, Kevin; Ryckaert, Wouter R; Pointer, Michael R; Deconinck, Geert; Hanselaer, Peter



Are hip hemiarthroplasty and total hip arthroplasty infections different entities? The importance of hip fractures.  


Hip hemiarthroplasty (HHA) and total hip arthroplasty (THA) infections are usually considered as one entity; however, they may show important differences. We analyze these differences, as well as predictors of treatment failure (TF) and poor functional status among patients with prosthetic hip infections (PHIs). A multicenter cohort study of consecutive patients with PHIs was performed. The main outcome variable was TF after the first surgical treatment performed to treat the infection. Multivariate analysis was used to identify predictors of TF. A total of 127 patients with PHI were included (43 HHA, 84 THA). Patients with HHA infections were more frequently women (88 % vs. 54 %; p?differences in epidemiology, clinical features, and outcome. Although patients with HHA infections had a higher risk of TF, this was related to the reason for hip implant: a hip fracture. Success of the initial management of infection is a predictor of better clinical and functional outcome. PMID:24671411

Del Toro, M D; Nieto, I; Guerrero, F; Corzo, J; Del Arco, A; Palomino, J; Nuño, E; Lomas, J M; Natera, C; Fajardo, J M; Delgado, J; Torres-Tortosa, M; Romero, A; Martín-Rico, P; Muniain, M A; Rodríguez-Baño, J



Fine colour discrimination requires differential conditioning in bumblebees  

NASA Astrophysics Data System (ADS)

Accurate recognition requires that visual systems must be able to discriminate between target and distractor stimuli. Flowers are learned and recognised by bees using visual cues including colour and shape. We investigated whether bees were able to learn to discriminate between colours differently depending upon absolute or differential conditioning. For absolute conditioning bees were rewarded with sucrose solution for visits to target flowers. When distractor stimuli were subsequently presented, a high level of discrimination was observed if there was a perceptually large colour distance separating distractors and targets, but for a perceptually small colour distance the bees generalised and did not discriminate between stimuli. When provided with differential conditioning where both target and distractors were present, the bees learnt to discriminate stimuli separated by a perceptually small colour distance. This shows that for bees to learn fine colour discrimination tasks it is important to use differential conditioning. The findings are discussed within the context of the necessity for plants to produce distinctive flower colours.

Dyer, Adrian G.; Chittka, Lars


Colour constancy across the life span: evidence for compensatory mechanisms.  


It is well known that the peripheral visual system declines with age: the yellowing of the lens causes a selective reduction of short-wavelength light and sensitivity losses occur in the cone receptor mechanisms. At the same time, our subjective experience of colour does not change with age. The main purpose of this large-scale study (n?=?185) covering a wide age range of colour-normal observers (18-75 years of age) was to assess the extent to which the human visual system is able to compensate for the changes in the optical media and at which level of processing this compensation is likely to occur. We report two main results: (1) Supra-threshold parafoveal colour perception remains largely unaffected by the age-related changes in the optical media (yellowing of the lens) whereas our ability to discriminate between small colour differences is compromised with an increase in age. (2) Significant changes in colour appearance are only found for unique green settings under daylight viewing condition which is consistent with the idea that the yellow-blue mechanism is most affected by an increase in age due to selective attenuation of short-wavelength light. The data on the invariance of hue perception, in conjunction with the age-related decline in chromatic sensitivity, provides evidence for compensatory mechanisms that enable colour-normal human observers a large degree of colour constancy across the life span. These compensatory mechanisms are likely to originate at cortical sites. PMID:23667689

Wuerger, Sophie



Differences in metal ion release following cobalt-chromium and oxidized zirconium total knee arthroplasty.  


Ions are released from all metals after implantation in the body through processes of corrosive and mechanical wear. The aim of this study was to investigate whether serum metal ion levels are raised in patients following total knee arthroplasty. Serum levels of chromium, cobalt, aluminium, molybdenum and zirconium were measured in two groups of patients at a minimum of 3 years after knee arthroplasty. Twenty three patients had a cobalt-chromium femoral component and 14 patients had an oxidized zirconium femoral component, acting as a control group as this femoral component is free from cobalt and chromium. All patients had the same titanium tibial base plates, and no patellae were resurfaced. Despite the lack of cobalt and chromium in the prostheses used in the control group, no statistically significant differences in serum cobalt and chromium ion levels were found between the groups. On the basis of these results there does not appear to be any significant rise in serum metal ion levels following total knee arthroplasty several years after implantation. PMID:20973359

Garrett, Simon; Jacobs, Neal; Yates, Piers; Smith, Anne; Wood, David



Total polyphenols, antioxidant and antiproliferative activities of different extracts in mungbean seeds and sprouts.  


The aim of this investigation was to evaluate the biological, alcohol dehydrogenase (ADH) and antiproliferative activities of different extracts of mungbean seeds and sprouts. All extracts from the sprouts showed higher contents of total phenolics (TP), total flavonoids (TF), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than from seeds. The highest DPPH and tyrosinase inhibition activities were registered in ethyl acetate (EtOAc) extract. ADH activity of methanol (MeOH), n-hexane (n-hexane) and n-butanol (n-BuOH) extracts from sprouts was significantly higher (P?

Kim, Dong-Kwan; Jeong, Seok Cheol; Gorinstein, Shela; Chon, Sang-Uk



How to Calculate Colourful Cross Sections Efficiently  

SciTech Connect

Different methods for the calculation of cross sections with many QCD particles are compared. To this end, CSW vertex rules, Berends-Giele recursion and Feynman-diagram based techniques are implemented as well as various methods for the treatment of colours and phase space integration. We find that typically there is only a small window of jet multiplicities, where the CSW technique has efficiencies comparable or better than both of the other two methods.

Gleisberg, Tanju; Hoeche, Stefan; Krauss, Frank




PubMed Central

The aim of this study was to evaluate the performance, as well as neuromuscular activity, in a strength task in subjects with different training backgrounds. Participants (n = 26) were divided into three groups according to their training backgrounds (aerobic, strength or mixed) and submitted to three sessions: (1) determination of the maximum oxygen uptake during the incremental treadmill test to exhaustion and familiarization of the evaluation of maximum strength (1RM) for the half squat; (2) 1RM determination; and (3) strength exercise, four sets at 80% of the 1RM, in which the maximum number of repetitions (MNR), the total weight lifted (TWL), the root mean square (RMS) and median frequency (MF) of the electromyographic (EMG) activity for the second and last repetition were computed. There was an effect of group for MNR, with the aerobic group performing a higher MNR compared to the strength group (P = 0.045), and an effect on MF with a higher value in the second repetition than in the last repetition (P = 0.016). These results demonstrated that individuals with better aerobic fitness were more fatigue resistant than strength trained individuals. The absence of differences in EMG signals indicates that individuals with different training backgrounds have a similar pattern of motor unit recruitment during a resistance exercise performed until failure, and that the greater capacity to perform the MNR probably can be explained by peripheral adaptations.

Azevedo, Neto R.M.; Julio, U.F.; Andreato, L.V.; Pinto e Silva, C.M.; Hardt, F.; Franchini, E.



Colour appearance change of a large size display under various illumination conditions  

NASA Astrophysics Data System (ADS)

This paper describes an investigation into the effect of a wide range of surround conditions on the colour appearance of test colours on a 42" plasma display panel. Experiments were conducted using surrounds including dark, indoor and outdoor conditions. Additionally the stimulus size was changed by controlling the viewing distance. The viewing conditions studied were two bright, two average, two dim and two dark surrounds. Each of the test colours was assessed by 10 observers using a magnitude estimation method. These surrounds were divided into two categories. In the first category, the surround had no effect on the displayed colours, but observers could still sense the different brightness levels of the surround. In the second category, surround introduced flare to the displayed colours together. For the first category, little visual lightness difference was shown between bright and dark, and dim and dark surround, unlike the expectation that the perceived lightness contrast may increase as the surround becomes brighter. The lightness dependency of colourfulness, however, was found to change. For the second category, the visual colour appearance of the surround conditions was plotted against measured data, CIELAB L*, C* values, to try to understand the surround effect. As the surround became brighter, the perceived dynamic range of visual lightness decreased, and the perceived colourfulness increased, more obviously in high chroma colours. In the investigation of the change of stimulus size under different surround conditions, visual colour appearance was not affected by the stimulus sizes of 2 ° and 0.6 ° in the dark surround. However, the difference was found in the very dark colours with a dim surround. Finally, all of visual colour appearance data were used to test the performance of the colour appearance model CIECAM02. Minor modification was accomplished to improve the colourfulness predictor, especially for the black background.

Choi, Seo Young; Luo, Ming Ronnier; Pointer, Michael R.



What Colour Is a Shadow?  

ERIC Educational Resources Information Center

What colour is a shadow? Black, grey, or some other colour? This article describes how to use a digital camera to test the hypothesis that a shadow under a clear blue sky has a blue tint. A white sheet of A4 paper was photographed in full sunlight and in shadow under a clear blue sky. The images were analysed using a shareware program called…

Hughes, S. W.




Microsoft Academic Search

Light sources with limited spectral content cannot render colours correctly. Typical spectra of phosphor white and RGB LEDs often result in a low colour rendering index, in spite of a high appreciation of LED lighting in visual experiments. The standard approach to colour rendering evaluation has always been based on a relative assessment: the colour coordinates of a set of

Kevin Smet; W. R. Ryckaert; G. Deconinck; Peter Hanselaer; Gebroeders Desmetstraat


Colour as visual rhetoric in financial reporting  

Microsoft Academic Search

Visual rhetoric within communication seeks to persuade through the use of picturing and encompasses words and colour. Visual rhetoric is present within annual reports. The specific role of colour in financial reporting is a neglected field of enquiry. A survey of 100 Hong Kong annual reports related colour usage to profitability change and found companies used more colour when profitability

John K. Courtis



Sexual colouration and sperm traits in guppies  

Microsoft Academic Search

The relationships among the area, hue, saturation and brightness of orange colouration and sperm traits in the guppy Poecilia reticulata were investigated. Males with greater areas of orange colouration had significantly larger sperm loads, more motile sperm and longer sperm relative to males with relatively little orange colouration. Males with greater areas of orange colouration did not possess more viable

T. E. Pitcher; F. H. Rodd; L. Rowe



Colour preferences of flower-naive honeybees  

Microsoft Academic Search

Flower-naive honeybees Apis mellifera L. flying in an enclosure were tested for their colour preferences. Bees were rewarded once on an achromatic (grey, aluminium or hardboard), or on a chromatic (ultraviolet) disk. Since naive bees never alighted on colour stimuli alone, a scent was given in combination with colour. Their landings on twelve colour stimuli were recorded. Results after one

M. Giurfa; J. Núñez; L. Chittka; R. Menzel



Effects of habitual diet on ethnic differences in serum total ghrelin  

PubMed Central

Purpose Ghrelin, an orexigenic hormone, may be involved in the etiology of obesity. African Americans (AA) experience higher obesity rates than European Americans (EA), but it is unclear whether ghrelin differs with ethnicity. This study was designed to compare ghrelin concentrations between overweight African American (AA) and European American (EA) adults in a postabsorptive state, in response to a standard meal, and after 8-week habituation to diets of differing macronutrient profiles. Methods Sixty-one overweight men and women (31 EA and 30 AA) were assigned to either a higher-carbohydrate/lower-fat diet (55% CHO, 18% PRO, 27% FAT) or a lower-carbohydrate/higher-fat diet (43% CHO, 18% PRO, 39% FAT) for 8 weeks. At baseline and week 8, participants ingested a standard liquid mixed meal. Blood was sampled before the meal and serially after ingestion to measure total ghrelin and insulin. Hunger was assessed with a visual analog scale. Composite scores for ghrelin, insulin, and hunger were calculated as area under the curve (AUC), and ghrelin suppression was calculated as the change from fasting concentration. Results Fasting ghrelin and ghrelin AUC were higher among EA at baseline and week 8 (p<0.001), and these differences were not affected by diet habituation. Despite greater postprandial ghrelin suppression, EA displayed greater hunger immediately following the test meal (p<0.05). Conclusions Overweight EA displayed higher circulating ghrelin and greater ghrelin suppression compared to AA. Further study is warranted to explore the physiological basis for these ethnic differences and to determine whether they may relate to higher obesity rates among AA.

Ellis, Amy C.; Chandler-Laney, Paula; Casazza, Krista; Goree, Laura Lee; Gower, Barbara A.




Microsoft Academic Search

Honeybees, Apis mellifera, were trained to detect coloured disks with either a strong or a weak intensity difference against the background. Green, blue, ultraviolet-reflecting white and grey papers were reciprocally combined as targets or backgrounds, providing strong chromatic and\\/or achromatic cues. The behavioural performance of the honeybees was always symmetrical for both reciprocal target\\/background combinations of a colour pair, thus



Seasonal differences in total antioxidant capacity intake from foods consumed by a Japanese population.  


Background/Objectives:This cross-sectional study aimed to estimate total antioxidant capacity (TAC) intake from food and beverages in a Japanese population from 7-day seasonal dietary records.Subjects/methods:The 7-day weighed dietary records of 390 subjects over four seasons between 1996 and 1998 were used. The TAC values (?mol trolox equivalents (?mol TE)/g) of various foods and beverages were defined, as reported in previous studies for weighed dietary records, using several different methods. TAC values of foods were estimated in 242 food and beverage items: 86.5% of vegetables, 99.1% of fruits, 71.5% of potatoes, 96.7% of beans, and 100% of chocolates. Differences in TAC intake per day and intake (g) per day among seasons in each of the food and beverage group were compared using a general linear model for repeated measures. The TAC intake/day were calculated for each food and beverage item in the four seasons.Results:TAC intake/day (?mol TE/day) varied from 10?189 (summer) to 12?292 (winter). TAC intake/day from fruits (2696) and potatoes (395) was highest in autumn, from vegetables (2827) it was highest in summer and from beans (4151) and tea (2331) it was highest in winter.Conclusions:The dietary habits of the studied Japanese population showed the highest antioxidant capacity in winter and the lowest in summer. PMID:24736680

Tatsumi, Y; Ishihara, J; Morimoto, A; Ohno, Y; Watanabe, S



Thermodynamics of two-colour QCD  

NASA Astrophysics Data System (ADS)

We discuss the thermodynamics of two-colour QCD with four flavours of staggered quarks on 8 3 × 4 and 16 3 × 4 lattices. In our simulations we use the Naik action for the fermions and a (1,2) tree-level improved gauge action. We analyze the deconfinement and chiral phase transitions for four different quark masses (m=0.1,0.05,0.025,0.015). Contrary to three-colour QCD the peak in the Polyakov loop susceptibility decreases with decreasing quark mass. This reflects an early breaking of the string in the heavy quark potential, which we verify explicitly by calculating the heavy quark potential at finite temperature using Polyakov loop correlations.

Kaczmarek, O.; Karsch, F.; Laermann, E.



Gastrointestinal tract size, total-tract digestibility, and rumen microflora in different dairy cow genotypes.  


The superior milk production efficiency of Jersey (JE) and Jersey × Holstein-Friesian (JE × HF) cows compared with Holstein-Friesian (HF) has been widely published. The biological differences among dairy cow genotypes, which could contribute to the milk production efficiency differences, have not been as widely studied however. A series of component studies were conducted using cows sourced from a longer-term genotype comparison study (JE, JE × HF, and HF). The objectives were to (1) determine if differences exist among genotypes regarding gastrointestinal tract (GIT) weight, (2) assess and quantify whether the genotypes tested differ in their ability to digest perennial ryegrass, and (3) examine the relative abundance of specific rumen microbial populations potentially relating to feed digestibility. Over 3 yr, the GIT weight was obtained from 33 HF, 35 JE, and 27 JE × HF nonlactating cows postslaughter. During the dry period the cows were offered a perennial ryegrass silage diet at maintenance level. The unadjusted GIT weight was heavier for the HF than for JE and JE × HF. When expressed as a proportion of body weight (BW), JE and JE × HF had a heavier GIT weight than HF. In vivo digestibility was evaluated on 16 each of JE, JE × HF, and HF lactating dairy cows. Cows were individually stalled, allowing for the total collection of feces and were offered freshly cut grass twice daily. During this time, daily milk yield, BW, and dry matter intake (DMI) were greater for HF and JE × HF than for JE; milk fat and protein concentration ranked oppositely. Daily milk solids yield did not differ among the 3 genotypes. Intake capacity, expressed as DMI per BW, tended to be different among treatments, with JE having the greatest DMI per BW, HF the lowest, and JE × HF being intermediate. Production efficiency, expressed as milk solids per DMI, was higher for JE than HF and JE × HF. Digestive efficiency, expressed as digestibility of dry matter, organic matter, N, neutral detergent fiber, and acid detergent fiber, was higher for JE than HF. In grazing cows (n=15 per genotype) samples of rumen fluid, collected using a transesophageal sampling device, were analyzed to determine the relative abundance of rumen microbial populations of cellulolytic bacteria, protozoa, and fungi. These are critically important for fermentation of feed into short-chain fatty acids. A decrease was observed in the relative abundance of Ruminococcus flavefaciens in the JE rumen compared with HF and JE × HF. We can deduce from this study that the JE genotype has greater digestibility and a different rumen microbial population than HF. Jersey and JE × HF cows had a proportionally greater GIT weight than HF. These differences are likely to contribute to the production efficiency differences among genotypes previously reported. PMID:24704226

Beecher, M; Buckley, F; Waters, S M; Boland, T M; Enriquez-Hidalgo, D; Deighton, M H; O'Donovan, M; Lewis, E



The Influence of Colour on Memory Performance: A Review  

PubMed Central

Human cognition involves many mental processes that are highly interrelated, such as perception, attention, memory, and thinking. An important and core cognitive process is memory, which is commonly associated with the storing and remembering of environmental information. An interesting issue in memory research is on ways to enhance memory performance, and thus, remembering of information. Can colour result in improved memory abilities? The present paper highlights the relationship between colours, attention, and memory performance. The significance of colour in different settings is presented first, followed by a description on the nature of human memory. The role of attention and emotional arousal on memory performance is discussed next. The review of several studies on colours and memory are meant to explain some empirical works done in the area and related issues that arise from such studies.

Dzulkifli, Mariam Adawiah; Mustafar, Muhammad Faiz



The acetabular component in total hip arthroplasty. Evaluation of different fixation principles.  


Initial stability is necessary for permanent fixation of acetabular cups. Biologic reactions to submicron particles such as localized bone resorption may lead to implant failure. The aim of the study was to evaluate different fixation principles of acetabular components. Four randomized studies and one case-control study were performed to evaluate different bone cements, different cup designs, use of ceramic coating or not, different type of screws and the need of additional screw fixation or not. Radiostereometry (RSA) makes it possible to analyze small translations and rotations of implants with a high accuracy. This method is suitable for evaluation of early stability and was used in four of the studies. Clinical and radiological follow-up were performed regularly. The cements were tested in the laboratory. 30 patients (mean age 71 years, range: 63-76) received total hip arthroplasties and were randomised to fixation with Boneloc (14) or Palacos cum gentamicin (16) bone cement. The curing temperature was 23 degrees lower for the Boneloc cement but the tensile strength was reduced and the elastic modulus was lower compared to Palacos. The proximal cup migration was greater in the Boneloc group up to 12 months (p 0.04) and these cups migrated medially in contrast to a small lateral migration seen in the Palacos group (p 0.04). Radiolucencies were more pronounced in the Boneloc group at 12 months (p 0.04). 155 patients (171 hips, mean age 50 years, range: 24-64) received uncemented hip arthroplasties. 84 hips were randomised to the PCA and 87 to the Harris-Galante I designs. The 10-year survival rates were 85% for the PCA and 99% for the Harris-Galante I cups (revision as end-point). The wear and clinical results did not differ. 43 patients (mean age 60 years, range 44-68) received uncemented porous cups with a titanium mesh in pure titanium (Harris-Galante II) and were randomised to additional fixation with either biodegradable screws (23, poly-L-lactic acid, PLLA) or screws made of titanium alloy (20). Increased proximal and medial-lateral translations (p 0.02, 0.04) but less rotation around the longitudinal axis (p 0.04) were seen in the PLLA group up to 2 years. There were also more pronounced radiolucencies anteriorly in this group at 2 years. The clinical results did not differ. 23 uncemented porous cups (Harris-Galante II) with hydroxyapatite-tricalciumphosphate coating (HA/TCP) were pair-wise matched to uncoated cups. Up to 2 years, decreased rotations around the horizontal axis were recorded in the HA/TCP-coated cups. Central postoperative gaps were more frequently seen in the HA/TCP group (p < 0.01), but at 2 years radiolucencies were more pronounced in the uncoated group (p < 0.01). The wear and clinical results did not differ. 62 patients (64 hips, mean age 56 years, range: 32-75) were randomized to porous Trilogy cups with (30) and without (34) cluster holes for additional screw fixation. Up to 2 years there were no differences in migration, wear, radiographic findings or clinical results. In conclusion Boneloc cement was associated with poor fixation due to inferior mechanical properties. The PLLA screws did not provide sufficient stability. Unacceptably high failure rates were recorded for the PCA cup. HA/TCP coating improved the fixation and the interface of porous cups. HA/TCP coated porous cups can be fixed without adjunctive screw fixation. PMID:10572504

Thanner, J



Exploring the benefit of synaesthetic colours: Testing for "pop-out" in individuals with grapheme-colour synaesthesia  

PubMed Central

In grapheme–colour synaesthesia, letters, numbers, and words elicit involuntary colour experiences. Recently, there has been much emphasis on individual differences and possible subcategories of synaesthetes with different underlying mechanisms. In particular, there are claims that for some, synaesthesia occurs prior to attention and awareness of the inducing stimulus. We first characterized our sample using two versions of the “Synaesthetic Congruency Task” to distinguish “projector” and “associator” synaesthetes who may differ in the extent to which their synaesthesia depends on attention and awareness. We then used a novel modification of the “Embedded Figures Task” that included a set-size manipulation to look for evidence of preattentive “pop-out” from synaesthetic colours, at both a group and an individual level. We replicate an advantage for synaesthetes over nonsynaesthetic controls on the Embedded Figures Task in accuracy, but find no support for pop-out of synaesthetic colours. We conclude that grapheme–colour synaesthetes are fundamentally similar in their visual processing to the general population, with the source of their unusual conscious colour experiences occurring late in the cognitive hierarchy.

Rich, Anina N.; Karstoft, Karen-Inge



Colour pairs for constraining the age and metallicity of stellar populations  

NASA Astrophysics Data System (ADS)

Using a widely used stellar-population synthesis model, we study the possibility of using pairs of AB system colours to break the well-known stellar age-metallicity degeneracy and to give constraints on two luminosity-weighted stellar-population parameters (age and metallicity). We present the relative age and metallicity sensitivities of the AB system colours that relate to the u,B,g,V,r,R,i, I,z,J,H and K bands, and we quantify the ability of various colour pairs to break the age-metallicity degeneracy. Our results suggest that a few pairs of colours can be used to constrain the above two stellar-population parameters. This will be very useful for exploring the stellar populations of distant galaxies. In detail, colour pairs [(r-K), (u-R)] and [(r-K), (u-r)] are shown to be the best pairs for estimating the luminosity-weighted stellar ages and metallicities of galaxies. They can constrain two stellar-population parameters on average with age uncertainties less than 3.89 Gyr and metallicity uncertainties less than 0.34 dex for typical colour uncertainties. The typical age uncertainties for young populations (age < 4.6 Gyr) and metal-rich populations (Z >= 0.001) are small (about 2.26 Gyr) while those for old populations (age >= 4.6 Gyr) and metal-poor populations (Z < 0.001) are much larger (about 6.88 Gyr). However, the metallicity uncertainties for metal-poor populations (about 0.0024) are much smaller than for other populations (about 0.015). Some other colour pairs can also possibly be used for constraining the two parameters. On the whole, the estimation of stellar-population parameters is likely to be reliable only for early-type galaxies with small colour errors and globular clusters, because such objects contain less dust. In fact, no galaxy is totally dust-free and early-type galaxies are also likely have some dust [e.g. E(B- V) ~ 0.05], which can change the stellar ages by about 2.5 Gyr and metallicities (Z) by about 0.015. When we compare the photometric estimates with previous spectroscopic estimates, we find some differences, especially when comparing the stellar ages determined by two methods. The differences mainly result from the young populations of galaxies. Therefore, it is difficult to obtain the absolute values of stellar ages and metallicities, but the results are useful for obtaining some relative values. In addition, our results suggest that colours relating to both UBVRIJHK and ugriz magnitudes are much better than either UBVRIJHK or ugriz colours for breaking the well-known degeneracy. The results also show that the stellar ages and metallicities of galaxies observed by the Sloan Digital Sky Survey and the Two-Micron All-Sky Survey can be estimated via photometry data. The data are available at the Centre de Données astronomiques de Strabourg (CDS) or on request to the authors. E-mail:

Li, Zhongmu; Han, Zhanwen



Objective evaluation of colour variation in the sand-burrowing beetle Chaerodes trachyscelides White (Coleoptera: Tenebrionidae) by instrumental determination of CIELAB values  

Microsoft Academic Search

The objective evaluation of the different colours of individual sand-burrowing beetles Chaerodes trachyscelides White illustrates that instrumental techniques may replace visual assessments and subjective descriptions of colour variation. Colour measurements based on the principles established by the Commission Intemationale d'Eclairage (CIE) provide quantitative specifications of colours as their coordinates in the 1976 CIE L*,a*,b* (CIELAB) uniform colour space. The established

A. C. Harris; I. L. Weatherall



WWW design code - a new tool for colour estimation in animal studies.  


BACKGROUND: The colour of animals' skin, fur, feathers or cuticula has been estimated in a large number of studies. The methods used to do so are diverse, with some being costly and not available to all researchers. In a study to measure plumage colour in a bird species, a new method of creating a colour chart was developed. While colour-charts have their own limitations, these can be minimised when they have the following properties: 1) being readily available to the majority of biologists, 2) containing a large array of colours to allow accurate recording and differentiation of subtle colour differences, 3) low cost, 4) adhering to a world-wide standard, and 5) being available in both hard-copy and digital formats to allow for various analytical methods. The method described below satisfies all of these requirements. RESULTS: Colour charts estimated to fit the range of the species' plumage colours were created on the computer screen using web software that allowed for HTML-coding (in this case Dreamweavertrade mark). The charts were adjusted using feathers from dead specimens until a satisfying range of darker and lighter colours were found. The resulting chart was printed out and was successfully used in the field to determine the plumage colour of hand-held birds. CONCLUSION: Access to a computer and printer, and the software to enable the creation of a chart, is within the reach of the vast majority of biologists. The numbers of colours that can be generated should suit most studies, with the advantage of the method being that the chart can be individually tailored to the species under study. HTML colour coding is a worldwide standard, thus the colours used in studies can be described in the methods section of journal articles using the six-digit alphanumeric code. We believe this method is very useful as a low-tech method for future estimation of individual colour. PMID:15679904

Berggren, Asa; Merilä, Juha



Antioxidant, total phenolic contents and antinociceptive potential of Teucrium stocksianum methanolic extract in different animal models  

PubMed Central

Background Oxidative stress and analgesia are connected with different pathological conditions. The drug candidates from synthetic sources are associated with various side effects; therefore, researchers are giving priority to find novel, effective and safe phytomedicines. Teucrium species possesses antioxidant, analgesic, anti-inflammatory and hepatoprotective activities. The essential oils of Teucrium stocksianum have shown strong antinociceptive potential. Our current study is designed to embark total phenolic content (TPC), antioxidant and antinociceptive potential of the methanolic extract of Teucrium stocksianum (METS). Method Phytochemical composition was determined by using standard methods. Free radical scavenging potential and TPC of METS were assessed by using 2, 2-diphenyl-1-picryl-hydrazyl (DPPH) and Folin-Ciocalteu Reagent (FCR) respectively. Antinociceptive potential was determined by acetic acid induced abdominal writhing, formalin induced paw licking and tail immersion tests. Different test dose 50, 100 and 150 mg/kg body weight of METS were administered intra peritonealy (i.p) to various groups of mice for the evaluation of analgesic potential. Results Phytochemical screening confirmed the presence of flavonoids, tannins, saponins, anthraquinone, steroid, phlobatannin, terpenoid, glycoside and reducing sugars. METS was found safe at a dose of 1000 mg/kg body weight. A concentration dependent free radical scavenging effect was observed with methanolic aerial parts extract of Teucrium stocksianum (MAPETS) and methanolic roots extracts of Teucrium stocksianum (MRETS). MAPETS and MRETS have shown highest antioxidant activity 91.72% and 86.19% respectively at 100 ?g/ml. MAPETS was found more rich (115.32 mg of GAE/g of dry material) in TPC as compared to MAPETS (105.41 mg of GAE/g). METS demonstrated a dose dependent antinociceptive potential in different pain models, like in acetic acid, formalin and tail immersion showing 83.103%, 80.872% and 67.58% at a dose of 150 mg/kg, similar to acetylsalicylic acid (74.79%, 82.87%, 100 mg/kg) and TramadolR (74%, 30 mg/kg) respectively. Conclusion Strong antioxidant potential and high TPCs are residing in the methanolic extract of T. stocksianum. METS showed analgesic potential in all models of nociception implying that both peripheral and central pathways of analgesia are involved. This might be due to the presence of various classes of phytochemicals in the plant extract.



Colour print workflow and methods for multilayering of colour and decorative inks using UV inkjet for fine art printing  

NASA Astrophysics Data System (ADS)

In order to increase density of colour and improve ink coverage when printing onto a range of non standard substrates, this paper will present research into multi-layering of colour and the appearance of colour at 'n' levels of ink coverage. Returning to our original investigation of artist's requirements when making inkjet prints, these observations are based on empirical approaches that address the need to present physical data that is more useful and meaningful to the designer. The study has used multi-pass printed colour charts to measure colour and to provide users with an understanding at a soft-preview level to demonstrate the appearance of printed colour on different substrates. Test results relating to the appearance of print on different surfaces, and a series of case studies will be presented using recent research into the capabilities of UV printing technology, which has widened the opportunities for the designer to print onto non-standard materials. It will also present a study into layering of greys and gloss in order to improve the appearance of printed images onto metal.

Parraman, Carinna



Bees' subtle colour preferences: how bees respond to small changes in pigment concentration.  


Variability in flower colour of animal-pollinated plants is common and caused, inter alia, by inter-individual differences in pigment concentrations. If and how pollinators, especially bees, respond to these small differences in pigment concentration is not known, but it is likely that flower colour variability impacts the choice behaviour of all flower visitors that exhibit innate and learned colour preferences. In behavioural experiments, we simulated varying pigment concentrations and studied its impact on the colour choices of bumblebees and honeybees. Individual bees were trained to artificial flowers having a specific concentration of a pigment, i.e. Acridine Orange or Aniline Blue, and then given the simultaneous choice between three test colours including the training colour, one colour of lower and one colour of higher pigment concentration. For each pigment, two set-ups were provided, covering the range of low to middle and the range of middle to high pigment concentrations. Despite the small bee-subjective perceptual contrasts between the tested stimuli and regardless of training towards medium concentrations, bees preferred neither the training stimuli nor the stimuli offering the highest pigment concentration but more often chose those stimuli offering the highest spectral purity and the highest chromatic contrast against the background. Overall, this study suggests that bees choose an intermediate pigment concentration due to its optimal conspicuousness. It is concluded that the spontaneous preferences of bees for flower colours of high spectral purity might exert selective pressure on the evolution of floral colours and of flower pigmentation. PMID:23722560

Papiorek, Sarah; Rohde, Katja; Lunau, Klaus



Ultra-realistic 3-D imaging based on colour holography  

NASA Astrophysics Data System (ADS)

A review of recent progress in colour holography is provided with new applications. Colour holography recording techniques in silver-halide emulsions are discussed. Both analogue, mainly Denisyuk colour holograms, and digitally-printed colour holograms are described and their recent improvements. An alternative to silver-halide materials are the panchromatic photopolymer materials such as the DuPont and Bayer photopolymers which are covered. The light sources used to illuminate the recorded holograms are very important to obtain ultra-realistic 3-D images. In particular the new light sources based on RGB LEDs are described. They show improved image quality over today's commonly used halogen lights. Recent work in colour holography by holographers and companies in different countries around the world are included. To record and display ultra-realistic 3-D images with perfect colour rendering are highly dependent on the correct recording technique using the optimal recording laser wavelengths, the availability of improved panchromatic recording materials and combined with new display light sources.

Bjelkhagen, H. I.



Co-Housing Rodents with Different Coat Colours as a Simple, Non-Invasive Means of Individual Identification: Validating Mixed-Strain Housing for C57BL/6 and DBA/2 Mice  

PubMed Central

Standard practice typically requires the marking of laboratory mice so that they can be individually identified. However, many of the common methods compromise the welfare of the individuals being marked (as well as requiring time, effort, and/or resources on the part of researchers and technicians). Mixing strains of different colour within a cage would allow them to be readily visually identifiable, negating the need for more invasive marking techniques. Here we assess the impact that mixed strain housing has on the phenotypes of female C57BL/6 (black) and DBA/2 (brown) mice, and on the variability in the data obtained from them. Mice were housed in either mixed strain or single strain pairs for 19 weeks, and their phenotypes then assessed using 23 different behavioural, morphological, haematological and physiological measures widely used in research and/or important for assessing mouse welfare. No negative effects of mixed strain housing could be found on the phenotypes of either strain, including variables relevant to welfare. Differences and similarities between the two strains were almost all as expected from previously published studies, and none were affected by whether mice were housed in mixed- or single-strain pairs. Only one significant main effect of housing type was detected: mixed strain pairs had smaller red blood cell distribution widths, a measure suggesting better health (findings that now need replicating in case they were Type 1 errors resulting from our multiplicity of tests). Furthermore, mixed strain housing did not increase the variation in data obtained from the mice: the standard errors for all variables were essentially identical between the two housing conditions. Mixed strain housing also made animals very easy to distinguish while in the home cage. Female DBA/2 and C57BL/6 mice can thus be housed in mixed strain pairs for identification purposes, with no apparent negative effects on their welfare or the data they generate. This suggests that there is much value in exploring other combinations of strains.

Walker, Michael; Fureix, Carole; Palme, Rupert; Mason, Georgia



A comprehensive study on the colour of virgin olive oils and its relationship with their chlorophylls and carotenoids indexes (II): CIELUV and CIELAB uniform colour spaces  

Microsoft Academic Search

The colour of up to 1700 virgin olive oil samples obtained from diverse Spanish varieties and from drupes at different maturity stages was analyzed by considering the CIELAB and CIELUV uniform colour spaces. When all the samples were considered altogether it was noticed that the range huv was considerably wider numerically than that of hab, and so was the range

M. J. Moyano; Antonio J. Meléndez-Martínez; J. Alba; Francisco J. Heredia



Colour variability of asteroids in the Sloan Digital Sky Survey Moving Object Catalog  

NASA Astrophysics Data System (ADS)

We report a detection of statistically significant colour variations for a sample of 7531 multiply observed asteroids that are listed in the Sloan Digital Sky Survey Moving Object Catalog. Using five-band photometric observations accurate to ~0.02 mag, we detect colour variations in the range 0.06-0.11 mag (rms). These variations appear to be uncorrelated with the physical characteristics of the asteroids, such as diameter (in the probed 1-10 km range), taxonomic class and family membership. Despite this lack of correlation, which implies a random nature for the cause of colour variability, a suite of tests suggest that the detected variations are not instrumental effects. In particular, the observed colour variations are incompatible with photometric errors, and, for objects observed at least four times, the colour change in the first pair of observations is correlated with the colour change in the second pair. These facts strongly suggest that the observed effect is real, and also indicate that colour variations are larger for some asteroids than for others. The detected colour variations can be explained as being due to inhomogeneous albedo distribution over an asteroid's surface. Although relatively small, these variations suggest that fairly large patches with different colour than their surroundings exist on a significant fraction of asteroids. This conclusion is in agreement with spatially resolved colour images of several large asteroids obtained by the Near Earth Asteroid Rendezvous (NEAR) spacecraft and the Hubble Space Telescope (HST).

Szabó, Gy. M.; Ivezi?, Ž.; Juri?, M.; Lupton, R.; Kiss, L. L.



Beyond the colour of my skin: How skin colour affects the sense of body-ownership  

PubMed Central

Multisensory stimulation has been shown to alter the sense of body-ownership. Given that perceived similarity between one’s own body and those of others is crucial for social cognition, we investigated whether multisensory stimulation can lead participants to experience ownership over a hand of different skin colour. Results from two studies using introspective, behavioural and physiological methods show that, following synchronous visuotactile (VT) stimulation, participants can experience body-ownership over hands that seem to belong to a different racial group. Interestingly, a baseline measure of implicit racial bias did not predict whether participants would experience the RHI, but the overall strength of experienced body-ownership seemed to predict the participants’ post-illusion implicit racial bias with those who experienced a stronger RHI showing a lower bias. These findings suggest that multisensory experiences can override strict ingroup/outgroup distinctions based on skin colour and point to a key role for sensory processing in social cognition.

Farmer, Harry; Tajadura-Jimenez, Ana; Tsakiris, Manos



Colour Glass Condensate: An Introduction.  

National Technical Information Service (NTIS)

In these lectures, the authors develop the theory of the Colour Glass Condensate. This is the matter made of gluons in the high density environment characteristic of deep inelastic scattering or hadron-hadron collisions at very high energy. The lectures a...

E. Iancu A. Leonidov L. McLerran



True three-colour photoceramic  

Microsoft Academic Search

This paper presents the true three-colour photoceramic, introduced by the authors since 1992, which allows wide new possibilities in the field of the ceramic decoration, for reproduction on ceramic (majolica, porcelain, earthenware, etc.) surfaces of images either photographic or painted images or even directly coming from computer-made image files. The correspondent technological process used to produce this kind of decoration

A. Krajewski; L. Paci



Colour of Red Blood Corpuscles  

Microsoft Academic Search

IN a recent communication1, Dr. J. R. Baker has asked why a single red blood corpuscle looks yellow instead of pink. Whether a thinned-out red colour is pink or yellow depends on the extent of its absorption in the blue end of the spectrum. Let us for simplicity regard white light as composed of equal parts of red, green and

E. J. Bowen



Interference colours of soap bubbles  

Microsoft Academic Search

In this article, we present a new versatile method for calculating the interference colour of any configuration of thin, optically isotropic, dielectric films. This method is free from common weakness of previous methods, namely the poor accuracy for large angles of incidence of light. This method gives full control over the accuracy and speed of computations, and allows for adjustments

Dariusz Jaszkowski; Janusz Rzeszut



The application of FJI and its comparison with different alimentary reconstructions after total gastrectomy for cancer  

Microsoft Academic Search

Objective  To investigate the optimum reconstruction after total gastrectomy for malignant disease, especially the necessity of gastric\\u000a substitute and duodenal passage.\\u000a \\u000a \\u000a \\u000a Methods  Among the 459 total gastrectomy cases, 6 kinds of reconstructions had been used, including Braun, modified Braun I (mBraun\\u000a I), modified Braun II (mBraun II), Roux-en-Y, “P” jejunal interposition (PJI) and functional jejunal interposition (FJI).\\u000a Postoperative complains, body weight, food

Xishan Hao; Qiang Li; Jian Yin



Comparison of different analytical methods for assessing total antioxidant capacity of human serum  

Microsoft Academic Search

Three assays were compared for the determination of total antioxidant capacity in human serum: the oxygen radical absorbance capacity (ORAC) assay, the Randox Trolox-equivalent antioxidant capacity (Randox-TEAC) assay, and the ferric reducing ability (FRAP) assay. There was a weak but significant linear correlation between serum ORAC and serum FRAP. There was no correlation either between serum ORAC and serum TEAC

Guohua Cao; Ronald L. Prior



Differences in magnetic storm and quiet ionospheric deterministic chaotic behavior: GPS total electron content analyses  

Microsoft Academic Search

In the present study we have investigated whether deterministic chaotic behavior is exhibited by the GPS total electron content (TEC) fluctuations at midlatitude ionosphere, under various geophysical conditions, using nonlinear aspects. Local slopes of the logarithms of correlation sum for the time series of TEC representing the winter storm and quiet periods exhibit a clear plateau, indicating a fractal dimension

K. Unnikrishnan; A. Saito; S. Fukao



Gender Differences in Health-Related Quality of Life Following Total Laryngectomy  

ERIC Educational Resources Information Center

Background: The impact of a total laryngectomy on an individual's life has primarily been measured from a male viewpoint reflecting the demographics of a diagnosis of laryngeal cancer. A small number of studies have looked specifically at females, but very few are comparison studies. Consequently, there is little consistent research regarding any…

Lee, Mary T.; Gibson, Sam; Hilari, Katerina



Revision of late periprosthetic infections of total hip endoprostheses: pros and cons of different concepts  

Microsoft Academic Search

Many concepts have been devised for the treatment of late periprosthetic infections of total hip prostheses. A two-stage revision with a temporary antibiotic-impregnated cement spacer and a cemented prosthesis appears to be the most preferred procedure although, in recent times, there seems to be a trend towards cementless implants and a shorter period of anti- biotic treatment. Because of the

Bernd Fink


Identifying core foods for total diet studies: a comparison of four different approaches.  


Total diet studies (TDS) are recognised as a cost-effective approach in estimating dietary exposure to chemicals in food. It has been advised that candidate foods for inclusion in TDS analysis should represent a large part of the typical diet to estimate accurately the exposure of a population group. To date a variety of approaches have been used to determine which foods should be included in a core TDS food list, with no agreed method. Therefore, the aim of this study was to compare four of these approaches by creating TDS food lists for adult populations in Europe using summary statistics data from the EFSA Comprehensive Food Consumption Database. Both a food group approach and a total diet approach were employed, and foods were selected for inclusion in the TDS food lists if they met the criteria as defined by consumption weight and/or a 5% consumer rate. Using all four approaches the representation of the diet across the TDS food lists was > 85%. The food group approach showed a slight advantage in diet representation, but produced considerably longer TDS food lists in comparison with the total diet approach. The addition of a 5% consumer rate to both approaches had little impact on results. In conclusion, the total diet approach may act as a more cost-effective approach in comparison with the food group approach while still achieving comprehensive results in the creation of core TDS food lists. PMID:24893274

Devlin, Niamh F C; McNulty, Breige A; Turrini, Aida; Tlustos, Christina; Hearty, Aine P; Volatier, Jean-Luc; Kelleher, Cecily C; Nugent, Anne P




Microsoft Academic Search

This paper is designed to provide a knowledge of the elements of colour theory and an up-to-date survey of methods of specifying colour tolerances. It is intended to fill the gap between textbooks on colour and publications that deal mainly with applications of colour theory to specific problems.

D. Leverington



The connotations of English colour terms: Colour-based X-phemisms  

Microsoft Academic Search

This paper investigates the connotations of English colour terms with particular attention to figurative uses of black, white, grey, brown, yellow, red, green, blue and a few miscellaneous colours. The connotations are judged on the basis of whether the phrases in which the colour terms occur are typically orthophemistic, euphemistic, or dysphemistic. All the colours surveyed have some, often many,

Keith Allan



Trichromacy, Opponent Colours Coding and Optimum Colour Information Transmission in the Retina  

Microsoft Academic Search

This paper presents a systematic analysis of the role of opponent type processing in colour vision and the relation between opponent type colour transformations and the initial three colour mechanisms. It is shown that efficient information transmission is achieved by a transformation of the initial three colour mechanisms into an achromatic and two opponent chromatic channels. The derivation of the

G. Buchsbaum; A. Gottschalk



Biological Components of Colour Preference in Infancy  

ERIC Educational Resources Information Center

Adult colour preference has been summarized quantitatively in terms of weights on the two fundamental neural processes that underlie early colour encoding: the S-(L+M) ("blue-yellow") and L-M ("red-green") cone-opponent contrast channels ( Ling, Hurlbert & Robinson, 2006; Hurlbert & Ling, 2007). Here, we investigate whether colour preference in…

Franklin, Anna; Bevis, Laura; Ling, Yazhu; Hurlbert, Anya



Traffic sign recognition using colour information  

Microsoft Academic Search

In this paper, we present a novel approach for the detection and recognition of traffic signs. Colour images are acquired by a camera mounted in a car. In the first step, these images are colour segmented with a pixel classifier. Colour combinations which are characteristic for traffic signs generate hypotheses. These hypotheses are verified using a pictogram classifier.Our system has

W. Ritter; F. Stein; R. Janssen



Innate colour preferences of flower visitors  

Microsoft Academic Search

Freshly emerged flower visitors exhibit colour preferences prior to individual experience with flowers. The understanding of innate colour preferences in flower visitors requires a detailed analysis, as, on the one hand, colour is a multiple-signal stimulus, and, on the other hand, flower visits include a sequence of behavioural reactions each of which can be driven by a preferential behaviour. Behavioural

K. Lunau; E. J. Maier



Nine Tools for Generating Harmonious Colour Schemes  

Microsoft Academic Search

We survey a number of tools that have been developed for generating sets of colours according to commonly accepted rules for colour harmony. Informal manual techniques for generating harmonious sets of colo urs have been known and used for at least a century. Although superficially simple, they have not been precise techniques, as pigment-based and dye-based colouring techniques are not

Paul Lyons; Giovanni Moretti



Memory for colours: a reaction time experiment  

Microsoft Academic Search

We used simultaneous and delayed match to sample tasks to investigate memory for 5 colour tests (green, yellow, purple, pink and orange) in men and women. Stimuli were emulated Munsell colour samples displayed on a CRT monitor. Colour tests were presented with distracters that could vary either in hue or in saturation. Our results indicate that: 1) over the five

V. Bonnardel; J. Herrero


Colour space models for soil science  

Microsoft Academic Search

Soil colour is an important soil property. It is frequently used by soil scientists for the identification and classification of soil. It is also used as an indicator of field soil physical, chemical and biological properties as well as of the occurrence of soil processes. Measurements of soil colour are commonly made using the Munsell soil colour charts. A number

R. A. Viscarra Rossel; B. Minasny; P. Roudier; A. B. McBratney



Analysis of brain activity and response to colour stimuli during learning tasks: an EEG study  

NASA Astrophysics Data System (ADS)

The research project intends to demonstrate how EEG detection through BCI device can improve the analysis and the interpretation of colours-driven cognitive processes through the combined approach of cognitive science and information technology methods. To this end, firstly it was decided to design an experiment based on comparing the results of the traditional (qualitative and quantitative) cognitive analysis approach with the EEG signal analysis of the evoked potentials. In our case, the sensorial stimulus is represented by the colours, while the cognitive task consists in remembering the words appearing on the screen, with different combination of foreground (words) and background colours. In this work we analysed data collected from a sample of students involved in a learning process during which they received visual stimuli based on colour variation. The stimuli concerned both the background of the text to learn and the colour of the characters. The experiment indicated some interesting results concerning the use of primary (RGB) and complementary (CMY) colours.

Folgieri, Raffaella; Lucchiari, Claudio; Marini, Daniele



Organic compounds of different extractability in total solvent extracts from soils of contrasting water repellency  

Microsoft Academic Search

Previous studies examining organic compounds that may cause water-repellent behaviour of soils have typically focussed on analysing only the lipophilic fraction of extracted material. This study aimed to provide a more comprehensive examination by applying single- and sequential-accelerated solvent extraction (ASE), separation and analysis by GC\\/MS of the total solvent extracts of three soils taken from under eucalypt vegetation with

Irena Atanassova; Stefan H. Doerr



Specification of colour changes of metallochromic indicators in the titration of bismuth with EDTA.  


The quality of the colour changes at the end-point in the complexometric titration of bismuth(III) with EDTA, using the indicators Hemotoxylin, PAN [1-(2-Pyridylazo)-Naphthol-2], PAR [4-(2-Pyridylazo)-Resorcinol], Xylenol Orange and Thoran is studied by means of the CIE 1931 trichromatic system, using specific colour discrimination (SCD) and colour difference (DeltaE*). The indicators are arranged in order of colour change quality. Of the indicators studied, Hemotoxylin is recommended as the most suitable for this titration. PMID:18965223

Prasad, K M; Raheem, S



Colour annealing - a toy model of colour reconnections  

SciTech Connect

We present a simple toy model for colour reconnections at the nonperturbative level. The model resembles an annealing-type algorithm and is applicable to any collider and process type, though we argue for a possible enhancement of the effect in hadron-hadron collisions. We present a simple application and study of the consequences for semileptonic t{bar t} events at the Tevatron.

Sandhoff, Marisa; /Wuppertal U.; Skands, Peter; /Fermilab



Colour, pleasantness, and consumption behaviour within a meal.  


It is often claimed that colour (e.g., in a meal) affects consumption behaviour. However, just how strong is the evidence in support of this claim, and what are the underlying mechanisms? It has been shown that not only the colour itself, but also the variety and the arrangement of the differently-coloured components in a meal influence consumers' ratings of the pleasantness of a meal (across time) and, to a certain extent, might even affect their consumption behaviour as well. Typically, eating the same food constantly or repeatedly leads to a decrease in its perceived pleasantness, which, as a consequence, might lead to decreased intake of that food. However, variation within a meal (in one or several sensory attributes, or holistically) has been shown to slow down this process. In this review, we first briefly summarize the literature on how general variety in a meal influences these variables and the major theories that have been put forward by researchers to explain them. We then go on to evaluate the evidence of these effects based mainly on the colour of the food explaining the different processes that might affect colour-based sensory-specific satiety and, in more detail, consumption behaviour. In addition, we also discuss the overlap in the definitions of these terms and provide additional hypothesis as to why, in some cases, the opposite pattern of results has been observed. PMID:24462488

Piqueras-Fiszman, Betina; Spence, Charles



Ethnic differences in total and HDL cholesterol among Turkish, Moroccan and Dutch ethnic groups living in Amsterdam, the Netherlands  

PubMed Central

Background High total cholesterol and low HDL (high-density lipoprotein) cholesterol are important determinants of cardiovascular disease. Little is known about dyslipidemia among Turkish and Moroccan migrants, two of the largest ethnic minority groups in several European countries. This study examines ethnic differences in total and HDL cholesterol levels between Dutch, Turkish and Moroccan ethnic groups. Methods Data were collected in the setting of a general health survey, in Amsterdam, the Netherlands, in 2004. Total response rate was 45% (Dutch: 46%, Turks: 50%, Moroccans: 39%). From 1,220 adults information on history of hypercholesterolemia, lifestyle and demographic background was obtained via health interviews. In a physical examination measurements of anthropometry and blood pressure were performed and blood was collected. Total and HDL cholesterol were determined in serum. Results Total cholesterol levels were lower and hypercholesterolemia was less prevalent among the Moroccan and Turkish than the Dutch ethnic population. HDL cholesterol was also relatively low among these migrant groups. The resulting total/HDL cholesterol ratio was particularly unfavourable among the Turkish ethnic group. Controlling for Body Mass Index and alcohol abstinence substantially attenuated ethnic differences in HDL cholesterol levels and total/HDL cholesterol ratio. Conclusions Total cholesterol levels are relatively low in Turkish and Moroccan migrants. However part of this advantage is off-set by their relatively low levels of HDL cholesterol, resulting in an unfavourable total/HDL cholesterol ratio, particularly in the Turkish population. Important factors in explaining ethnic differences are the relatively high Body Mass Index and level of alcohol abstinence in these migrant groups.




PubMed Central

A Lantern for lesting Colour-Vision is arranged to show test colours in pairs as in the Board of Trade Lantern. It is adapted to use electric light, and is standardized by stringent testing. The paper discusses the experiments and considerations which led to the formulation of the allowable tolerances in the transmission and colour co-ordinate specifications of the filters, the colour temperature of the lamps and so on. The results of tests on normal and colour-defective subjects are described.

Martin, L. C.



Risk of Complication and Revision Total Hip Arthroplasty Among Medicare Patients with Different Bearing Surfaces  

Microsoft Academic Search

Background  To address the long-term problems of bearing surface wear and osteolysis associated with conventional metal-polyethylene (M-PE)\\u000a total hip arthroplasty (THA), metal-metal (M-M), and ceramic-ceramic (C-C) bearings have been introduced. These bearing surfaces\\u000a are associated with unique risks and benefits and higher costs. However the relative risks of these three bearings in an older\\u000a population is unknown.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  We compared the short-term

Kevin J. Bozic; Kevin Ong; Edmund Lau; Steven M. Kurtz; Thomas P. Vail; Harry E. Rubash; Daniel J. Berry



Total column density variations of ozone (O 3 ) in presence of different types of clouds  

Microsoft Academic Search

The zenith sky scattered light spectra were carried out using zenith sky UV-visible spectrometer in clear and cloudy sky conditions\\u000a during May-November 2000 over the tropical station Pune (18°32?N, 73°51?E). These scattered spectra are obtained in the spectral\\u000a range 462–498 nm between 75° and 92° solar zenith angles (SZAs). The slant column densities (SCDs) as well as total column\\u000a densities

G. S. Meena



Printing colour at the optical diffraction limit.  


The highest possible resolution for printed colour images is determined by the diffraction limit of visible light. To achieve this limit, individual colour elements (or pixels) with a pitch of 250 nm are required, translating into printed images at a resolution of ?100,000 dots per inch (d.p.i.). However, methods for dispensing multiple colourants or fabricating structural colour through plasmonic structures have insufficient resolution and limited scalability. Here, we present a non-colourant method that achieves bright-field colour prints with resolutions up to the optical diffraction limit. Colour information is encoded in the dimensional parameters of metal nanostructures, so that tuning their plasmon resonance determines the colours of the individual pixels. Our colour-mapping strategy produces images with both sharp colour changes and fine tonal variations, is amenable to large-volume colour printing via nanoimprint lithography, and could be useful in making microimages for security, steganography, nanoscale optical filters and high-density spectrally encoded optical data storage. PMID:22886173

Kumar, Karthik; Duan, Huigao; Hegde, Ravi S; Koh, Samuel C W; Wei, Jennifer N; Yang, Joel K W



Printing colour at the optical diffraction limit  

NASA Astrophysics Data System (ADS)

The highest possible resolution for printed colour images is determined by the diffraction limit of visible light. To achieve this limit, individual colour elements (or pixels) with a pitch of 250 nm are required, translating into printed images at a resolution of ~100,000 dots per inch (d.p.i.). However, methods for dispensing multiple colourants or fabricating structural colour through plasmonic structures have insufficient resolution and limited scalability. Here, we present a non-colourant method that achieves bright-field colour prints with resolutions up to the optical diffraction limit. Colour information is encoded in the dimensional parameters of metal nanostructures, so that tuning their plasmon resonance determines the colours of the individual pixels. Our colour-mapping strategy produces images with both sharp colour changes and fine tonal variations, is amenable to large-volume colour printing via nanoimprint lithography, and could be useful in making microimages for security, steganography, nanoscale optical filters and high-density spectrally encoded optical data storage.

Kumar, Karthik; Duan, Huigao; Hegde, Ravi S.; Koh, Samuel C. W.; Wei, Jennifer N.; Yang, Joel K. W.



Accuracy of different sensors for the estimation of pollutant concentrations (total suspended solids, total and dissolved chemical oxygen demand) in wastewater and stormwater.  


Many field investigations have used continuous sensors (turbidimeters and/or ultraviolet (UV)-visible spectrophotometers) to estimate with a short time step pollutant concentrations in sewer systems. Few, if any, publications compare the performance of various sensors for the same set of samples. Different surrogate sensors (turbidity sensors, UV-visible spectrophotometer, pH meter, conductivity meter and microwave sensor) were tested to link concentrations of total suspended solids (TSS), total and dissolved chemical oxygen demand (COD), and sensors' outputs. In the combined sewer at the inlet of a wastewater treatment plant, 94 samples were collected during dry weather, 44 samples were collected during wet weather, and 165 samples were collected under both dry and wet weather conditions. From these samples, triplicate standard laboratory analyses were performed and corresponding sensors outputs were recorded. Two outlier detection methods were developed, based, respectively, on the Mahalanobis and Euclidean distances. Several hundred regression models were tested, and the best ones (according to the root mean square error criterion) are presented in order of decreasing performance. No sensor appears as the best one for all three investigated pollutants. PMID:23863442

Lepot, Mathieu; Aubin, Jean-Baptiste; Bertrand-Krajewski, Jean-Luc



Cultural transmission results in convergence towards colour term universals  

PubMed Central

As in biological evolution, multiple forces are involved in cultural evolution. One force is analogous to selection, and acts on differences in the fitness of aspects of culture by influencing who people choose to learn from. Another force is analogous to mutation, and influences how culture changes over time owing to errors in learning and the effects of cognitive biases. Which of these forces need to be appealed to in explaining any particular aspect of human cultures is an open question. We present a study that explores this question empirically, examining the role that the cognitive biases that influence cultural transmission might play in universals of colour naming. In a large-scale laboratory experiment, participants were shown labelled examples from novel artificial systems of colour terms and were asked to classify other colours on the basis of those examples. The responses of each participant were used to generate the examples seen by subsequent participants. By simulating cultural transmission in the laboratory, we were able to isolate a single evolutionary force—the effects of cognitive biases, analogous to mutation—and examine its consequences. Our results show that this process produces convergence towards systems of colour terms similar to those seen across human languages, providing support for the conclusion that the effects of cognitive biases, brought out through cultural transmission, can account for universals in colour naming.

Xu, Jing; Dowman, Mike; Griffiths, Thomas L.



Automatic channel allocation for small wireless local area networks using graph colouring algorithm approach  

Microsoft Academic Search

Classical graph colouring and its generalisations have been used to model various frequency and channel allocation processes in different radio and wireless network contexts for some time now. However, most of this work has targeted cellular networks and graphs with a relatively large number of nodes. In this article we demonstrate how graph colouring can be used as a theoretical

Petri Mähönen; Janne Riihijärvi; Marina Petrova



Experimental manipulation reveals differential effects of colour pattern on survival in male and female pygmy grasshoppers  

Microsoft Academic Search

Populations of pygmy grasshoppers, Tetrix subulata, exhibit genetically coded discontinuous variation in colour pattern. To determine whether the dynamics of this polymorphism is likely to be affected by selective processes, rather than by stochastic events, we experimentally manipulated colour patterns of free- ranging grasshoppers and then calculated and controlled for differences in capture probabilities between categories of individuals before estimating




Colour tuning in human visual cortex measured with functional magnetic resonance imaging  

Microsoft Academic Search

The primate retina contains three classes of cones, the L, M and S cones, which respond preferentially to long-, middle- and short-wavelength visible light, respectively. Colour appearance results from neural processing of these cone signals within the retina and the brain. Perceptual experiments have identified three types of neural pathways that represent colour: a red-green pathway that signals differences between

Stephen Engel; Xuemei Zhang; Brian Wandell



Training Grapheme-Colour Associations Produces a Synaesthetic Stroop Effect, but Not a Conditioned Synaesthetic Response  

ERIC Educational Resources Information Center

The goal of this study was to investigate whether behavioural and physiological consequences of synaesthesia can be elicited by training specific letter-colour associations. Towards this goal 20 non-synaesthetic individuals were trained for 10 min on 7 consecutive days to associate four different letters with four specific colours. After training,…

Meier, Beat; Rothen, Nicolas



Evaluation of radical scavenging potential and total phenol content in Woodfordia fruticosa from different altitudes  

Microsoft Academic Search

Woodfordia fruticosa Kurz is a member of family Lythraceae, commonly used in the treatment of diseases like leucorrhoea, dysentery, leprosy and\\u000a menorrhagia. The plant material such as leaves, bark and flowers were collected from three different (200, 402 and 600 m)\\u000a altitudes of Khandala (M.S. India) and the extracts were prepared in solvents like methanol, ethanol and distilled water.\\u000a The radical

Palak Akshyesh Chaturvedi; Arindam Alok Ghatak; Neetin Shivajirao Desai


Composition of pigments and colour changes in green table olives related to processing type.  


Brownish colourations in Natural green table olives (non-treated with alkali) make this product less attractive to consumers than Spanish-style green table olives (treated with alkali), which develop a more appreciated bright golden-yellow colour. These colour differences were studied in relation to changes in the composition of chlorophyll and carotenoid pigments, as well as polyphenolic compounds and polyphenol oxidase enzyme (PPO) activity. Natural green olives showed a different chlorophyll profile than Spanish-style. However, all the chlorophyll pigments formed in both processing types were Mg-free derivatives (mostly pheophytins) with similar colourations, ranging from grey to green brownish. In the carotenoid fraction no appreciable differences were found between both processing types. The fruit's brownish colour was mainly due to polymeric substances with a size of >1000 daltons and polyphenolic nature, resulting from an enzymatic oxidation by PPO of the o-diphenolic compounds present in the fresh fruits. PMID:25053036

Ramírez, Eva; Gandul-Rojas, Beatriz; Romero, Concepción; Brenes, Manuel; Gallardo-Guerrero, Lourdes



Individual quality explains association between plumage colouration, arrival dates and mate acquisition in yellow warblers (Setophaga petechia)  

PubMed Central

Background In many bird species colour traits influence social dominance and breeding success. In our study we first evaluated whether the colour of the basic plumage (tail feathers grown at the end of the breeding season), that provides an index of individual quality, influenced winter habitat use by yellow warblers. We then evaluated whether winter habitat use (inferred using ?13C and ?15N signatures of winter grown greater-coverts) influenced alternate plumage colouration, after controlling for individual quality using basic plumage colouration. Finally, we investigated whether basic and alternate plumage colouration influenced arrival dates, mate acquisition, breeding phenology and reproductive success of yellow warblers breeding in southern (Revelstoke, B.C.) and arctic (Inuvik, N.W.T.) Canada. Results The colour (chroma and hue) of tail feathers, grown on the breeding grounds, was not related to subsequent winter habitat use. Greater covert and tail feather colour (chroma and hue) were correlated, suggesting genetics and/or individual quality played a role in pigment deposition. After controlling for individual difference in tail colour, ?13C values did not explain any variation in greater covert colour, but birds with high ?15N signatures had greater coverts with higher chroma. Male arrival dates varied with tail chroma in Revelstoke and tail hue in Inuvik. Males that arrived early paired with older and/or more colourful mates that initiated clutches earlier, and at one site (Revelstoke) were more likely to fledge young. In addition, in Revelstoke (but not Inuvik) males with high tail hue also acquired more colourful mates. In contrast, after controlling for individual differences in tail colour, greater covert colour did not affect male arrival date, the quality of the mate obtained or reproductive success in either population. Conclusions Our results suggest that plumage colour effects on breeding phenology and mate acquisition result from differences in the intrinsic quality of individuals rather than a carry-over effect of winter habitat use.



Improved Detection of Quantitative Differences Using a Combination of Spectral Counting and MS/MS Total Ion Current  

PubMed Central

Label-free quantitative strategies are commonly used in shot-gun proteomics to detect differences in protein abundance between biological sample groups. Here, we have employed a combination of two such approaches, spectral counting (SpC) and average MS/MS total ion current (MS2 TIC), for the analysis of rat kidney mitochondria in response to metabolic acidosis. In total, forty nine proteins were observed to be significantly altered in response to metabolic acidosis (p-value < 0.05). Of these, 32 proteins were uniquely observed as significantly different by SpC, 14 by MS2 TIC, and only 3 by both approaches. Western blot analysis was performed on a subset of these proteins to validate the observed abundance differences. This study illustrates the utility and ease of combining these two label-free quantitative approaches to increase the number of detected protein abundance differences in the shot-gun analysis of complex biological samples.

Freund, Dana M.



Frequency, phase, and colour coding in apparent motion: 2.  


In an earlier paper, Caelli and Finlay demonstrated that the perception of apparent motion was contingent on critical phase relationships between inducing sources, and their spatio-temporal frequency ranges. In their original stimulus red-green centre-surround sources were used and phase-specific inhibition was found at 60 degrees--90 degreee phase angle differences between the complementarily coloured elements. In this experiment we show that, when centre-surround sources are replaced by vertically-horizontally displaced complementary (or identically coloured) sources, symmetrical phase inhibition effects occur with both motions. PMID:503790

Finlay, D; Caelli, T



Variable-rate colour image quantization based on quadtree segmentation  

NASA Astrophysics Data System (ADS)

A novel variable-sized block encoding with threshold control for colour image quantization (CIQ) is presented in this paper. In CIQ, the colour palette used has a great influence on the reconstructed image quality. Typically, a higher image quality and a larger storage cost are obtained when a larger-sized palette is used in CIQ. To cut down the storage cost while preserving quality of the reconstructed images, the threshold control policy for quadtree segmentation is used in this paper. Experimental results show that the proposed method adaptively provides desired bit rates while having better image qualities comparing to CIQ with the usage of multiple palettes of different sizes.

Hu, Y. C.; Li, C. Y.; Chuang, J. C.; Lo, C. C.



The original colours of fossil beetles  

PubMed Central

Structural colours, the most intense, reflective and pure colours in nature, are generated when light is scattered by complex nanostructures. Metallic structural colours are widespread among modern insects and can be preserved in their fossil counterparts, but it is unclear whether the colours have been altered during fossilization, and whether the absence of colours is always real. To resolve these issues, we investigated fossil beetles from five Cenozoic biotas. Metallic colours in these specimens are generated by an epicuticular multi-layer reflector; the fidelity of its preservation correlates with that of other key cuticular ultrastructures. Where these other ultrastructures are well preserved in non-metallic fossil specimens, we can infer that the original cuticle lacked a multi-layer reflector; its absence in the fossil is not a preservational artefact. Reconstructions of the original colours of the fossils based on the structure of the multi-layer reflector show that the preserved colours are offset systematically to longer wavelengths; this probably reflects alteration of the refractive index of the epicuticle during fossilization. These findings will allow the former presence, and original hue, of metallic structural colours to be identified in diverse fossil insects, thus providing critical evidence of the evolution of structural colour in this group.

McNamara, Maria E.; Briggs, Derek E. G.; Orr, Patrick J.; Noh, Heeso; Cao, Hui



Changes in bone mineral density adjacent to two biomechanically different types of cementless femoral stems in total hip arthroplasty  

Microsoft Academic Search

.  \\u000a We have compared the differences in bone mineral density (BMD) adjacent to two biomechanically different cementless femoral\\u000a stems used for total hip arthroplasty. Measurements were performed 12 to 38 months after surgery in a cross sectional study\\u000a of 29 patients. Of these, 15 had arthroplasties using an ”off the shelf” type cementless femoral stem (Spotorno), while 14\\u000a had a

B. Zerahn; M. Storgaard; T. Johansen; C. Olsen; G. Lausten; I.-L. Kanstrup



Investigation of effect of different total area coverage values of inks on reflection spectra and color gamut  

NASA Astrophysics Data System (ADS)

The paper presents investigation of the effect of different values of total area coverage of inks (TAC) on reflection spectra and color gamut. Total area coverage is a key factor for achieving of maximal volume of color gamut. The reflection spectra of color surfaces in entire visible spectrum are used for determination the effect of different values of TAC. For study the effect of TAC values on color gamut, we have used special test form that contains many components and test charts with over 1500 color patches. According to measurement of reflectance spectrum of test charts, we have compared the color gamuts with different values of TAC to obtain comprehensive information of all colors, which could be reproduced in the specific conditions. In addition we have converted the reflection spectra data to CIE L*a*b* coordinates, and we have calculated the color difference ?E* ab to determine the effect of TAC on color reproduction accuracy. The main goal of this study is development of methodology, which gives objective and analytical assessment, for determining the optimal value of total area coverage (TAC). A practical implementation of the correct and optimal value of total area coverage should improve the printability, better ink layers adhesion, biggest number of trapping values and reduce the quantity of process inks. The optimal value of the TAC determined by this new methodology helps to achieve a significant reduction of ink cost and a maximal color gamut volume, i.e. improve the quality of printed image and reduce financial costs.

Spiridonov, I.; Shopova, M.; Boeva, R.



True and false memory for colour names versus actual colours: support for the visual distinctiveness heuristic in memory for colour information.  


In a colour variation of the Deese-Roediger-McDermott (DRM) false memory paradigm, participants studied lists of words critically related to a nonstudied colour name (e.g., "blood, cherry, scarlet, rouge ... "); they later showed false memory for the critical colour name (e.g., "red"). Two additional experiments suggest that participants generate colour imagery in response to such colour-related DRM lists. First, participants claim to experience colour imagery more often following colour-related than standard non-colour-related DRM lists; they also rate their colour imagery as more vivid following colour-related lists. Second, participants exhibit facilitative priming for critical colours in a dot selection task that follows words in the colour-related DRM list, suggesting that colour-related DRM lists prime participants for the actual critical colours themselves. Despite these findings, false memory for critical colour names does not extend to the actual colours themselves (font colours). Rather than leading to source confusion about which colours were self-generated and which were studied, presenting the study lists in varied font colours actually worked to reduce false memory overall. Results are interpreted within the framework of the visual distinctiveness hypothesis. PMID:19941197

Eslick, Andrea N; Kostic, Bogdan; Cleary, Anne M



Coevolution and the adaptive value of autumn tree colours: colour preference and growth rates of a southern beech aphid.  


The evolutionary explanation for the change in leaf colour during autumn is still debated. Autumn colours could be a signal of defensive commitment towards insects (coevolution) or an adaptation against physical damage because of light at low temperatures (photoprotection). These two hypotheses have different predictions: (1) under the coevolution hypothesis, insects should not prefer red leaves in autumn and grow better in spring on trees with green autumn leaves; and (2) under the photoprotection hypothesis, insects should prefer and grow better on trees with red leaves because they provide better nutrition. Studying colour preference in autumn and growth rates in spring of a southern beech aphid species (Neuquenaphis staryi) on Nothofagus alessandrii, we found preference for green leaves in autumn but no differential performance of aphids in spring. We suggest that aphid preference for green might have evolved to exploit better their host during the autumn rather than to improve their performance in spring. PMID:18034803

Ramírez, C C; Lavandero, B; Archetti, M




Microsoft Academic Search

Although durum wheat is the cereal of choice for pasta production, in many areas of Argentina pasta is made from bread wheat, since durum wheat is cultivated only in a small region of the country. The purpose of this work was determining the influence of different bread flours on the colour of laminated fresh pasta. Triticale flour was also studied.

C. S. Martinez; P. D. Ribotta; A. E. Leon; M. C. Añon



Does genome size in Dasypyrum villosum vary with fruit colour?  

Microsoft Academic Search

Dasypyrum villosum (2n=14), a Mediterranean grass species of the Triticeae, exhibits intraindividual fruit colour polymorphism from pale yellow to almost black. Several studies have reported differences between the plants emerging from pale and dark fruits. They include histone content in root meristem nuclei, cell cycle duration, heterochromatin banding pattern, frequency of a tandemly repeated sequence, and nuclear genome size. In

R Obermayer; J Greilhuber



Colour Assessment on Bread Wheat and Triticale Fresh Pasta  

Microsoft Academic Search

Although durum wheat is the cereal of choice for pasta production, in many areas of Argentina pasta is made from bread wheat, since durum wheat is cultivated only in a small region of the country. The purpose of this work was to determine the influence of different bread flours on the colour of laminated fresh pasta. Triticale flour was also

C. S. Martinez; P. D. Ribotta; A. E. Leon; M. C. Añon



RGB-NDVI colour composites for visualizing forest change dynamics  

Microsoft Academic Search

A simple and logical technique was developed to display and quantify forest change using three dates of satellite imagery. The normalized difference vegetation index (NDVI) was computed for each date of imagery to define high and low vegetation biomass. Colour composites were generated by combining each date of NDVI with either the red, green, or blue (RGB) image planes in




On the relationship between the phases of 27-day total ozone and solar activity indices in different latitudinal zones  

NASA Technical Reports Server (NTRS)

The dynamics of 27 day total ozone variations during and 11 year solar activity cycle at high and low latitudes was analyzed. The calculations were made using a specially worked out program permitting, besides the determination of the amplitudes and phases, the observation of the coherence of phases in any time interval. To characterize solar activity, solar radio-flux at 10.7 cm was used. The results of the calculation of total ozone phases difference and those of the index F(sub 10.7), as well as the amplitudes of the 27 day variations of these parameters are presented.

Ivanova, I. N.; Krivolutsky, A. A.; Kuznetsova, V. N.



Colour Consideration for Waiting areas in hospitals  

NASA Astrophysics Data System (ADS)

Colour is one the most important factors in the nature that can have some affects on human behaviour. Many years ago, it was proven that using colour in public place can have some affect on the users. Depend of the darkness and lightness; it can be vary from positive to negative. The research will mainly focus on the colour and psychological influences and physical factors. The statement of problem in this research is what is impact of colour usually applied to waiting area? The overall aim of the study is to explore the visual environment of hospitals and to manage the colour psychological effect of the hospital users in the waiting area by creating a comfortable, pleasant and cozy environment for users while spend their time in waiting areas. The analysisconcentrate on satisfaction and their interesting regarding applied colour in two private hospital waiting area in Malaysia.

Zraati, Parisa



Colour-independent partition functions in coloured vertex models  

NASA Astrophysics Data System (ADS)

We study lattice configurations related to Sn, the scalar product of an off-shell state and an on-shell state in rational An integrable vertex models, n?{1,2}. The lattice lines are colourless and oriented. The state variables are n conserved colours that flow along the line orientations, but do not necessarily cover every bond in the lattice. Choosing boundary conditions such that the positions where the colours flow into the lattice are fixed, and where they flow out are summed over, we show that the partition functions of these configurations, with these boundary conditions, are n-independent. Our results extend to trigonometric An models, and to all n. This n-independence explains, in vertex-model terms, results from recent studies of S2 (Caetano and Vieira, 2012, [1], Wheeler, arXiv:1204.2089, [2]). Namely, 1.S2, which depends on two sets of Bethe roots, {b1} and {b2}, and cannot (as far as we know) be expressed in single determinant form, degenerates in the limit {b1}??, and/or {b2}??, into a product of determinants, 2. Each of the latter determinants is an A1 vertex-model partition function.

Foda, O.; Wheeler, M.



AFLP genome scans suggest divergent selection on colour patterning in allopatric colour morphs of a cichlid fish.  


Genome scan-based tests for selection are directly applicable to natural populations to study the genetic and evolutionary mechanisms behind phenotypic differentiation. We conducted AFLP genome scans in three distinct geographic colour morphs of the cichlid fish Tropheus moorii to assess whether the extant, allopatric colour pattern differentiation can be explained by drift and to identify markers mapping to genomic regions possibly involved in colour patterning. The tested morphs occupy adjacent shore sections in southern Lake Tanganyika and are separated from each other by major habitat barriers. The genome scans revealed significant genetic structure between morphs, but a very low proportion of loci fixed for alternative AFLP alleles in different morphs. This high level of polymorphism within morphs suggested that colour pattern differentiation did not result exclusively from neutral processes. Outlier detection methods identified six loci with excess differentiation in the comparison between a bluish and a yellow-blotch morph and five different outlier loci in comparisons of each of these morphs with a red morph. As population expansions and the genetic structure of Tropheus make the outlier approach prone to false-positive signals of selection, we examined the correlation between outlier locus alleles and colour phenotypes in a genetic and phenotypic cline between two morphs. Distributions of allele frequencies at one outlier locus were indeed consistent with linkage to a colour locus. Despite the challenges posed by population structure and demography, our results encourage the cautious application of genome scans to studies of divergent selection in subdivided and recently expanded populations. PMID:22625655

Mattersdorfer, Karin; Koblmüller, Stephan; Sefc, Kristina M



Coat colour and sex identification in horses from Iron Age Sweden.  


Domestication of animals and plants marked a turning point in human prehistory. To date archaeology, archaeozoology and genetics have shed light on when and where all of our major livestock species were domesticated. Phenotypic changes associated with domestication have occurred in all farm animals. Coat colour is one of the traits that have been subjected to the strongest human selection throughout history. Here we use genotyping of coat colour SNPs in horses to investigate whether there were any regional differences or preferences for specific colours associated with specific cultural traditions in Iron Age Sweden. We do this by identifying the sex and coat colour of horses sacrificed at Skedemosse, Öland (Sweden) during the Iron Age, as well as in horses from two sites in Uppland, Ultuna and Valsgärde (dated to late Iron Age). We show that bay, black and chestnut colours were all common and two horses with tobiano spotting were found. We also show how the combination of sex identification with genotyping of just a few SNPs underlying the basic coat colours can be used to identify the minimum number of individuals at a site on a higher level than morphological methods alone. Although separated by 500 km and from significantly different archaeological contexts the horses at Skedemosse and Ultuna are quite homogenous when it comes to coat colour phenotypes, indicating that there were no clear geographical variation in coat colouration in Sweden during the late Iron Age and early Viking Age. PMID:22154005

Svensson, Emma M; Telldahl, Ylva; Sjöling, Emma; Sundkvist, Anneli; Hulth, Helena; Sjøvold, Torstein; Götherström, Anders



Colour Gradients in Clusters of Galaxies  

NASA Astrophysics Data System (ADS)

We investigate the environmental effects (interactions/mergers, ram preasure stripping) in clusters of galaxies by means of colour gradients. These effects affect the photometrical properties of clusters, enhancing the fraction of blue galaxies (Butcher-Oemler effect). In this paper we determine the colour gradients frac{d(B-V)}{dR} in 13 clusters of galaxies, with redshifts 0.198 < = z < = 0.81, and investigate their cosmological dependence. The problem of colour evolution of galaxies in clusters, the connexion between the colour gradients and the Butcher-Oemler effect are also discussed.

Suran, M. D.; Popescu, N. A.


How temporal cues can aid colour constancy  

PubMed Central

Colour constancy assessed by asymmetric simultaneous colour matching usually reveals limited levels of performance in the unadapted eye. Yet observers can readily discriminate illuminant changes on a scene from changes in the spectral reflectances of the surfaces making up the scene. This ability is probably based on judgements of relational colour constancy, in turn based on the physical stability of spatial ratios of cone excitations under illuminant changes. Evidence is presented suggesting that the ability to detect violations in relational colour constancy depends on temporal transient cues. Because colour constancy and relational colour constancy are closely connected, it should be possible to improve estimates of colour constancy by introducing similar transient cues into the matching task. To test this hypothesis, an experiment was performed in which observers made surface-colour matches between patterns presented in the same position in an alternating sequence with period 2 s or, as a control, presented simultaneously, side-by-side. The degree of constancy was significantly higher for sequential presentation, reaching 87% for matches averaged over 20 observers. Temporal cues may offer a useful source of information for making colour-constancy judgements.

Foster, David H.; Amano, Kinjiro; Nascimento, Sergio M. C.



Differences in gait characteristics between total hip, knee, and ankle arthroplasty patients: a six-month postoperative comparison  

PubMed Central

Background The recovery of gait ability is one of the primary goals for patients following total arthroplasty of lower-limb joints. The aim of this study was to objectively compare gait differences of patients after unilateral total hip arthroplasty (THA), total knee arthroplasty (TKA) and total ankle arthroplasty (TAA) with a group of healthy controls. Methods A total of 26 TAA, 26 TKA and 26 THA patients with a mean (± SD) age of 64 (± 9) years were evaluated six months after surgery and compared with 26 matched healthy controls. Subjects were asked to walk at self-selected normal and fast speeds on a validated pressure mat. The following spatiotemporal gait parameters were measured: walking velocity, cadence, single-limb support (SLS) time, double-limb support (DLS) time, stance time, step length and step width. Results TAA and TKA patients walked slower than controls at normal (p<0.05) and fast speeds (p<0.01). The involved side of TAA and TKA patients showed shorter SLS compared to controls at both normal and fast speeds (p<0.01). Regardless of walking speed, the uninvolved side of TAA and TKA patients demonstrated longer stance time and shorter step length than controls (p<0.01). TAA patients showed shorter SLS of the involved side, longer stance time and shorter step length of the uninvolved side compared to the contralateral side at both normal and fast speeds (p<0.001). Conclusions Gait disability after unilateral lower-limb joint arthroplasty was more marked for distal than for proximal joints at six months after surgery, with a proximal-to-distal progression in the impairment (TAA>TKA>THA). THA patients demonstrated no gait differences compared with controls. In contrast, TAA and TKA patients still demonstrated gait differences compared to controls, with slower walking velocity and reduced SLS in the involved limb. In addition, TAA patients presented marked side-to-side asymmetries in gait characteristics.



On the colour contribution to effective weak vertex in broken colour gauge theories  

Microsoft Academic Search

Treating the breaking of colour symmetry via the mixing between the colour gluons and weak bosons (a la Rajasekaran and Roy)\\u000a it is observed that the colour contribution to the effective weak vertex of a quark at zero momentum transfer is zero uptoO(?).

R Ramachandran



Effects of different soil management practices on total P and Olsen-P sediment loss: A field rainfall simulation study  

Microsoft Academic Search

Field rainfall simulations were conducted in 2002 and 2005 to study the effects of different soil management practices on the total phosphorous (TP) and Olsen-P losses by soil erosion and redistribution along a 15 m long slope in Luoyang, Henan province, China. Field plots were set up in 2001 and included the following soil management practices: subsoiling with mulch (SSM), no-till

K. Jin; W. M. Cornelis; W. Schiettecatte; J. J. Lu; D. X. Cai; J. Y. Jin; S. De Neve; R. Hartmann; D. Gabriels



Measuring microRNAs: Comparisons of microarray and quantitative PCR measurements, and of different total RNA prep methods  

Microsoft Academic Search

BACKGROUND: Determining the expression levels of microRNAs (miRNAs) is of great interest to researchers in many areas of biology, given the significant roles these molecules play in cellular regulation. Two common methods for measuring miRNAs in a total RNA sample are microarrays and quantitative RT-PCR (qPCR). To understand the results of studies that use these two different techniques to measure

Robert A Ach; Hui Wang; Bo Curry



Influence of Fatty Acid Profile of Total Parenteral Nutrition Emulsions on the Fatty Acid Composition of Different Tissues of Piglets  

Microsoft Academic Search

Total parenteral nutrition (TPN) studies in human babies of very-low-birth-weight suggest that the lipid emulsions currently\\u000a available are not optimum for neonatal nutrition. Since fatty acid metabolism in human and pigs is very similar, the present\\u000a study examines how lipid emulsions used in clinical TPN (i.e. ClinOleic, Intralipid, Lipofundin or Omegaven), with different\\u000a fatty acid compositions, administered to neonatal piglets

E. Amusquivar; M. Sánchez; M. J. Hyde; J. Laws; L. Clarke; E. Herrera



Male-male competition and nuptial-colour displacement as a diversifying force in Lake Victoria cichlid fishes.  

PubMed Central

We propose a new mechanism for diversification of male nuptial-colour patterns in the rapidly speciating cichlid fishes of Lake Victoria. Sympatric closely related species often display nuptial colours at opposite ends of the spectrum with males either blue or yellow to red. Colour polymorphisms within single populations are common too. We propose that competition between males for breeding sites promotes such colour diversification, and thereby speciation. We hypothesize that male aggression is primarily directed towards males of the common colour, and that rare colour morphs enjoy a negatively frequency-dependent fitness advantage. We test our hypothesis with a large dataset on the distributions and nuptial colorations of 52 species on 47 habitat islands in Lake Victoria, and with a smaller dataset on the within-spawning-site distributions of males with different coloration. We report that territories of males of the same colour are negatively associated on the spawning site, and that the distribution of closely related species over habitat islands is determined by nuptial coloration in the fashion predicted by our hypothesis. Whereas among unrelated species those with similar nuptial colour are positively associated, among closely related species those with similar colour are negatively associated and those with different colour are positively associated. This implies that negatively frequency-dependent selection on nuptial coloration among closely related species is a sufficiently strong force to override other effects on species distributions. We suggest that male-male competition is an important and previously neglected agent of diversification among haplochromine cichlid fishes.

Seehausen, Ole; Schluter, Dolph



Chick colour approach preferences are altered by cold stress; colour pecking and approach preferences are the same.  


Colour approach preferences in 1-day-old New Hampshire and White Leghorn chicks were assessed by choice preference tests between pairs of differently coloured floors, illuminated by light passed through different interference filters and adjusted to equal luminance. In experiment 1, the preferences found closely resembled colour pecking preferences reported previously for domestic chicks, e.g. a preference for blue over green. Experiment 2 showed that the latter preference could be reversed by cold stress. That is, chicks tested similarly but in a cold noisy room (18.9 C) preferred green over blue. Experiment 3 eliminated the role of noise in this reversal effect, since chicks tested in a warm noisy room showed the normal blue over green preference. It was concluded, in disagreement with prior findings and their interpretations, that chick colour pecking and approach preferences are normally the same, not different, and certainly not spectral mirror-image reversals. Instead, a more restricted preference reversal (i.e. in the blue-green spectral regions) occurs as a result of cold stress. PMID:565177

Davis, S J; Fischer, G J



The adaptive significance of ontogenetic colour change in a tropical python.  


Ontogenetic colour change is typically associated with changes in size, vulnerability or habitat, but assessment of its functional significance requires quantification of the colour signals from the receivers' perspective. The tropical python, Morelia viridis, is an ideal species to establish the functional significance of ontogenetic colour change. Neonates hatch either yellow or red and both the morphs change to green with age. Here, we show that colour change from red or yellow to green provides camouflage from visually oriented avian predators in the different habitats used by juveniles and adults. This reflects changes in foraging behaviour and vulnerability as individuals mature and provides a rare demonstration of the adaptive value of ontogenetic colour change. PMID:17443961

Wilson, David; Heinsohn, Robert; Endler, John A



Evidence for the existence of colour mechanisms producing unique hues as derived from a colour illusion based on spatio-chromatic interactions.  


When its spatial frequency is high enough, a grid of grey horizontal strips presented on a coloured background may change its neutral colour. It was found that some background colours induce a strong illusion and some no illusion at all. The effect of the background colour on the illusion was studied for the spatial frequencies of 0.5, 2.5, 4, and 8 c/deg. Thirty chromaticities (evenly distributed across the colour gamut triangle) of the backgrounds in the equiluminant plane, and 24 in the ML plane (where S-contrast was zero), were tested. Five matches were made for each frequency and each background chromaticity. Viewing was binocular. For the low (0.5 c/deg) frequency strips, the backgrounds were found to induce the colour, if any, approximately complimentary to that of the background (i.e., chromatic simultaneous contrast). For the high (8 c/deg) frequency, most backgrounds induced only illusory colours close to unique hues (yellow, blue, and green), with a few backgrounds inducing a mixture of green with blue. Then, the method of adjustment was used to determine the unique hues for the same three observers. A remarkable similarity was found between unique hues and illusory loci, suggesting that the illusion is due to a difference in the spatial resolution of the post-receptor channels producing the unique hues. PMID:17408717

Logvinenko, Alexander D; Hutchinson, Sara J



Carotenoid-based bill colour is an integrative signal of multiple parasite infection in blackbird  

NASA Astrophysics Data System (ADS)

In the study of parasite-mediated sexual selection, there has been controversial evidence for the prediction that brighter males should have fewer parasites. Most of these studies have focused on one parasite species. Our aim was to investigate the expression of carotenoid-based coloured signals in relation to patterns of multiple parasite infections, to determine whether colour reflects parasite load of all parasite species, or whether different relationships might be found when looking at each parasite species independently. We investigated the relationship between bill colour, body mass and plasma carotenoids and parasite load (feather chewing lice, blood parasite Plasmodium sp., intestinal parasites cestodes and coccidia) in the blackbird ( Turdus merula). Bill colour on its own appeared to be a poor predictor of parasite load when investigating its relationships with individual parasite species. Variation in parasite intensities at the community level was summarised using principal component analysis to derive synthetic indexes of relative parasite species abundance and absolute parasite load. The relative abundance of parasite species was strongly related to bill colour, plasma carotenoid levels and body mass: birds with relatively more cestodes and chewing lice and relatively less Plasmodium and coccidia had a more colourful bill, circulated more carotenoids and were heavier. These results suggest that bill colour more accurately reflects the relative intensities of parasite infection, rather than one-by-one relationships with parasites or absolute parasite burden. Investigating patterns of multiple parasite infection would thus improve our understanding of the information conveyed by coloured signals on parasite load.

Biard, Clotilde; Saulnier, Nicolas; Gaillard, Maria; Moreau, Jérôme



Molecular genetics of coat colour variations in White Galloway and White Park cattle.  


White Galloway cattle exhibit three different white coat colour phenotypes, that is, well marked, strongly marked and mismarked. However, mating of individuals with the preferred well or strongly marked phenotype also results in offspring with the undesired mismarked and/or even fully black coat colour. To elucidate the genetic background of the coat colour variations in White Galloway cattle, we analysed four coat colour relevant genes: mast/stem cell growth factor receptor (KIT), KIT ligand (KITLG), melanocortin 1 receptor (MC1R) and tyrosinase (TYR). Here, we show that the coat colour variations in White Galloway cattle and White Park cattle are caused by a KIT gene (chromosome 6) duplication and aberrant insertion on chromosome 29 (Cs29 ) as recently described for colour-sided Belgian Blue. Homozygous (Cs29 /Cs29 ) White Galloway cattle and White Park cattle exhibit the mismarked phenotype, whereas heterozygous (Cs29 /wt29 ) individuals are either well or strongly marked. In contrast, fully black individuals are characterised by the wild-type chromosome 29. As known for other cattle breeds, mutations in the MC1R gene determine the red colouring. Our data suggest that the white coat colour variations in White Galloway cattle and White Park cattle are caused by a dose-dependent effect based on the ploidy of aberrant insertions and inheritance of the KIT gene on chromosome 29. PMID:23418861

Brenig, B; Beck, J; Floren, C; Bornemann-Kolatzki, K; Wiedemann, I; Hennecke, S; Swalve, H; Schütz, E



Variation of total FOS, total IOS, inulin and their related-metabolizing enzymes in burdock roots ( Arctium lappa L.) stored under different temperatures  

Microsoft Academic Search

Burdock roots were stored for six weeks at three temperatures, 0, 15 and 20°C, and activity of sucrose hydrolase (SH), 1-kestose hydrolase (1-KH), inulin hydrolase (InH), sucrose:sucrose 1-fructosyltransferase (1-SST) and fructan:fructan 1-fructoslytransferase (1-FFT) were assessed. Simultaneously, total fructooligosaccharides (FOS), total inulooligosaccharides (IOS) and inulin were also assessed during storage. During storage, SH showed an irregular variation at 15 and 20°C,

Y. Ishiguro; S. Onodera; N. Benkeblia; N. Shiomi



Contribution by different fuels and metabolic pathways to the total ATP turnover of proliferating MCF-7 breast cancer cells.  

PubMed Central

For the past 70 years the dominant perception of cancer metabolism has been that it is fuelled mainly by glucose (via aerobic glycolysis) and glutamine. Consequently, investigations into the diagnosis, treatment and the basic metabolism of cancer cells have been directed by this perception. However, the data on cancer metabolism are equivocal, and in this study we have sought to clarify the issue. Using an innovative system we have measured the total ATP turnover of the MCF-7 breast cancer cell line, the contributions to this turnover by oxidative and glycolytic ATP production and the contributions to the oxidative component by glucose, lactate, glutamine, palmitate and oleate. The total ATP turnover over approx. 5 days was 26.8 micromol of ATP.10(7) cells(-1).h(-1). ATP production was 80% oxidative and 20% glycolytic. Contributions to the oxidative component were approx. 10% glucose, 14% glutamine, 7% palmitate, 4% oleate and 65% from unidentified sources. The contribution by glucose (glycolysis and oxidation) to total ATP turnover was 28.8%, glutamine contributed 10.7% and glucose and glutamine combined contributed 40%. Glucose and glutamine are significant fuels, but they account for less than half of the total ATP turnover. The contribution of aerobic glycolysis is not different from that in a variety of other non-transformed cell types.

Guppy, Michael; Leedman, Peter; Zu, XinLin; Russell, Victoria



Environmental and Genetic Effects on Pigment-Based vs. Structural Component of Yellow Feather Colouration  

PubMed Central

Background Carotenoid plumage is of widespread use in bird communication. Carotenoid-based feather colouration has recently been shown to be dependent on both pigment concentration and feather structure. If these two components are determined differently, one plumage patch may potentially convey different aspects of individual quality. Methodology/Principal Findings We evaluated the effects of genetic and environmental factors on carotenoid-based yellow breast colouration of Great Tit (Parus major) nestlings. By partial cross-fostering, we separated the genetic and pre-natal vs. post-natal parental effects on both the structural and the pigment-based component of carotenoid-based plumage colouration. We also simultaneously manipulated the post-hatching environment by brood size manipulation. The structural component of nestling colouration reflected features of female colouration. On the other hand, the pigment-based component was more affected by rearing conditions presumably representing food quality. While the structural component was related to both origin- and environment-related factors, the pigment-based component seemed to be environment-dependent only. These results support the notion that pigment-based and structural components of feather colouration are determined differently. Conclusions/Significance Chromatic and achromatic components of carotenoid-based feather colouration reflected different aspects of individual quality and history, and thus may potentially form a multicomponent signal.

Matrkova, Jana; Remes, Vladimir



Representing Object Colour in Language Comprehension  

ERIC Educational Resources Information Center

Embodied theories of cognition hold that mentally representing something "red" engages the neural subsystems that respond to environmental perception of that colour. This paper examines whether implicit perceptual information on object colour is represented during sentence comprehension even though doing so does not necessarily facilitate task…

Connell, Louise



Colour changes in bruised apple fruit tissue  

Microsoft Academic Search

A study of changes with time in aspects of bruise colour in ‘Granny Smith’ apples (Malus domestica) was undertaken in an attempt to identify the optimum time for assessment of bruise severity in experiments on apples. Bruised cortical tissue became darker (decreased lightness), browner (decreased hue angle), and increased in colour intensity (increased chroma) in the first few hours following

Waiss Samim; Nigel H. Banks



Modelling Ambient Systems with Coloured Petri Nets.  

National Technical Information Service (NTIS)

This paper is concerned with the formal modelling of Ambient Systems, focussing on the issues that emerge in their modelling using coloured Petri nets. A new class of coloured Petri nets, called Ambient Petri Nets (APNs), is introduced. Furthermore, a rel...

A. Konios M. Pietkiewicz-Koutny



Skin colour and bilirubin in neonates  

Microsoft Academic Search

The correlation between the yellow colour of the skin and serum bilirubin concentration, reserve albumin concentration, and pH was investigated in 76 icteric neonates. Significant linear correlation existed between yellow colour of the skin and serum bilirubin concentration, reciprocal of the reserve albumin concentration, and the squared hydrogen ion concentration. Furthermore, the basic yellowness of the skin at birth correlated

A Knudsen; R Brodersen



Quantitative Monitoring for Enhanced Geothermal Systems Using Double-Difference Waveform Inversion with Spatially-Variant Total-Variation Regularization  

SciTech Connect

Double-difference waveform inversion is a promising tool for quantitative monitoring for enhanced geothermal systems (EGS). The method uses time-lapse seismic data to jointly inverts for reservoir changes. Due to the ill-posedness of waveform inversion, it is a great challenge to obtain reservoir changes accurately and efficiently, particularly when using timelapse seismic reflection data. To improve reconstruction, we develop a spatially-variant total-variation regularization scheme into double-difference waveform inversion to improve the inversion accuracy and robustness. The new regularization scheme employs different regularization parameters in different regions of the model to obtain an optimal regularization in each area. We compare the results obtained using a spatially-variant parameter with those obtained using a constant regularization parameter. Utilizing a spatially-variant regularization scheme, the target monitoring regions are well reconstructed and the image noise is significantly reduced outside the monitoring regions. Our numerical examples demonstrate that the spatially-variant total-variation regularization scheme provides the flexibility to regularize local regions based on the a priori spatial information without increasing computational costs and the computer memory requirement.

Lin, Youzuo [Los Alamos National Laboratory; Huang, Lianjie [Los Alamos National Laboratory; Zhang, Zhigang [Los Alamos National Laboratory



QTL dissection of the loss of green colour during post-anthesis grain maturation in two-rowed barley.  


Ability to genetically manipulate the loss of green colour during grain maturation has potentials for increasing productivity, disease resistance, and drought and heat tolerance in crop plants. Two doubled haploid, two-rowed barley populations (Vlamingh × Buloke and VB9524 × ND11231*12) were monitored over 2 years for loss of green colour during grain filling using a portable active sensor. The aims were to determine the genomic regions that control trait heritability by quantitative trait locus (QTL) analysis, and to examine patterns of QTL-environment interactions under different conditions of water stress. In the Vlamingh × Buloke cross, broad-sense heritability estimate for loss of green colour (measured as the difference in sensor readings taken at anthesis and maturity, ?SRI) was 0.68, and 0.78 for the VB9524 × ND11231*12 population. In the VB9524 × ND11231*12 population, rapid loss of green colour was positively associated with grain yield and percent plump grains, but in the Vlamingh × Buloke population, a slower loss of green colour (low ?SRI) was associated with increased grain plumpness. With the aid of a dense array of single nucleotide polymorphisms (SNPs) and EST-derived SSR markers, a total of nine QTLs were detected across the two populations. Of these, a single major locus on the short arm of barley chromosome 5H was consistently linked with trait variation across the populations and multiple environments. The QTL was independent of flowering time and explained between 5.4 and 15.4 % of the variation observed in both populations, depending on the environment, and although a QTL × E interaction was detected, it was largely due to a change in the magnitude of the effect, rather than a change in direction. The results suggest that loss of green colour during grain maturation may be under the control of a simple genetic architecture, but a careful study of target populations and environments would be required for breeding purposes. PMID:23604470

Emebiri, Livinus C



Dwarf elliptical galaxies: structure, star formation and colour-magnitude diagrams  

NASA Astrophysics Data System (ADS)

The aim of this paper is to cast light on the formation and evolution of elliptical galaxies by means of N-body hydrodynamical simulations that include star formation, feedback and chemical evolution. Particular attention is paid to the case of dwarf spheroidals of the Local Group which, thanks to their proximity and modern ground-based and space instrumentation, can be resolved into single stars so that independent determinations of their age and star formation history can be derived. Indeed, the analysis of the colour-magnitude diagram of their stellar content allows us to infer the past history of star formation and chemical enrichment, thus setting important constraints on galactic models. Dwarf galaxies are known to exhibit complicated histories of star formation ranging from a single very old episode to a series of bursts over most of the Hubble time. By understanding the physical process driving star formation in these objects, we might be able to infer the mechanism governing star formation in more massive elliptical galaxies. Given these premises, we start from virialized haloes of dark matter, and follow the infall of gas into the potential wells and the formation of stars. We find that in objects of the same total mass, different star formation histories are possible, if the collapse phase started at different initial densities. We predict the final structure of dwarf spheroidal galaxies, their kinematics, their large-scale distribution of gas and stars, and their detailed histories of the star formation and metal enrichment. Using a population synthesis technique, star formation and metal enrichment rates are then adopted to generate the present colour-magnitude diagrams of the stellar populations hosted by dwarf spheroidal galaxies. The simulations are made assuming the redshift of galaxy formation zfor=5 and varying the cosmological parameters H0 and q0. The resulting colour-magnitude diagrams are then compared with the observational ones for some dwarf spheroidals of the Local Group.

Carraro, Giovanni; Chiosi, Cesare; Girardi, Léo; Lia, Cesario



Validation of Different Methods of Preparation of Adhatoda vasica Leaf Juice by Quantification of Total Alkaloids and Vasicine  

PubMed Central

Leaf of Adhatoda vasica (Vasaka) is an important drug of Ayurveda, prescribed as an expectorant. Quinazoline alkaloids present in the leaves are established as active principles. In Ayurveda, its leaf juice (Vasa swarasa) is incorporated in many formulations. Classical method for extracting the juice (swarasa) from the leaf is an elaborate process, which involves subjecting a bolus of crushed fresh leaf to heat followed by squeezing out the juice. Commercially, to prepare the juice of Vasaka, manufacturers have been adopting different methods other than the traditional method. In an effort to evaluate these modified processes phytochemically to identify the process which gives juice of the quality that is obtained by traditional method, in terms of its alkaloid content, we prepared the leaf juice by traditional Ayurvedic method, its modification by steaming of leaf to simulate the traditional method and other methods adopted by some manufacturers. These juice samples were evaluated for the total alkaloid content by spectrophotometric method and vasicine content by thin layer chromatography densitometric method using high performance thin layer chromatography. The high performance thin layer chromatography method was validated for precision, repeatability and accuracy. The total alkaloid content varied from 0.3 mg/ml to 5.93 mg/ml and that of vasicine content varied from 0.2 mg/ml to 5.64 mg/ml in the juice samples prepared by different methods. The present study revealed that steaming of fresh leaves under 15 lb pressure yielded same quantity of juice as the traditional bolus method (25 ml/100 g leaf) and its total alkaloid content and vasicine content (4.05±0.12 and 3.46±0.06 mg/ml, respectively) were very high when compared to the other methods, though the traditional method was found to give the best quality juice with highest amount of total alkaloids (5.93±0.55 mg/ml) and vasicine (5.64±0.10 mg/ml) content.

Soni, S.; Anandjiwala, Sheetal; Patel, G.; Rajani, M.



Validation of Different Methods of Preparation of Adhatoda vasica Leaf Juice by Quantification of Total Alkaloids and Vasicine.  


Leaf of Adhatoda vasica (Vasaka) is an important drug of Ayurveda, prescribed as an expectorant. Quinazoline alkaloids present in the leaves are established as active principles. In Ayurveda, its leaf juice (Vasa swarasa) is incorporated in many formulations. Classical method for extracting the juice (swarasa) from the leaf is an elaborate process, which involves subjecting a bolus of crushed fresh leaf to heat followed by squeezing out the juice. Commercially, to prepare the juice of Vasaka, manufacturers have been adopting different methods other than the traditional method. In an effort to evaluate these modified processes phytochemically to identify the process which gives juice of the quality that is obtained by traditional method, in terms of its alkaloid content, we prepared the leaf juice by traditional Ayurvedic method, its modification by steaming of leaf to simulate the traditional method and other methods adopted by some manufacturers. These juice samples were evaluated for the total alkaloid content by spectrophotometric method and vasicine content by thin layer chromatography densitometric method using high performance thin layer chromatography. The high performance thin layer chromatography method was validated for precision, repeatability and accuracy. The total alkaloid content varied from 0.3 mg/ml to 5.93 mg/ml and that of vasicine content varied from 0.2 mg/ml to 5.64 mg/ml in the juice samples prepared by different methods. The present study revealed that steaming of fresh leaves under 15 lb pressure yielded same quantity of juice as the traditional bolus method (25 ml/100 g leaf) and its total alkaloid content and vasicine content (4.05+/-0.12 and 3.46+/-0.06 mg/ml, respectively) were very high when compared to the other methods, though the traditional method was found to give the best quality juice with highest amount of total alkaloids (5.93+/-0.55 mg/ml) and vasicine (5.64+/-0.10 mg/ml) content. PMID:20390078

Soni, S; Anandjiwala, Sheetal; Patel, G; Rajani, M



Fire severity effects on ash extractable Total Phosphorous  

NASA Astrophysics Data System (ADS)

Phosphorous (P) is a crucial element to plant nutrition and limits vegetal production. The amounts of P in soil are lower and great part of this nutrient is absorbed or precipitated. It is well known that fire has important implications on P cycle, that can be lost throughout volatilization, evacuated with the smoke, but also more available to transport after organic matter mineralization imposed by the fire. The release of P depends on ash pH and their chemical and physical characteristics. Fire temperatures impose different severities, according to the specie affected and contact time. Fire severity is often evaluated by ash colour and this is a low-cost and excellent methodology to assess the fire effects on ecosystems. The aim of this work is study the ash properties physical and chemical properties on ash extractable Total Phosphorous (TP), collected in three wildfires, occured in Portugal, (named, (1) Quinta do Conde, (2) Quinta da Areia and (3) Casal do Sapo) composed mainly by Quercus suber and Pinus pinaster trees. The ash colour was assessed using the Munsell color chart. From all three plots we analyzed a total of 102 ash samples and we identified 5 different ash colours, ordered in an increasing order of severity, Very Dark Brown, Black, Dark Grey, Very Dark Grey and Light Grey. In order to observe significant differences between extractable TP and ash colours, we applied an ANOVA One Way test, and considered the differences significant at a p<0.05. The results showed that significant differences in the extractable TP among the different ash colours. Hence, to identify specific differences between each ash colour, we applied a post-hoc Fisher LSD test, significant at a p<0.05. The results obtained showed significant differences between the extractable TP from Very dark Brown and Black ash, produced at lower severities, in relation to Dark Grey, Very Dark Grey and Light Grey ash, generated at higher severities. The means of the first group were higher than the observed in the second one. This indicates that ash produced lower temperatures release in solution higher amounts of TP. These divergences occur due temperature of combustion, affected specie, ash pH values and CaCO3 content, which affects the quantity of this element in solution. Discussions about these effects will be accurate in the communication.

Pereira, Paulo; Úbeda, Xavier; Martin, Deborah



The formation of colour during biological treatment of pulp and paper wastewater.  


Colour discharges are gaining renewed focus in the pulp and paper industry as increasingly strict regulatory limits are placed on wastewater quality and aesthetics. In-mill process improvements, such as ECF bleaching and oxygen delignification, have decreased wastewater colour loadings. However, a survey of 12 pulp and paper mill systems found that effluent treatment using aerated stabilisation basins (ASB) leads to average increases in colour of 20-40%. In some instances, this phenomenon may even double the influent colour levels. Activated sludge systems did not produce a colour increase. The measured increases that follow ASB secondary treatment may be sufficient for a mill to fail prescribed discharge standards. A detailed field survey focusing on sections of an integrated bleached kraft mill ASB treatment system was undertaken. The average increase in colour at the final point of discharge was 45%. The major changes in colour concentration occurred in the inlet to the main treatment pond, and in polishing ponds that followed the main treatment pond. Both of these areas receive little or no aeration. No significant change was observed in the highly aerated main pond. These results, along with literature reports, suggested that redox conditions play a major role in influencing colour behaviour. To test this, two series of paired continuously stirred reactors were used to treat whole mill effluent from two ECF bleached kraft mills in parallel. The first series initially treated under anaerobic conditions, followed by an aerobic reactor, while the second series reversed this order. With the initial anaerobic stage, effluent colour increased by 18% and 19% for the first and second series respectively. Subsequent treatment by aerobic bacteria further increased colour by 14% and 6%, for a total increase of 32% and 25%. Initial aerobic treatment, however, did not lead to any significant change in colour for either effluent. Further anaerobic treatment following aerobic conditions produced only small increases in colour. These results are consistent with the ASB and activated sludge system survey, suggesting that anaerobic conditions at the head of treatment systems initiate the observed increases in effluent colour in ASB treatment systems. PMID:15461402

Milestone, C B; Fulthorpe, R R; Stuthridge, T R



User preferences in colour enhancement for unsupervised printing methods  

NASA Astrophysics Data System (ADS)

In order to obtain a good quality image in preparation for inkjet printing, the process of adjusting images can be a time consuming and a costly procedure. In this paper, we consider the use of an unsupervised colour enhancement method as part of the automatic pre-processors for printing. Other unsupervised colour enhancement methods are utilised and compared: Retinex, RSR, ACE, Histogram Equalisation, Auto Levels. Test images are subjected to all of the enhancement methods, which are then printed. Users are asked compare each of the sampled images. In all cases, the results are dependent on the image. Thus, we have selected a range of test images: photographs of scenes, reproduction of prints, paintings and drawings. Some of the tested methods are parameter dependent. We do not intend to consider fine tuning for each of the techniques, rather to consider an average parameter set for each one and then test if this approach can aid the decision process of fine tuning. Three user groups are employed: the general user, commercial photographer expert and fine artist. Groups are asked to make a blind evaluation of a range of images (the original and the colour enhanced by the different methods); these are randomly placed. All images are printed on the same printer using the same settings. Users are asked to identify their preferred print in relation to lightness, tonal range, colour range, quality of detail and overall subjective preference.

Parraman, Carinna; Rizzi, Alessandro



FIR colours and SEDs of nearby galaxies observed with Herschel  

NASA Astrophysics Data System (ADS)

We present infrared colours (in the 25-500 ?m spectral range) and UV to radio continuum spectral energy distributions of a sample of 51 nearby galaxies observed with SPIRE on Herschel. The observed sample includes all morphological classes, from quiescent ellipticals to active starbursts. Active galaxies have warmer colour temperatures than normal spirals. In ellipticals hosting a radio galaxy, the far-infrared (FIR) emission is dominated by the synchrotron nuclear emission. The colour temperature of the cold dust is higher in quiescent E-S0a than in star-forming systems probably because of the different nature of their dust heating sources (evolved stellar populations, X-ray, fast electrons) and dust grain properties. In contrast to the colour temperature of the warm dust, the f350/f500 index sensitive to the cold dust decreases with star formation and increases with metallicity, suggesting an overabundance of cold dust or an emissivity parameter ? < 2 in low metallicity, active systems. Herschel is an ESA space observatory with science instruments provided by Principal Investigator consortia. It is open for proposals for observing time from the worldwide astronomical community.

Boselli, A.; Ciesla, L.; Buat, V.; Cortese, L.; Auld, R.; Baes, M.; Bendo, G. J.; Bianchi, S.; Bock, J.; Bomans, D. J.; Bradford, M.; Castro-Rodriguez, N.; Chanial, P.; Charlot, S.; Clemens, M.; Clements, D.; Corbelli, E.; Cooray, A.; Cormier, D.; Dariush, A.; Davies, J.; de Looze, I.; di Serego Alighieri, S.; Dwek, E.; Eales, S.; Elbaz, D.; Fadda, D.; Fritz, J.; Galametz, M.; Galliano, F.; Garcia-Appadoo, D. A.; Gavazzi, G.; Gear, W.; Giovanardi, C.; Glenn, J.; Gomez, H.; Griffin, M.; Grossi, M.; Hony, S.; Hughes, T. M.; Hunt, L.; Isaak, K.; Jones, A.; Levenson, L.; Lu, N.; Madden, S. C.; O'Halloran, B.; Okumura, K.; Oliver, S.; Page, M.; Panuzzo, P.; Papageorgiou, A.; Parkin, T.; Perez-Fournon, I.; Pierini, D.; Pohlen, M.; Rangwala, N.; Rigby, E.; Roussel, H.; Rykala, A.; Sabatini, S.; Sacchi, N.; Sauvage, M.; Schulz, B.; Schirm, M.; Smith, M. W. L.; Spinoglio, L.; Stevens, J.; Sundar, S.; Symeonidis, M.; Trichas, M.; Vaccari, M.; Verstappen, J.; Vigroux, L.; Vlahakis, C.; Wilson, C.; Wozniak, H.; Wright, G.; Xilouris, E. M.; Zeilinger, W.; Zibetti, S.



Effect of spatial uncertainty and familiarity on memory for surface colour in natural scenes and Mondrian patterns  

Microsoft Academic Search

How does memory affect surface-colour matching and is there any advantage with familiar scenes? A computer- controlled colour display system was used to present images of natural scenes and Mondrian patterns under two different daylights of correlated colour temperatures 25000 K and 6500 K, each lasting 1 s and separated by an interval lasting 0, 0.1, 0.2, 0.5, 1, 2,

Kinjiro Amano; David H. Foster



Comparison of the standard and computerized versions of the Raven Coloured Progressive Matrices Test.  


Computerized psychological assessment is potentially a viable alternative to the traditional method of examiner based assessment. 15 children, 4 females and 11 males, ranging in age from 7 to 14 yr., were administered a computerized version of the Raven's Coloured Progressive Matrices test. The necessary software for computerizing this test was developed and programmed for use with an Apple II Plus microcomputer. Scores obtained from the computerized and traditional versions of the Raven's test were compared on total mean score, correlation with the WISC-R, Raven's subscale intercorrelations, and Raven's total mean score composition. In general, results indicate that the two versions of the Raven's Matrices do not statistically significantly differ on the dimensions tested in the present study. The relatively small number of subjects and the lack of rigorous experimental control limit generalization of the results. Continued research into the use of computerized psychological assessment is warranted. PMID:7063353

Rock, D L; Nolen, P A



Tooth, skin, hair and eye colour interrelationships in Greek young adults.  


The purpose of this study was to investigate the possible interrelationships of teeth, skin, eye and hair colour. A portable colorimeter (Shade Eye NCC/Shofu) was used to record the colour in the CIELAB system of the upper right incisors in 150 dental school students, along with their skin colour at three different areas. Natural hair and eye colour was classified into several categories by a trained examiner (ICC 0.93-0.99). One-way ANOVA and correlation tests were used to statistically analyse the data. Skin was found to have significantly higher L*, b* but lower a* values than teeth (p < 0.05). A significant correlation (p < 0.05) of teeth to skin L* and a*colour coordinate was found, but not to b* coordinate (p > 0.05). Hair tones were not correlated to teeth L* or b*, but only to a*coordinate. Teeth and eye colour coordinates were not correlated (p > 0.05). Eye and hair tones were found to have the highest significant correlation (? = 0.369). In conclusion, teeth of this cohort were found to be lighter, less red and yellow than the skin. Teeth colour was not related to eye colour, but lighter teeth were found to be associated with lighter skins, and redder lateral incisors to lighter hair. Darker facial skins or yellower forehead areas were also associated with darker hair and vice versa. The clinical relevance of the study is that the investigated facial characteristics are inter-correlated weakly to moderately, and for this reason predicting the colour parameters of one facial characteristic by another would not be accurate, but helpful for a rough colour selection as associations show. PMID:22349932

Lagouvardos, Panagiotis E; Tsamali, Ioana; Papadopoulou, Christine; Polyzois, Gregory



Colour and stability assessment of blue ferric anthocyanin chelates in liquid pectin-stabilised model systems.  


The formation of blue coloured ferric anthocyanin chelates and their colour stability during storage and thermal treatment were monitored in a pH range relevant to food (3.6-5.0). Liquid model systems were composed of different types of Citrus pectins, juices (J) and the respective phenolic extracts (E) from elderberry (EB), black currant (BC), red cabbage (RC) and purple carrot (PC) in the presence of ferric ions. For EB, BC and PC, pure blue colours devoid of a violet tint were exclusively observed for the phenolic extracts and at pH values ? 4.5 in model systems containing high methoxylated and amidated pectins, respectively. Colour and its stability strongly depended on the amount of ferric ions and the plant source; however, colour decay could generally be described as a pseudo-first-order kinetics. Despite optimal colour hues for RC-E and RC-J, storage and heat stabilities were poor. Highest colour intensities and best stabilities were observed for model systems containing PC-E at a molar anthocyanin:ferric ion ratio of 1:2. Ascorbic and lactic acids interfered with ferric ions, thus significantly affecting blue colour evolution and stability. Colour loss strongly depended on heat exposure with activation energies ranging between 60.5 and 78.4 kJ/mol. The comprehensive evaluation of the interrelationship of pigment source, pH conditions and pectin type on chelate formation and stability demonstrated that ferric anthocyanin chelates are promising natural blue food colourants. PMID:23411339

Buchweitz, M; Brauch, J; Carle, R; Kammerer, D R



Involvement of hepatic IL-1 in the strain-dependent sex differences in serum total cholesterol levels in rats.  


The strain and sex differences in serum total cholesterol (TC) levels were examined in F344 and Sprague-Dawley (SD) rats. A sex difference (maledifference (maledifference in hepatic HMGR gene expression was closely correlated with the levels of hepatic interleukins (ILs), especially of IL-1?, which acts as a positive regulator for the hepatic HMGR gene. Hepatic IL-1? protein expression was higher in female F344 rats than in male F344 rats and compared with male and female SD rats. Similar to hepatic IL-1? protein expression, serum TC levels were highest in female F344 rats than in the other groups of rats. Serum TC and hepatic IL-1? levels in male F344 rats were similar to those in male and female SD rats. The present findings demonstrate for the first time that strain-dependent sex difference in serum TC level between F344 and SD rats is, at least in part, related to difference in the IL-1?-mediated HMGR gene expression level in the liver. PMID:24694611

Kumagai, Yoichi; Sekimoto, Masashi; Okamoto, Minako; Kurita, Ryuzo; Kojima, Misaki; Degawa, Masakuni



Local versus total systemic bioavailability as a means to compare different inhaled formulations of the same substance.  


For inhaled formulations of a drug substance, the balance between desired local activity and undesired systemic activity can be expressed with an L:T ratio, where L stands for the local bioavailability and T stands for the total systemic bioavailability. The L:T ratio depends not only on the ability of the different devices to divide the delivered dose between the lungs and the oropharynx but also on the inherent difference in gastrointestinal (GI) first-pass metabolism between different substances. The L:T ratio should therefore not be used to make comparisons across different drug substances but only to compare the same drug formulated in different inhalation systems. A high L:T ratio expresses a good targeting ability of the combination of substance and device or a low contribution from the GI tract. A high L:T ratio also reflects a more beneficial balance between wanted and unwanted effects. The L:T ratio was calculated from literature data for a number of salbutamol (albuterol) formulations and for two budesonide and two terbutaline formulations. For salbutamol, values ranged from 0.15 to 0.55 with different devices. For budesonide, the values ranged from 0.66 to 0.85, and for terbutaline, the values ranged from 0.59 to 0.79. The L:T ratio can thus be used to aid in the choice of inhaler. PMID:10177220

Borgström, L



Analysis of colour stability of selected provisional prosthetic materials: an in vitro study.  


Prosthetic restorative materials (that are) used for temporary fixed dentures tend to exhibit variable discolouration over several weeks of use. The aim of this study was to perform a spectrophotometric analysis of the influence of selected discolouring factors on the colour stability of provisional prosthetic materials in vitro. In the study, the following prosthetic materials for short-term use in the oral cavity were evaluated: Luxatemp, Structur 2S.C., Protemp II, Zhermacryl STC and Dentalon Plus. Samples of these materials were immersed in coffee, tea and dark fruit juice for 60 h at different pH values. Colour was evaluated by determining the monochromatic coefficients of light reflected by the samples, using a spectrophotometric method. Results received in artificial light (illuminant A) were compared with those obtained in daylight (illuminant D65). Changes in colour and its parameters according to the CIE L*a*b* system were analysed. The analysis (of the colour and colour parameters) of the tested materials in two types of light showed that Structur displayed the greatest tendency to discolouration and that the least tendency to discolouration was exhibited by Dentalon Plus. The fact that colour parameters obtained in two types of light were not identical suggests that changes in the colour of the same material may be perceived differently, depending on the illuminant. Provisional prosthetic materials show variable colour stability under different conditions in the oral cavity. The colour of prosthetic materials may be perceived differently, depending on the illuminant and the effect of the environment in which they are used. PMID:19594399

Koczorowski, Ryszard; Linkowska-Swidzi?ska, Kamila; Gedrange, Tomasz; Swidzi?ski, Teodor



Correlation between shell colour and ultrastructure in pheasant eggs.  


1. The histochemistry and ultrastructure of pheasant eggs were compared on the basis of blue or brown shell colour. 2. Differences in lectin histochemistry of the outer shell membrane calcification surface indicate a biochemical disruption of the calcification sites in blue eggs. 3. Significant differences were observed in all aspects of eggshell ultrastructure with blue eggs having thinner shells with structural defects. 4. Poor hatchability of blue eggs may reflect high rates of weight loss associated with a defective eggshell. PMID:11469553

Richards, P D; Deeming, D C



Total and inorganic arsenic concentrations in different species of economically important algae harvested from coastal zones of Chile.  


Chile is one of the major producers of phytocolloids extracted from seaweed. Multicellular algae are considered to be primary accumulators of arsenic. We analyzed 14 species of algae belonging to the groups Rhodophyceae (10), Phaeophyceae (3) and Chlorophyceae (1) from different coastal zones of Chile in 2003-2004. Dry ashing mineralization (for total As) and acid digestion (for inorganic As) together with quantification by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS) were employed. In general, total arsenic concentrations varied between 3.0 and 68 mg kg(-1), whereas inorganic arsenic concentrations ranged between 0.15 and 1.06 mg kg(-1). The algal species Durvillaea antarctica and Porphyra columbina, used for direct human consumption, did not have inorganic arsenic levels that represent a health risk to consumers. Among species used for phytocolloids production, such as Macrocystis piryfera, Gracilaria chilensis and Gigartina skottsbergii, observed levels of inorganic arsenic were greater than 1 mg kg(-1), the limit value established by the regulations of some countries. Among the 14 species of algae tested, inorganic arsenic levels were between 0.8% and 13% of the total arsenic concentrations; that is, arsenic present in these algae was found primarily as organic arsenic. PMID:22138359

Díaz, Oscar; Tapia, Yasna; Muñoz, Ociel; Montoro, Rosa; Velez, Dinoraz; Almela, Concepción



The effects of mouthrinses on microhardness and colour stability of aesthetic restorative materials.  


Detrimental effects exerted on oral and dental tissues by frequent mouthrinse use are observed, but studies about their effects on aesthetic restorative materials are limited. In this study, the purpose was to examine the effects of three proprietary mouthrinses on three different aesthetic restorative materials. Mouthrinses were used as treatment groups, while distilled water served as the control. From a total of 72 specimens, each experimental group consisting of 24 samples were prepared from each restorative test material by using metal moulds. The samples were stored in 20 mL of one of the mouthrinses for 12 h, which was reported as the equivalent time to 1 year of 2-min daily mouthrinse use. Changes between baseline and after treatment measurements of surface microhardness and colour of the test materials were established by using Vickers microhardness tester and spectrophotometer. Statistical analyses were performed by analysis of variance (anova), with Bonferroni correction. The level of significance was set as 0.05 in all tests. There were no significant interactions between the test solutions and the test materials with regard to microhardness (P > 0.05), and colour changes of the materials (P > 0.05). Effects of mouthrinses on restorative materials may differ depending on many in vivo factors that could not be replicated in vitro. Therefore, routine assessment of the effects of mouthrinses on aesthetic restorative materials is recommended. PMID:12366588

Gürdal, P; Akdeniz, B Günz; Hakan Sen, B



Physicochemical and physiological basis of dichromatic colour  

NASA Astrophysics Data System (ADS)

Out of three perceptual characteristics of the colour of any substance, the hue depends mostly on the spectral properties of a substance, while the brightness and saturation depend also on the concentration of a substance and its thickness. Here, we report that evident change of the hue of the colour (i.e., from green to red) is due to a change in concentration or the thickness of a layer in some exceptional substances such as pumpkin seed oil or an aqueous solution of bromophenol blue. In some regions of Central Europe, salad dressing is made preferably with the pumpkin seed oil, which has a strong characteristic nut-like taste and remarkable properties of the colour: it appears red in a bottle, but green when served as a salad dressing. The colour of the pumpkin seed oil was previously described as brownish yellow, dark green, dark green to red ochre or dark reddish brown to light yellow green. We elucidated the physicochemical and physiological basis of such dichromatism by Beer-Lambert law and by the characteristics of human colour perception. Our concept was corroborated by the outcome of calculations of colour from spectral properties using colour matching functions. We found that dichromatism is observed if the absorption spectrum of any substance has at least two local minima: one wide but shallow and one narrow but deep local minimum.

Kreft, Samo; Kreft, Marko



Sensory and motor involvement in the enhanced redundant target effect: A study comparing anterior- and totally split-brain individuals  

Microsoft Academic Search

This study investigated the redundant target effect (RTE) in partial split-brain (anterior section sparing the splenium), total split-brain, and neurologically intact individuals. All completed an RTE protocol in which targets were presented on the midline or in an inter- or intrahemispheric manner. Stimuli of different nature (luminance, equiluminant colour, and global motion) were used separately in three experiments in order

Catherine Ouimet; Pierre Jolicœur; Jeff Miller; Alexia Ptito; Aldo Paggi; Nicoletta Foschi; Andrea Ortenzi; Maryse Lassonde



Effects of dietary red pepper on egg yolk colour and histological intestinal morphology in laying hens.  


To evaluate the effect of three kinds of red pepper supplementation 'Kagawa Hontaka' produced at Shiwaku Islands (KHS), Miki (KHM) and Takanotsume (TKT) on production performance, egg quality and intestinal histology in laying hens. A total of 32 laying hens (39?weeks of age) were randomly allotted to four groups, each comprising eight hens. Birds were fed a basal diet supplemented with red pepper at 0% (control), 0.5% KHS, 0.5% KHM and 0.5% TKT, respectively. Compared with the control group, no significant difference (p?>?0.05) in feed consumption, final body weight, hen-day production, egg mass, feed efficiency, shell-breaking strength, shell thickness, shell ratio, albumen ratio, yolk ratio and Haugh units was observed among the experimental groups. Roche yolk colour fan (RYCF) value increased significantly in all experimental groups (p?colour, redness (a*) and yellow index (YI) values were higher in the KHS and KHM groups (p?colour. PMID:23033816

Lokaewmanee, K; Yamauchi, K; Okuda, N



Why `false' colours are seen by butterflies  

NASA Astrophysics Data System (ADS)

Light can be described by its intensity, spectral distribution and polarization, and normally a visual system analyses these independently to extract the maximum amount of information. Here I present behavioural evidence that this does not happen in butterflies, whose choice of oviposition substrate on the basis of its colour appears to be strongly influenced by the direction of polarization of the light reflected from the substrate. To my knowledge, this is the first record of `false' colours being perceived as a result of light polarization. This detection of false colours may help butterflies to find optimal oviposition sites.

Kelber, Almut



Sources of Differences in On-Orbit Total Solar Irradiance Measurements and Description of Proposed Laboratory Intercomparison  

NASA Technical Reports Server (NTRS)

There is a 5 W/sq m (about 0.35 %) difference between current on-orbit Total Solar Irradiance (TSI) measurements. On 18-20 July 2005, a workshop was held at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland that focused on understanding possible reasons for this difference, through an examination of the instrument designs, calibration approaches, and appropriate measurement equations. The instruments studied in that workshop included the Active Cavity Radiometer Irradiance Monitor III (ACRIM III) on the Active Cavity Radiometer Irradiance Monitor SATellite (ACRIMSAT), the Total Irradiance Monitor (TIM) on the Solar Radiation and Climate Experiment (SORCE), the Variability of solar IRradiance and Gravity Oscillations (VIRGO) on the Solar and Heliospheric Observatory (SOHO), and the Earth Radiation Budget Experiment (ERBE) on the Earth Radiation Budget Satellite (ERBS). Presentations for each instrument included descriptions of its design, its measurement equation and uncertainty budget, and the methods used to assess on-orbit degradation. The workshop also included a session on satellite- and ground-based instrument comparisons and a session on laboratory-based comparisons and the application of new laboratory comparison techniques. The workshop has led to investigations of the effects of diffraction and of aperture area measurements on the differences between instruments. In addition, a laboratory-based instrument comparison is proposed that uses optical power measurements (with lasers that underEll the apertures of the TSI instruments), irradiance measurements (with lasers that overfill the apertures of the TSI instrument), and a cryogenic electrical substitution radiometer as a standard for comparing the instruments. A summary of the workshop and an overview of the proposed research efforts are presented here.

Butler, J.J.; Johnson, B. C.; Rice, J. P.; Shirley, E. L.; Barnes, R.A.



Survival of Brown Colour in Diamond During Storage in the Subcontinental Lithospheric Mantle  

NASA Astrophysics Data System (ADS)

Brown is the most common colour of natural diamond. This colour is generally associated with plastic deformation of the crystal structure, which is imparted during residence in the mantle. Dislocation movement generates vacancies, which aggregate into clusters of perhaps 30-60 vacancies. The resulting electronic configuration leads to the broad, featureless absorption pattern associated with common brown colour. It is well-established that the common brown colour can be removed by high-pressure-high-temperature (HPHT) treatment. The process involves pressures and temperatures in the range of 5-9 GPa and 1800-2700 ° C, respectively. The treatment may take several minutes or hours. It has been suggested that the same colour removal process operates continuously in the subcontinental lithospheric mantle, causing any brown diamonds in the diamond window to quickly lose their colour. The present study examined the validity of this suggestion. Temperature is the important difference between HPHT conditions and diamond window conditions. Higher temperatures result in faster colour removal. HPHT treatment occurs at 1800-2700 ° C, whereas inclusion thermometry places most lithospheric diamonds in the range of 900-1400 ° C. Destruction of the brown colour centre involves breaking up vacancy clusters. How quickly this can be done depends on the concentration of clusters as well as the rate constant. The rate constant is changes with temperature, according to the Arrhenius equation. The key to this relationship is the activation energy required for the breakup of a vacancy cluster. This activation energy can be estimated as the energy of an isolated monovacancy, minus the energy per vacancy of the cluster, plus the vacancy migration energy. A value of 7.7±0.3 eV is obtained using data from recent literature. For any given brown diamond, the rate constant determines the time needed to remove a certain amount of colour. The Arrhenius equation can be rearranged to show how this reaction time varies with temperature. Thus, the activation energy can be used in conjunction with experimental HPHT data to extrapolate reaction times from HPHT temperatures to lithospheric mantle temperatures. For a certain reduction in brown colour produced by HPHT (T1, t1), the equation below shows the time required (t2) to produce the same reduction at a different temperature (T2): ln(t2) = ln(t1) + (Ea/k)(1/T2-1/T1) where Ea is activation energy, k is the Boltzmann constant, and temperatures are in kelvins. The error in activation energy causes large, increasing error as the temperature difference between T1 and T2increases. Nevertheless, the time required to destroy brown colour in the lithospheric mantle is significant at the scale of geological time. Brown diamonds should easily maintain brown colour during cooler mantle storage at or below 1000 ° C. Warmer temperatures toward the base of the lithosphere may be able to reduce or eliminate brown colour within a reasonable geological time frame. However, the survival of brown colour in the lithospheric mantle does not require the colour to be formed late in the storage history nor does it require metastable storage in the graphite stability field. Additionally, preliminary measurements of diamond crystal strain suggest that brown colour removal in the lithospheric mantle is, at least, not a common occurrence. Mosaic spreading was gauged in 18 untreated natural diamonds using micro-X-ray diffraction (?XRD) ?-dimension peak widths. None of the colourless diamonds examined have a large residual mosaic spread, as should be expected for a diamond that has been deformed and turned brown, but later lost its brown colour. Despite the limited sample size, the results support some capacity for the survival of brown colour in the mantle.

Smith, Evan; Helmstaedt, Herwart; Flemming, Roberta



Colour change of soft denture liners after storage in coffee and coke.  


This study was to evaluate the colour change of soft denture liners after thermocycling and storage in coffee and coke. Four liners, two silicone-based (Sofreliner S and Reline GS) and two acrylic resin-based (Soft Confort and Dentuflex), were evaluated in this study. Ten samples were obtained for each group. After 2000 cycles of thermocycling with baths of 5°C and 55°C, five samples were stored in coffee and the remaining samples in coke. The colour alteration was evaluated in a reflection spectrophotometer before and after thermocycling, and after 1, 3, 24, 48 and 96h of storage in coffee and coke. Data were submitted to anova and Tukey's HSD test (?=0.05). Thermocycling and storage period represented a higher statistically significant influence for the resin liners than for the silicone materials. Coke did not influence the colour stability of the materials during storage. However, the coffee solution generated statistically significant colour alteration in the material Soft Confort. In the comparison between the coffee and coke solutions, there was no statistically significant difference for colour alteration only for the material Dentuflex. The silicone liners presented better colour stability following thermocycling and storage independent of the solution. The coffee solution was a statistically significant factor for colour alteration of the material Soft Confort. PMID:20082643

Goiato, Marcelo Coelho; Zuccolotti, Bruna Carolina Rossatti; Moreno, Amália; dos Santos, Daniela Micheline; Pesqueira, Aldiéris Alves; Dekon, Stefan Fiuza de Carvalho



On the roles of colour and scent in a specialized floral mimicry system  

PubMed Central

Background and Aims Sexually deceptive orchids achieve cross-pollination by mimicking the mating signals of female insects, generally hymenopterans. This pollination mechanism is often highly specific as it is based primarily on the mimicry of mating signals, especially the female sex pheromones of the targeted pollinator. Like many deceptive orchids, the Mediterranean species Ophrys arachnitiformis shows high levels of floral trait variation, especially in the colour of the perianth, which is either green or white/pinkinsh within populations. The adaptive significance of perianth colour polymorphism and its influence on pollinator visitation rates in sexually deceptive orchids remain obscure. Methods The relative importance of floral scent versus perianth colour in pollinator attraction in this orchid pollinator mimicry system was evaluated by performing floral scent analyses by gas chromatography-mass spectrometry (GC-MS) and behavioural bioassays with the pollinators under natural conditions were performed. Key Results The relative and absolute amounts of behaviourally active compounds are identical in the two colour morphs of O. arachnitiformis. Neither presence/absence nor the colour of the perianth (green versus white) influence attractiveness of the flowers to Colletes cunicularius males, the main pollinator of O. arachnitiformis. Conclusion Chemical signals alone can mediate the interactions in highly specialized mimicry systems. Floral colour polymorphism in O. arachnitiformis is not subjected to selection imposed by C. cunicularius males, and an interplay between different non-adaptive processes may be responsible for the maintenance of floral colour polymorphism both within and among populations.

Vereecken, Nicolas J.; Schiestl, Florian P.



Effects of extraction temperature on the phenolic and parthenolide contents, and colour of aqueous feverfew ( Tanacetum parthenium) extracts  

Microsoft Academic Search

The aim of this study was to determine the effects of extraction temperature on the colour as well as on the phenolic and parthenolide content of feverfew (Tanacetum parthenium) aqueous extracts, with a view to incorporating the extracts into a beverage. Results showed that extraction temperatures of 20–70°C yielded dark-coloured extracts with low total phenol and a relatively high total

Eunice N. Marete; Jean Christophe Jacquier; Dolores O’Riordan



Limited waterborne acute toxicity of native polycyclic aromatic compounds from coals of different types compared to their total hazard potential.  


Coals contain native polycyclic aromatic compounds (PACs), which include polycyclic aromatic hydrocarbons (PAHs), and heterocyclic aromatic compounds (NSO-PACs) in considerably varying amounts up to 2500 mg/kg. Whereas PAC bioavailability and toxicity from coals are generally considered to be low, few studies have considered potential variations arising from the composition of different coal types including native PAC content. In the present study, fine particles of different coal types exhibiting variable properties were systematically investigated regarding their PAC bioavailability. PAH content reached up to 79 mg/kg EPA-PAH and 865 mg/kg total PAH. Determination of the toxic potential of extracted PACs in bioassays showed inhibition of Caenorhabditis elegans reproduction (up to 94%) and increased mortality of Danio rerio embryos (up to 100%) after exposure to extracts from lignite, sub-bituminous, and bituminous coals. Anthracite extracts showed no effects. Contact assays using whole coal samples revealed no toxicity to D. rerio embryos in any of the coal samples, suggesting low bioavailability of PACs. In contrast, C. elegans reproduction was inhibited by direct coal contact; however, the observed toxicity probably resulted from other coal effects. The results suggest that despite the high toxic potential of PACs present, their bioavailability from different coal types is very limited and independent of coal properties and native PAH content. PMID:24024738

Meyer, Wiebke; Seiler, Thomas-Benjamin; Reininghaus, Mathias; Schwarzbauer, Jan; Püttmann, Wilhelm; Hollert, Henner; Achten, Christine



Total mercury determination in different tissues of broiler chicken by using cloud point extraction and cold vapor atomic absorption spectrometry.  


A cloud point extraction (CPE) method has been developed for the determination of total mercury (Hg) in different tissues of broiler chicken by cold vapor atomic absorption spectrometry (CVAAS). The broiler chicken tissues (leg, breast, liver and heart) were subjected to microwave assisted digestion in a mixture of nitric acid and hydrogen peroxide (2:1 ratio), prior to preconcentration by CPE. Various parameters such as the amount of ammonium O,O-diethyldithiophosphate (DDTP), concentrations of Triton X-114, equilibrium temperature, time and centrifugation have been studied in order to find the best conditions for the determination of mercury. For validation of proposed method a certified reference material, DORM-2 was used. No significant difference p>0.05 was observed between the experimental results and the certified values of CRM (paired t-test). The limit of detection and quantitation obtained under the optimal conditions were 0.117 and 0.382 microg/kg, respectively. The accumulation of Hg in different tissues were found in the order of, liver>muscles>heart. The concentration of Hg in chicken tissues were found in the range of 1.57-2.75, 1.40-2.27, 1.55-4.22, and 1.39-2.61 microg/kg in leg, breast, liver and heart, respectively. PMID:19766690

Shah, A Q; Kazi, T G; Baig, J A; Afridi, H I; Kandhro, G A; Arain, M B; Kolachi, N F; Wadhwa, S K



[Optic mixing of colours in Seurat's painting].  


Georges Seurat is the initiator and master of the divisionism. He founds the neoimpressionism current that tries to reproduce the nature exclusively through coloured vibration. Seurat applies the colours in small touches uniformly distributed on the canvas; the colours merge if they are looked by a certain distance, through optical interference. When the spectator approaches from the picture, the special frequency decreases, the optical merging does not appear and the onlooker looks a lot of coloured spots. When the spectator moves away from the picture, the optical interference appears and the clarity of the image becomes perfectly. This current opened the way of the future's modern painting performed by Cézanne, Renoir, Van Gogh. PMID:12677811

Cernea, Paul



Total phenolic contents and free radical scavenging activities of different extracts of seabuckthorn (Hippophae rhamnoides) pomace without seeds.  


In this study, 100% methanolic extract (ME), 70% aqua-methanolic extract (AME) and 100% aqueous extract of seabuckthorn byproduct were used to evaluate antioxidant activity. The total phenolic contents were high in AME (84.28 ± 1.58 mg of Gallic Acid Equivalent (GAE)/gm of extract) compared to other extracts. All the extracts scavenged different in vitro radicals in a concentration-dependent manner. The IC(50) values were lowest in AME for 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, 2,2-diphenyl-1-picrylhydrazyl, superoxide and nitric oxide radicals, while ME had lowest values for hydroxyl radicals. The reducing power of the extracts increased in a dose-dependent manner and was highest in AME. The findings of this study revealed that seabuckthorn pomace without seed is one of the important resources as an antioxidant for food, pharmaceuticals, cosmetic or nutraceutical industries. PMID:21875373

Varshneya, Chandresh; Kant, Vinay; Mehta, Madhuri



Dietary total antioxidant capacity from different assays in relation to serum C-reactive protein among young Japanese women  

PubMed Central

Background The association between dietary total antioxidant capacity (TAC) from different assays and serum C-reactive protein (CRP) has not been assessed in non-Western populations. We examined the association between dietary TAC and serum CRP concentration in young Japanese women using different four TAC assays. Methods The subjects were 443 young Japanese women aged 18–22?years. Dietary TAC was assessed with a self-administered diet history questionnaire and the TAC value of each food using the following four assays: ferric reducing ability of plasma (FRAP); oxygen radical absorbance capacity (ORAC); Trolox equivalent antioxidant capacity (TEAC); and total radical-trapping antioxidant parameter (TRAP). Serum CRP concentrations were measured by highly sensitive nephelometry. Results The major contributor to dietary TAC was green, barley, and oolong tea (FRAP: 53%, ORAC: 45%, TEAC: 36%, and TRAP: 44%). The prevalence of elevated CRP concentrations (? 1?mg/L) was 5.6%. TAC from FRAP was inversely associated with serum CRP concentrations (adjusted odds ratio [OR] for elevated CRP concentration in high [compared with low] dietary TAC group: 0.39 [95% confidence interval (CI): 0.16-0.98]; P?=?0.04). TAC from ORAC was inversely associated with CRP, although the association was not significant (OR: 0.48 [95% CI: 0.20-1.14]; P?=?0.10). TAC from TEAC was inversely associated with CRP (OR: 0.32 [95% CI: 0.12-0.82]; P?=?0.02), as was TAC from TRAP (OR: 0.31 [95% CI: 0.12-0.81]; P?=?0.02). Conclusions Dietary TAC was inversely associated with serum CRP concentration in young Japanese women regardless of assay. Further studies are needed in other populations to confirm these results.



Angle-Insensitive Structural Colours based on Metallic Nanocavities and Coloured Pixels beyond the Diffraction Limit  

PubMed Central

To move beyond colorant-based pigmentation display technologies, a variety of photonic and plasmonic crystal based structures have been designed and applied as colour filters. Nanostructure based colour filtering offers increased efficiencies, low power consumption, slim dimensions, and enhanced resolution. However, incident angle tolerance still needs to be improved. In this work, we propose a new scheme through localized resonance in metallic nanoslits by light funneling. Angle insensitive colour filters up to ±80 degrees have been achieved, capable of wide colour tunability across the entire visible band with pixel size beyond the diffraction limit (~?/2). This work opens the door to angle insensitive manipulation of light with structural filtering.

Wu, Yi-Kuei Ryan; Hollowell, Andrew E.; Zhang, Cheng; Guo, L. Jay




SciTech Connect

In these lectures, the authors develop the theory of the Colour Glass Condensate. This is the matter made of gluons in the high density environment characteristic of deep inelastic scattering or hadron-hadron collisions at very high energy. The lectures are self contained and comprehensive. They start with a phenomenological introduction, develop the theory of classical gluon fields appropriate for the Colour Glass, and end with a derivation and discussion of the renormalization group equations which determine this effective theory.




Performance evaluation of local colour invariants  

Microsoft Academic Search

In this paper, we compare local colour descriptors to grey-value descriptors. We adopt the evaluation framework of Mikolayzcyk and Schmid. We modify the framework in several ways. We decompose the evaluation framework to the level of local grey-value invariants on which common region descriptors are based. We compare the discriminative power and invariance of grey-value invariants to that of colour

Gertjan J. Burghouts; Jan-mark Geusebroek



Response of alate aphids to green targets on coloured backgrounds  

Microsoft Academic Search

To study the effect of background colour on aphid landing on green targets (water pan traps), two field experiments were set up in Hessen, Germany, in 2003. Traps were put onto coloured plastic sheets (13 colours, straw mulch, transparent foil, and uncovered soil, Experiment 1). In Experiment 2, green water pans were again put on coloured plastic sheets (red, white,

T. F. Doring; S. M. Kirchner; S. Kuhne; H. Saucke



Mechanisms, functions and ecology of colour vision in the honeybee.  


Research in the honeybee has laid the foundations for our understanding of insect colour vision. The trichromatic colour vision of honeybees shares fundamental properties with primate and human colour perception, such as colour constancy, colour opponency, segregation of colour and brightness coding. Laborious efforts to reconstruct the colour vision pathway in the honeybee have provided detailed descriptions of neural connectivity and the properties of photoreceptors and interneurons in the optic lobes of the bee brain. The modelling of colour perception advanced with the establishment of colour discrimination models that were based on experimental data, the Colour-Opponent Coding and Receptor Noise-Limited models, which are important tools for the quantitative assessment of bee colour vision and colour-guided behaviours. Major insights into the visual ecology of bees have been gained combining behavioural experiments and quantitative modelling, and asking how bee vision has influenced the evolution of flower colours and patterns. Recently research has focussed on the discrimination and categorisation of coloured patterns, colourful scenes and various other groupings of coloured stimuli, highlighting the bees' behavioural flexibility. The identification of perceptual mechanisms remains of fundamental importance for the interpretation of their learning strategies and performance in diverse experimental tasks. PMID:24828676

Hempel de Ibarra, N; Vorobyev, M; Menzel, R



Seasonal colour and antipredator behaviour in Etheostoma (Percidae).  


This study examined how colour varies across season and sex in the fantail darter Etheostoma flabellare and the banded darter Etheostoma zonale. Etheostoma flabellare has male-only parental care and exhibited slight sexual dimorphism in overall colour, with no discernible effect of season on colour; whereas E. zonale does not have parental care and exhibited substantial sexual dimorphism in colour, but only in the breeding season. Additionally, antipredator behaviour of E. zonale was compared between males that were fully coloured during the breeding season and males that were partially coloured at that time, but the effects of colour and season were not consistent across males. PMID:24588710

Moran, R L; von Ende, C N; King, B H



Two spinefoot colour morphs: mottled spinefoot Siganus fuscescens and white-spotted spinefoot Siganus canaliculatus are synonyms.  


Mottled spinefoot Siganus fuscescens and white-spotted spinefoot Siganus canaliculatus are two similar species that differ subtly in colouration and morphology. Three major mtDNA clades were identified for these species, but individuals were clustered by amplified fragment length polymorphism (AFLP) according to geography rather than morphology, suggesting that the colour morphs are interbreeding. PMID:22026611

Hsu, T-H; Adiputra, Y T; Burridge, C P; Gwo, J-C



Wine-making of High Coloured Wines: Extended Pomace Contact and Run-off of Juice Prior to Fermentation  

Microsoft Academic Search

The influence of two different oenological practices (pomace contact time and the running-off of the juice prior to fermentation) on the production of high coloured wines was analysed and tested with two vintages from the years 2001 and 2002. There were assayed three pomace contact times (15, 25 and 35 days) and 15 and 20% run-off treatments. The colour stability

A. B. Bautista-Ortín; J. I. Fernández-Fernández; J. M. López-Roca; E. Gómez-Plaza



Effects of local density and flower colour polymorphism on pollination and reproduction in the rewardless orchid Dactylorhiza sambucina (L.) Soò  

Microsoft Academic Search

The rewardless orchid Dactylorhiza sambucina shows a stable flower colour polymorphism, with both yellow- and red-flowered morphs growing sympatrically. Pollination biology and breeding system were investigated to examine the effects of density of plants, colour polymorphism, inflorescence dimension, and flower position within inflorescence on male and female reproductive success in three natural populations of D. sambucina. There were significant differences

G. Pellegrino; D. Caimi; M. E. Noce; A. Musacchio



Kinetic Model for Colour Changes in Bananas During the Appearance of Chilling Injury Symptoms  

Microsoft Academic Search

The impact of chilling injury (CI) on the colour of bananas at different ripening stages was investigated. Bananas were stored\\u000a at 6 and 13 °C for 2 days to induce CI symptoms. Images of the bananas were acquired in 1-h time intervals during the subsequent\\u000a appearance of CI at room temperature using RGB imaging system to monitor the colour changes. The raw

Norhashila Hashim; Rimfiel Bin Janius; Laszlo Baranyai; Russly Abdul Rahman; Azizah Osman; Manuela Zude


Gas Flow Measurements by 3D Particle Tracking Velocimetry Using Coloured Tracer Particles  

Microsoft Academic Search

This work describes an original approach for 3D Particle Tracking Velocimetry (3D PTV), applicable also for gaseous flows\\u000a and based on tracer particles of different colours. On the images acquired by several cameras, tracer particles are handled\\u000a by colour recognition and 3D localisation. Then, the PTV tracking algorithm rebuilds the trajectories of the tracer particles\\u000a using a criterion of Minimum Acceleration. Theoretical

Dominique Tarlet; Christian Bendicks; Christoph Roloff; Róbert Bordás; Bernd Wunderlich; Bernd Michaelis; Dominique Thévenin


Hand gesture recognition using multi-scale colour features, hierarchical models and particle filtering  

Microsoft Academic Search

This paper presents algorithms and a prototype system for hand tracking and hand posture recognition. Hand postures are represented in terms of hierarchies of multi-scale colour image features at different scales, with qualitative inter-relations in terms of scale, position and orientation. In each image, detection of multi-scale colour features is performed. Hand states are then simultaneously detected and tracked using

Lars Bretzner; Ivan Laptev; Tony Lindeberg



Hand-gesture recognition using multi-scale colour features, hierarchical features and particle filtering  

Microsoft Academic Search

This paper presents algorithms and a prototype system for hand tracking and hand posture recognition. Hand pos- tures are represented in terms of hierarchies of multi-scale colour image features at different scales, with qualitative inter-relations in terms of scale, position and orientation. In each image, detection of multi-scale colour features is per- formed. Hand states are then simultaneously detected and

Lars Bretzner; Ivan Laptev; Tony Lindeberg



Comparison of synchrotron radiation total reflection X-ray fluorescence excitation detection geometries for samples with differing matrices  

NASA Astrophysics Data System (ADS)

The linear polarization of synchrotron radiation (SR) in the orbital plane leads to a background reduction in total reflection X-ray fluorescence (TXRF) analysis if a side-looking detector is used. The optimum orientation of the sample carrier in a SR-TXRF experiment, however, is determined by a trade-off between the exploitation of the linear polarization, the efficiency of excitation and the solid angle of detection and depends on the nature and size of the sample. SR-TXRF measurements on different sample types and using different reflector orientations have been carried out at the Hamburger Synchrotronstrahlungslabor bending magnet beamline L. A NIST standard water sample, a steel sample and an oil standard were analyzed with both a horizontal and a vertical sample carrier orientation. Strongly scattering samples led to lower detection limits with a horizontal reflector whereas weakly scattering samples showed lower detection limits with a vertical reflector configuration. On an intentionally contaminated wafer absolute detection limits of 6.6 fg for Ni could be extrapolated.

Pepponi, G.; Streli, C.; Wobrauschek, P.; Zamini, S.; Zöger, N.; Falkenberg, G.



Determination of inorganic and total mercury by vapor generation atomic absorption spectrometry using different temperatures of the measurement cell  

Microsoft Academic Search

A simple and inexpensive laboratory-built flow injection vapor generation system coupled to atomic absorption spectrometry (FI-VG AAS) for inorganic and total mercury determination has been developed. It is based on the vapor generation of total mercury and a selective detection of Hg2 + or total mercury by varying the temperature of the measurement cell. Only the inorganic mercury is measured

Luiz Eduardo Kaercher; Fabiane Goldschmidt; José Neri Gottfried Paniz; Érico Marlon de Moraes Flores; Valderi Luiz Dressler



A seasnake's colour affects its susceptibility to algal fouling  

PubMed Central

Evolutionary transitions from terrestrial to aquatic life modify selective forces on an animal's coloration. For example, light penetrates differently through water than air, and a new suite of predators and visual backgrounds changes the targets of selection. We suggest that an aquatic animal's coloration may also affect its susceptibility to algal fouling. In a colour-polymorphic field population of seasnakes (Emydocephalus annulatus) in New Caledonia, black individuals supported higher algal cover than did banded conspecifics. In experimental tests, black snake models (plastic tubes) accumulated more algae than did banded models. Algal cover substantially reduced snake activity (in the field) and swimming speeds (in the laboratory). Effects of algal cover on a snake's hydrodynamic efficiency and/or its rate of cutaneous gas exchange thus may impose selection on the colours of aquatic organisms.

Shine, R.; Brischoux, F.; Pile, A. J.



Preliminary study on eye colour in Japanese macaques (Macaca fuscata) in their natural habitat.  


Eye colour in Japanese macaques shows apparent differences between individuals, continuously ranging from orange (bright), through shades of yellow and hazel-blue to dark blue (dark). We arbitrarily classified them into either 'yellow' eyes or 'blue' eyes based on the yellow area occupying in the iris' peripupillary ring. Most Japanese macaques have yellow eyes after infant phase, whilst 19, 17, 12, and 15% of monkeys (>6 months, sexes combined) have blue-eye in studied two groups of Shodoshima and two groups of Takasakiyama, respectively. Frequency of eye colour did not differ between males and females, but significantly differed in each age class. Blue eyes significantly more frequently occurred in newborns, infants and aged monkeys than in juveniles and prime adults. Data from mother-infant pairs indicated eye colour could be inherited from their parents. A case of asymmetric eye colour in Japanese macaques was found from a sample of 1962 individuals. Eye colour variation of Japanese macaques was discussed in relation to those of humans and rhesus macaques. A possible evolutionary model of eye colour in Japanese macaques was discussed. PMID:17082885

Zhang, Peng; Watanabe, Kunio



Nuclear physics in colourful worlds. Quantumchromodynamics and nuclear binding  

NASA Astrophysics Data System (ADS)

When quantumchromodynamics (QCD) is generalized from SU(3) to an SU( Nc) gauge theory, where Nc is the number of colours, it depends on only two parameters: Nc and the bare quark mass mq. A more general understanding of nuclear physics can be achieved by considering what it would be like in worlds with the number of colours different from 3, and bare quark masses different from the "empirical" ones. Such an investigation can be carried out within a framework of meson-exchange interactions. The empirical binding energy of nuclear matter results from a very near cancellation between attractive and repulsive terms which are two orders of magnitude larger and may be expected to depend sensitively on the parameters of QCD. It is indeed found that our world is wedged into a small corner of the two-dimensional manifold of mq versus Nc. If the number of colours were decreased by one, or the bare quark masses raised by more than 20%, nuclear matter would become unbound. By tracing the origin of this state of affairs, one obtains a clearer picture of the relative importance of various effects on the behaviour of the bulk nuclear matter. In particular, correlations like those embodied in the Coester band of saturation points appear to have a broader degree of validity than is implied by fits to the actual physical world only.

Müther, H.; Engelbrecht, C. A.; Brown, G. E.



GPS slant total electron content accuracy using the single layer model under different geomagnetic regions and ionospheric conditions  

NASA Astrophysics Data System (ADS)

The use of observations from the Global Positioning System (GPS) has significantly impacted the study of the ionosphere. As it is widely known, dual-frequency GPS observations can provide very precise estimation of the slant Total Electron Content (sTEC—the linear integral of the electron density along a ray-path) and that the precision level is bounded by the carrier-phase noise and multi-path effects on both frequencies. Despite its precision, GPS sTEC estimations can be systematically affected by errors in the estimation of the satellites and receivers by Inter-Frequency Biases (IFB) that are simultaneously determined with the sTEC. Thus, the ultimate accuracy of the GPS sTEC estimation is determined by the errors with which the IFBs are estimated. This contribution attempts to assess the accuracy of IFBs estimation techniques based on the single layer model for different ionospheric regions (low, mid and high magnetic latitude); different seasons (summer and winter solstices and spring and autumn equinoxes); different solar activity levels (high and low); and different geomagnetic conditions (quiet and very disturbed). The followed strategy relies upon the generation of a synthetic data set free of IFB, multi-path, measurement noise and of any other error source. Therefore, when a data set with such properties is used as the input of the IFB estimation algorithms, any deviation from zero on the estimated IFBs should be taken as indications of the errors introduced by the estimation technique. The truthfulness of this assessment work is warranted by the fact that the synthetic data sets resemble, as realistically as possible, the different conditions that may happen in the real ionosphere. The results of this work show that during the high solar activity period the accuracy for the estimated sTEC is approximately of ±10 TECu for the low geomagnetic region and of ±2.2 TECu for the mid-latitude. During low solar activity the accuracy can be assumed to be in the order of ±2 TECu. For the geomagnetic high-disturbed period, the results show that the accuracy is degraded for those stations located over the region where the storm has the strongest impact, but for those stations over regions where the storm has a moderate effect, the accuracy is comparable to that obtained in the quiet period.

Brunini, C.; Azpilicueta, F.



Oxygenated-Blood Colour Change Thresholds for Perceived Facial Redness, Health, and Attractiveness  

PubMed Central

Blood oxygenation level is associated with cardiovascular fitness, and raising oxygenated blood colouration in human faces increases perceived health. The current study used a two-alternative forced choice (2AFC) psychophysics design to quantify the oxygenated blood colour (redness) change threshold required to affect perception of facial colour, health and attractiveness. Detection thresholds for colour judgments were lower than those for health and attractiveness, which did not differ. The results suggest redness preferences do not reflect a sensory bias, rather preferences may be based on accurate indications of health status. Furthermore, results suggest perceived health and attractiveness may be perceptually equivalent when they are assessed based on facial redness. Appearance-based motivation for lifestyle change can be effective; thus future studies could assess the degree to which cardiovascular fitness increases face redness and could quantify changes in aerobic exercise needed to increase facial attractiveness.

Re, Daniel E.; Whitehead, Ross D.; Xiao, Dengke; Perrett, David I.



Colour constancy from temporal cues: better matches with less variability under fast illuminant changes.  


To test whether temporal transient cues could improve colour-constancy estimates, surface-colour matches were made across two Mondrian patterns illuminated by different daylights: the patterns were presented either in the same position in an alternating sequence or, as a control, simultaneously side-by-side. The degree of colour constancy was significantly higher with sequential stimulus presentation than with simultaneous presentation, in the best condition reaching 0.87 on a scale of 0 to 1 for matches averaged over 20 observers. The variance between observers was also markedly reduced with sequential stimulus presentation. The visual system appears to have mechanisms not requiring adaptation that can provide almost unbiased information about surface colour under changing illuminants. PMID:11164445

Foster, D H; Amano, K; Nascimento, S M



Colour within an internalist framework: The role of 'colour' in the structure of the perceptual system  

Microsoft Academic Search

Colour is, according to prevailing orthodoxy in perceptual psychology, a kind of autonomous and unitary attribute. It is regarded as unitary or homogeneous by assuming that its core properties do not depend on the type of 'perceptual object' to which it pertains and that 'colour per se' constitutes a natural attribute in the functional architecture of the perceptual system. It

Rainer Mausfeld


Memory colours and colour quality evaluation of conventional and solid-state lamps.  


A colour quality metric based on memory colours is presented. The basic idea is simple. The colour quality of a test source is evaluated as the degree of similarity between the colour appearance of a set of familiar objects and their memory colours. The closer the match, the better the colour quality. This similarity was quantified using a set of similarity distributions obtained by Smet et al. in a previous study. The metric was validated by calculating the Pearson and Spearman correlation coefficients between the metric predictions and the visual appreciation results obtained in a validation experiment conducted by the authors as well those obtained in two independent studies. The metric was found to correlate well with the visual appreciation of the lighting quality of the sources used in the three experiments. Its performance was also compared with that of the CIE colour rendering index and the NIST colour quality scale. For all three experiments, the metric was found to be significantly better at predicting the correct visual rank order of the light sources (p < 0.1). PMID:21164972

Smet, Kevin A G; Ryckaert, Wouter R; Pointer, Michael R; Deconinck, Geert; Hanselaer, Peter



Shear bond strength of self-etch and total-etch bonding systems at different dentin depths.  


The purpose of this study was to evaluate the dentin shear bond strength of four adhesive systems (Adper Single Bond 2, Adper Prompt L-Pop, Magic Bond DE and Self Etch Bond) in regards to buccal and lingual surfaces and dentin depth. Forty extracted third molars had roots removed and crowns bisected in the mesiodistal direction. The buccal and lingual surfaces were fixed in a PVC/acrylic resin ring and were divided into buccal and lingual groups assigned to each selected adhesive. The same specimens prepared for the evaluation of superficial dentin shear resistance were used to evaluate the different depths of dentin. The specimens were identified and abraded at depths of 0.5, 1.0, 1.5 and 2.0 mm. Each depth was evaluated by ISO TR 11405 using an EMIC-2000 machine regulated at 0.5 mm/min with a 200 Kgf load cell. We performed statistical analyses on the results (ANOVA, Tukey and Scheffé tests). Data revealed statistical differences (p < 0.01) in the adhesive and depth variation as well as adhesive/depth interactions. The Adper Single Bond 2 demonstrated the highest mean values of shear bond strength. The Prompt L-Pop product, a self-etching adhesive, revealed higher mean values compared with Magic Bond DE and Self Etch Bond adhesives, a total and self-etching adhesive respectively. It may be concluded that the shear bond strength of dentin is dependent on material (adhesive system), substrate depth and adhesive/depth interaction. PMID:21359489

Villela-Rosa, Ana Carolina Maito; Gonçalves, Mariane; Orsi, Iara Augusta; Miani, Paola Kirsten



Removal of Brown Colour From Diamonds During Storage in the Lithospheric Mantle  

NASA Astrophysics Data System (ADS)

Brown colour in natural diamonds is produced by plastic deformation during residence in the mantle. Dislocation movement generates vacancies, which aggregate into clusters of about 30-60 vacancies. The resulting electronic configuration at each cluster leads to the broad, featureless absorption pattern associated with common brown colour. Less commonly, other brownish colours can be attributed to hydrogen or isolated nitrogen atoms, H4 centres, or possibly oxygen. The common brown colour can be removed by high-pressure-high-temperature (HPHT) treatment. This process involves pressures and temperatures of 5-9 GPa and 1800-2700 ° C, respectively. Treatment may take several minutes or hours. It has been suggested that brown diamonds stored in the lithospheric mantle should lose their colour by analogy to HPHT treatment. If so, brown colour must be the product of late deformation (close to kimberlite eruption) or the brown diamonds must be stored above the diamond stability field (in a cooler part of the lithosphere). Is it reasonable to expect brown colour to be destroyed in the lithospheric mantle? An objective analysis of this question must consider temperature. Higher temperatures result in faster colour removal. HPHT treatment occurs at 1800-2700 ° C, whereas inclusion thermometry places most lithospheric diamonds in the range of 900-1400 ° C. Destruction of the brown colour centre involves breaking up vacancy clusters. The activation energy required to do this can be estimated as the energy of an isolated monovacancy, minus the energy per vacancy of the cluster, plus the vacancy migration energy. Data from recent literature produces a value of 7.7 eV. The Arrhenius equation can be modified to show how reaction time varies with temperature. The activation energy can be used in conjunction with experimental HPHT data to extrapolate reaction times from HPHT temperatures to lithospheric mantle temperatures. For a certain reduction in brown colour produced by HPHT (T1, t1), the equation below shows the time required (t2) to produce the same reduction at a different temperature (T2): ln(t2) = ln(t1) + (Ea/k)(1/T2 - 1/T1) where Ea is activation energy, k is the Boltzmann constant, and temperatures are in kelvin. A relatively potent treatment of 1 hour at 2500 ° C is comparable to about 109 years at 1150 ° C. Most diamonds would lose any brown colour in this scenario. Modest colour reduction is detectable after 5 hours at 1800 ° C. This is comparable to about 109 years at 950 ° C, or about 105 years at 1150 ° C. The time required to destroy brown colour in the lithospheric mantle is significant at the scale of geological time. Brown diamonds should easily maintain their colour during cooler mantle storage at or below 1000 ° C. Warmer temperatures toward the base of the lithosphere may be able to reduce or eliminate brown colour within a reasonable geological time frame. The survival of brown colour in the lithospheric mantle does not require the colour to be formed late in the storage history nor does it require metastable storage in the graphite stability field.

Smith, E. M.; Helmstaedt, H. H.



Determination of inorganic and total mercury by vapor generation atomic absorption spectrometry using different temperatures of the measurement cell  

Microsoft Academic Search

A simple and inexpensive laboratory-built flow injection vapor generation system coupled to atomic absorption spectrometry (FI-VG AAS) for inorganic and total mercury determination has been developed. It is based on the vapor generation of total mercury and a selective detection of Hg2+ or total mercury by varying the temperature of the measurement cell. Only the inorganic mercury is measured when

Luiz Eduardo Kaercher; Fabiane Goldschmidt; José Neri Gottfried Paniz; Érico Marlon de Moraes Flores; Valderi Luiz Dressler



Influence of natural weathering on colour stability of materials used for facial prosthesis.  


Colour stability of resin and silicone is an important factor for longevity of facial prostheses. The aim of this study was to evaluate the colour stability of resins and silicone for facial prostheses. Three brands of acrylic resin and one of facial silicone were evaluated considering pigment incorporation for the colourless materials. Ten samples of each material were fabricated and submitted to measurements of chromatic alteration initially and after 90 and 180 days of weathering natural through visual analysis and spectrophotometry. Data were evaluated by ANOVA and Tukey test (p < 0.05). Statistically significant colour alteration was observed among some materials regardless of the period. The materials did not present a statistical difference between 90 and 180 days except for the pigmented heat-polymerized resin. The colour difference between pigmented Silastic MDX4-4210 and colourless Silastic was statistically significant (p < 0.01) in both periods as well as between pigmented and colourless heat-polymerized resin, and between the resins Rapidaflex and Lentaflex. The visual method demonstrated colour alteration in all materials evaluated during the first 90 days of ageing. All materials exhibited colour alteration due to exposure to environment. PMID:22716457

dos Santos, D M; Goiato, M C; Sinhoreti, M A C; Moreno, A; Dekon, S F C; Haddad, M F; Pesqueira, A A



Genotypic variation in yellow autumn leaf colours explains aphid load in silver birch.  


• It has been suggested that autumn-migrating insects drive the evolution of autumn leaf colours. However, evidence of genetic variation in autumn leaf colours in natural tree populations and the link between the genetic variation and herbivore abundances has been lacking. • Here, we measured the size of the whole aphid community and the development of green-yellow leaf colours in six replicate trees of 19 silver birch (Betula pendula) genotypes at the beginning, in the middle and at the end of autumn colouration. We also calculated the difference between green leaf and leaf litter nitrogen (N) and estimated the changes in phloem sap N loading. • Autumn leaf colouration had significant genetic variation. During the last survey, genotypes that expressed the strongest leaf reflectance 2-4 wk earlier had an abundance of egg-laying Euceraphis betulae females. Surprisingly, the aphid community size during the first surveys explained N loss by the litter of different birch genotypes. • Our results are the first evidence at the tree intrapopulation genotypic level that autumn-migrating pests have the potential to drive the evolution of autumn leaf colours. They also stress the importance of recognizing the role of late-season tree-insect interactions in the evolution of herbivory resistance. PMID:22548444

Sinkkonen, Aki; Somerkoski, Eeva; Paaso, Ulla; Holopainen, Jarmo K; Rousi, Matti; Mikola, Juha



Observation of even-parity autoionization states of uranium by three-colour photoionization optogalvanic spectroscopy in U-Ne hollow cathode discharges  

NASA Astrophysics Data System (ADS)

Three-colour three-step photoionization spectroscopy of uranium has been performed in a U-Ne hollow cathode discharge tube by temporally resolving three-colour photoionization optogalvanic (PIOG) signal from the normal optogalvanic (OG) signal using three tunable pulsed dye lasers. U-Ne hollow cathode discharge tube has been used as a source of uranium atomic vapours and photoionization detector. Using this technique, photoionization spectra of uranium have been investigated systematically in the energy region 52,150-52,590cm-1, through three different excitation pathways, originating from its ground state, 0cm-1(5Lo6). By analysing the three-colour photoionization spectra sixty new even-parity autoionization resonances of uranium have been identified and their probable total angular momentum (J) values have been assigned according to the J-momentum selection rule. The J-value of five autoionization resonances, which have been observed either through all three excitation pathways or through two different excitation pathways where J-value of the second excited levels differs by two, has been assigned uniquely.

Mandal, P. K.; Seema, A. U.; Das, R. C.; Shah, M. L.; Dev, Vas; Suri, B. M.



Colour unmasks dark targets in complex displays.  


Recent studies have suggested that colour (meaning chromatic) variations help the visual system segment luminance-variegated displays into their illumination and reflectance layers. This leads to the prediction that colour variations should unmask partially camouflaged achromatic transparencies on luminance-variegated backgrounds. We used 'Mondrian-like' backgrounds that were either achromatic, i.e., varying only in luminance, or chromatic, which in our stimuli meant varying in both luminance and colour. Both achromatic and chromatic backgrounds had the same luminance distribution. Thresholds for detecting simulated transparency targets were found to be lower when on the chromatic compared to achromatic backgrounds. We hypothesised that the chromatic-background advantage resulted from the extra cue provided by colour as to which borders were background and which transparency, predicting that (a) randomising the colours on either side of the transparency border, (b) rotating the target to destroy its X-junctions, and (c) viewing the target eccentrically, would each destroy the chromatic-background advantage. However, none of these predictions was upheld. We suggest therefore that the chromatic-background advantage is due to a low-level, rather than border-disambiguation mechanism. We suggest that chromatic variations reduce the noise, but not the signal, in the mechanism that detects dark targets in complex displays. PMID:16226784

Kingdom, Frederick A A; Kasrai, Reza



Multispectral image invariant to illumination colour, strength, and shading  

NASA Astrophysics Data System (ADS)

We present here a method that makes use of multispectral image data and generates a novel "photometric-invariant multispectral image" for this type of data. For RGB, an invariant image has been constructed independent of the colour and intensity of the illuminant and of shading. To generate this image either a set of calibration images is required, or entropy information taken from a single image can be used to develop the parameters necessary to produce the invariant. Nonetheless, generating an invariant image remains a complex and error-prone task for RGB image data. For multispectral images, we show that photometric-invariant image formation is in essence greatly simplified. One of the requirements for forming an invariant is the necessity of narrowband-sensor sensors. Here this is the case, and we show that with the simple knowledge of peak sensor wavelengths we can generate a high-D multispectral invariant. The PSNR is shown to be high between the respective invariant multispectral features for multispectral images taken under different illumination conditions, showing lighting invariance for a per-pixel measure; and the s-CIELAB error measure shows that the colour error between the 3-D colour images used to visualize the output invariant high-D data is also small.

Drew, Mark S.; Yazdani Salekdeh, Amin



Environment-contingent sexual selection in a colour polymorphic fish  

PubMed Central

Sexual selection could be a driving force in the maintenance of intraspecific variation, but supporting observations from nature are limited. Here, we test the hypothesis that spatial heterogeneity of the visual environment can influence sexual selection on colourful male secondary traits such that selective advantage is environment contingent. Using a small fish endemic to Sulawesi, Indonesia (Telmatherina sarasinorum) that has five male colour morphs varying in frequency between two visually distinct mating habitats, we used direct behavioural observations to test the environment-contingent selection hypothesis. These observations were combined with measurements of the visual environment, fish coloration and the sensitivity of visual photopigments to determine whether differential morph conspicuousness was associated with reproductive success across habitats. We found that blue and yellow males are most conspicuous in different habitats, where they also have the highest reproductive fitness. A less conspicuous grey morph also gained high reproductive success in both habitats, raising the possibility that alternative behaviours may also contribute to reproductive success. In a comprehensive analysis, conspicuousness was strongly correlated with reproductive success across morphs and environments. Our results suggest an important role for spatially heterogeneous environments in the maintenance of male colour polymorphism.

Gray, Suzanne M; Dill, Lawrence M; Tantu, Fadly Y; Loew, Ellis R; Herder, Fabian; McKinnon, Jeffrey S



Geometric and Colour Data Fusion for Outdoor 3D Models  

PubMed Central

This paper deals with the generation of accurate, dense and coloured 3D models of outdoor scenarios from scanners. This is a challenging research field in which several problems still remain unsolved. In particular, the process of 3D model creation in outdoor scenes may be inefficient if the scene is digitalized under unsuitable technical (specific scanner on-board camera) and environmental (rain, dampness, changing illumination) conditions. We address our research towards the integration of images and range data to produce photorealistic models. Our proposal is based on decoupling the colour integration and geometry reconstruction stages, making them independent and controlled processes. This issue is approached from two different viewpoints. On the one hand, given a complete model (geometry plus texture), we propose a method to modify the original texture provided by the scanner on-board camera with the colour information extracted from external images taken at given moments and under specific environmental conditions. On the other hand, we propose an algorithm to directly assign external images onto the complete geometric model, thus avoiding tedious on-line calibration processes. We present the work conducted on two large Roman archaeological sites dating from the first century A.D., namely, the Theatre of Segobriga and the Fori Porticus of Emerita Augusta, both in Spain. The results obtained demonstrate that our approach could be useful in the digitalization and 3D modelling fields.

Merchan, Pilar; Adan, Antonio; Salamanca, Santiago; Dominguez, Vicente; Chacon, Ricardo



Estimates of genetic parameters for total milk yield over multiple ages in Brazilian Murrah buffaloes using different models.  


The objective of this study was to estimate variance components and genetic parameters for accumulated 305-day milk yield (MY305) over multiple ages, from 24 to 120 months of age, applying random regression (RRM), repeatability (REP) and multi-trait (MT) models. A total of 4472 lactation records from 1882 buffaloes of the Murrah breed were utilized. The contemporary group (herd-year-calving season) and number of milkings (two levels) were considered as fixed effects in all models. For REP and RRM, additive genetic, permanent environmental and residual effects were included as random effects. MT considered the same random effects as did REP and RRM with the exception of permanent environmental effect. Residual variances were modeled by a step function with 1, 4, and 6 classes. The heritabilities estimated with RRM increased with age, ranging from 0.19 to 0.34, and were slightly higher than that obtained with the REP model. For the MT model, heritability estimates ranged from 0.20 (37 months of age) to 0.32 (94 months of age). The genetic correlation estimates for MY305 obtained by RRM (L23.res4) and MT models were very similar, and varied from 0.77 to 0.99 and from 0.77 to 0.99, respectively. The rank correlation between breeding values for MY305 at different ages predicted by REP, MT, and RRM were high. It seems that a linear and quadratic Legendre polynomial to model the additive genetic and animal permanent environmental effects, respectively, may be sufficient to explain more parsimoniously the changes in MY305 genetic variation with age. PMID:24782092

Sesana, R C; Baldi, F; Borquis, R R A; Bignardi, A B; Hurtado-Lugo, N A; El Faro, L; Albuquerque, L G; Tonhati, H



Variability in Avian Eggshell Colour: A Comparative Study of Museum Eggshells  

PubMed Central

Background The exceptional diversity of coloration found in avian eggshells has long fascinated biologists and inspired a broad range of adaptive hypotheses to explain its evolution. Three main impediments to understanding the variability of eggshell appearance are: (1) the reliable quantification of the variation in eggshell colours; (2) its perception by birds themselves, and (3) its relation to avian phylogeny. Here we use an extensive museum collection to address these problems directly, and to test how diversity in eggshell coloration is distributed among different phylogenetic levels of the class Aves. Methodology and Results Spectrophotometric data on eggshell coloration were collected from a taxonomically representative sample of 251 bird species to determine the change in reflectance across different wavelengths and the taxonomic level where the variation resides. As many hypotheses for the evolution of eggshell coloration assume that egg colours provide a communication signal for an avian receiver, we also modelled reflectance spectra of shell coloration for the avian visual system. We found that a majority of species have eggs with similar background colour (long wavelengths) but that striking differences are just as likely to occur between congeners as between members of different families. The region of greatest variability in eggshell colour among closely related species coincided with the medium-wavelength sensitive region around 500 nm. Conclusions The majority of bird species share similar background eggshell colours, while the greatest variability among species aligns with differences along a red-brown to blue axis that most likely corresponds with variation in the presence and concentration of two tetrapyrrole pigments responsible for eggshell coloration. Additionally, our results confirm previous findings of temporal changes in museum collections, and this will be of particular concern for studies testing intraspecific hypotheses relating temporal patterns to adaptation of eggshell colour. We suggest that future studies investigating the phylogenetic association between the composition and concentration of eggshell pigments, and between the evolutionary drivers and functional impacts of eggshell colour variability will be most rewarding.

Cassey, Phillip; Portugal, Steven J.; Maurer, Golo; Ewen, John G.; Boulton, Rebecca L.; Hauber, Mark E.; Blackburn, Tim M.



The Impact of Biochemistry vs. Population Membership on Floral Scent Profiles in Colour Polymorphic Hesperis matronalis  

PubMed Central

Background and Aims Studies of floral scent evolution often attribute variation in floral scent to differences in pollinator behaviour, ignoring the potential for shared biochemistry between floral scent and floral colour to dictate patterns of phenotypic variation in scent production. To determine the relative effects of shared biochemistry and/or localized population-level phenomena on floral scent phenotype, floral scent composition and emission rate were examined in five wild populations of colour polymorphic Hesperis matronalis (Brassicaceae). Methods Floral scent was collected by in situ dynamic headspace extraction on purple and white colour morphs in each of five wild populations. Gas chromatography–mass spectroscopy of extracts allowed determination of floral scent composition and emission rate for all individuals, which were examined by non-metric multidimensional scaling and analysis of variance (ANOVA), respectively, to determine the contributions of floral colour and population membership to scent profile variation. Key Results Despite the fact that colour morph means were very similar in some populations and quite different in other populations, colour morphs within populations did not differ from each other in terms of scent composition or emission rate. Populations differed significantly from one another in terms of both floral scent composition and emission rate. Conclusions Shared biochemistry alone cannot explain the variation in floral scent phenotype found for H. matronalis. Such a result may suggest that the biochemical association between floral scent and floral colour is complex or dependent on genetic background. Floral scent does vary significantly with population membership; several factors, including environmental conditions, founder effects and genetics, may account for this differentiation and should be considered in future studies.

Majetic, Cassie J.; Raguso, Robert A.; Ashman, Tia-Lynn



Relative contributions of soil, foliar, and woody tissue respiration to total ecosystem respiration in four pine forests of different ages  

NASA Astrophysics Data System (ADS)

Carbon dioxide (CO2) emissions from soil, foliage, and live woody tissue were measured throughout the year in afforested, white pine (Pinus strobus L.) stands (67, 32, 17, and 4 years old as of 2006), growing in a northern temperate climate. The data were used to estimate annual ecosystem respiration (Re) and its component fluxes, including soil, foliar, and woody tissue respiration; to investigate major environmental factors causing intersite and temporal variability in the observed fluxes; and to compare chamber-based Re estimates with eddy covariance-based estimates. While temperature was the dominant driving factor of temporal variability in component fluxes, intersite variability in CO2 emissions was attributed to differences in stand physiological characteristics, such as the presence of the LFH soil horizon, its carbon-to-nitrogen ratio, and the amount of canopy cover. Additional factors that contributed to flux variability included the frequency of precipitation events, vapor pressure deficit and stem diameter, depending on the component considered. Estimated annual chamber-based totals of Re across the four stands were 1526 ± 137, 1278 ± 137, 1985 ± 293, and 773 ± 46 g C m-2 yr-1 for the 67-, 32-, 17-, and 4-year-old stands, respectively. Soil respiration dominated emissions at the 4-year-old stand, while foliar respiration dominated emissions at the 17-year-old stand. In contrast, at the two oldest stands, soil and foliar respirations were comparable. Soil respiration accounted for 44%, 44%, 26%, and 70% of annual Re, across the 67-, 32-, 17-, and 4-year-old stands, while foliar respiration accounted for 48%, 41%, 60%, and 30% of annual Re, across the respective sites. Wood respiration was the smallest component of annual Re across the stands (8%, 15%, 14%, and 0.1%, respectively). The chamber-based Re values were higher than tower-based eddy covariance Re estimates, on average by 18%, 70%, 18%, and 36% at the 67-, 32-, 17-, and 4-year-old stands, respectively. This study contributes to our general understanding of the age-related effects and the role of climate on carbon emissions from various components of afforested ecosystems. Our results suggest that foliar respiration could be comparable to or higher than soil respiration in its contribution to Re in young to mature, planted or afforested, ecosystems. They also suggest that site quality and stand age are important factors to be considered in future studies of carbon dynamics of afforested stands.

Khomik, Myroslava; Arain, M. Altaf; Brodeur, Jason J.; Peichl, Matthias; Restrepo-Coupé, Natalia; McLaren, Joshua D.



Transcriptome sequencing and metabolite analysis reveals the role of delphinidin metabolism in flower colour in grape hyacinth  

PubMed Central

Grape hyacinth (Muscari) is an important ornamental bulbous plant with an extraordinary blue colour. Muscari armeniacum, whose flowers can be naturally white, provides an opportunity to unravel the complex metabolic networks underlying certain biochemical traits, especially colour. A blue flower cDNA library of M. armeniacum and a white flower library of M. armeniacum f. album were used for transcriptome sequencing. A total of 89 926 uni-transcripts were isolated, 143 of which could be identified as putative homologues of colour-related genes in other species. Based on a comprehensive analysis relating colour compounds to gene expression profiles, the mechanism of colour biosynthesis was studied in M. armeniacum. Furthermore, a new hypothesis explaining the lack of colour phenotype of the grape hyacinth flower is proposed. Alteration of the substrate competition between flavonol synthase (FLS) and dihydroflavonol 4-reductase (DFR) may lead to elimination of blue pigmentation while the multishunt from the limited flux in the cyanidin (Cy) synthesis pathway seems to be the most likely reason for the colour change in the white flowers of M. armeniacum. Moreover, mass sequence data obtained by the deep sequencing of M. armeniacum and its white variant provided a platform for future function and molecular biological research on M. armeniacum.

Lou, Qian; Liu, Yali; Qi, Yinyan; Jiao, Shuzhen; Tian, Feifei; Jiang, Ling; Wang, Yuejin



Transcriptome sequencing and metabolite analysis reveals the role of delphinidin metabolism in flower colour in grape hyacinth.  


Grape hyacinth (Muscari) is an important ornamental bulbous plant with an extraordinary blue colour. Muscari armeniacum, whose flowers can be naturally white, provides an opportunity to unravel the complex metabolic networks underlying certain biochemical traits, especially colour. A blue flower cDNA library of M. armeniacum and a white flower library of M. armeniacum f. album were used for transcriptome sequencing. A total of 89 926 uni-transcripts were isolated, 143 of which could be identified as putative homologues of colour-related genes in other species. Based on a comprehensive analysis relating colour compounds to gene expression profiles, the mechanism of colour biosynthesis was studied in M. armeniacum. Furthermore, a new hypothesis explaining the lack of colour phenotype of the grape hyacinth flower is proposed. Alteration of the substrate competition between flavonol synthase (FLS) and dihydroflavonol 4-reductase (DFR) may lead to elimination of blue pigmentation while the multishunt from the limited flux in the cyanidin (Cy) synthesis pathway seems to be the most likely reason for the colour change in the white flowers of M. armeniacum. Moreover, mass sequence data obtained by the deep sequencing of M. armeniacum and its white variant provided a platform for future function and molecular biological research on M. armeniacum. PMID:24790110

Lou, Qian; Liu, Yali; Qi, Yinyan; Jiao, Shuzhen; Tian, Feifei; Jiang, Ling; Wang, Yuejin



Metal nanoparticle-doped coloured films on glass and polycarbonate substrates  

NASA Astrophysics Data System (ADS)

In a program on the development of metal (e.g. Au, Ag, Cu and their alloy) nanoparticles in sol-gel derived films, attempts were made to synthesize different coloured coatings on glasses and plastics. The absorption position of surface plasmon resonance (SPR) band arising from the embedded metal nanoparticles was tailored by controlling the refractive index of the matrix for the development of different colours. Thus different coloured (pink to blue) coatings on ordinary sheet glasses were prepared by generating Au nanoparticles in mixed SiO_{2}-TiO_{2} matrices having refractive index values ranging from about 1.41 to 1.93. In another development, textit{in situ} generation of Ag nanoparticles in the inorganic-organic hybrid host leads to the formation of different abrasion resistant coloured coatings (yellow to pink) on polycarbonate substrates after curing. As expected, the SPR peak of Ag or Au is gradually red-shifted due to the increase of refractive index of the coating matrices causing a systematic change of colour.

Medda, S. K.; Mitra, M.; de, S.; Pal, S.; de, G.



Floral colour versus phylogeny in structuring subalpine flowering communities  

PubMed Central

The relative number of seeds produced by competing species can influence the community structure; yet, traits that influence seed production, such as pollinator attraction and floral colour, have received little attention in community ecology. Here, we analyse floral colour using reflectance spectra that include near-UV and examined the phylogenetic signal of floral colour. We found that coflowering species within communities tended to be more divergent in floral colour than expected by chance. However, coflowering species were not phylogenetically dispersed, in part due to our finding that floral colour is a labile trait with a weak phylogenetic signal. Furthermore, while we found that locally rare and common species exhibited equivalent floral colour distances from their coflowering neighbours, frequent species (those found in more communities) exhibited higher colour distances from their coflowering neighbours. Our findings support recent studies, which have found that (i) plant lineages exhibit frequent floral colour transitions; and (ii) traits that influence local population dynamics contribute to community structure.

McEwen, Jamie R.; Vamosi, Jana C.



Quantum entanglement of quark colour states  

SciTech Connect

An analysis of quantum entanglement between the states of static colour charges in the vacuum of pure Yang-Mills theory is carried out. Hilbert space of physical states of the fields and the charges is endowed with a direct product structure by attaching an infinite Dirac string to each charge.

Buividovich, P. V. [JIPNR, National Academy of Science, 220109 Belarus, Minsk, Acad. Krasin str. 99 (Belarus); ITEP, 117218 Russia, Moscow, B. Cheremushkinskaya str. 25 (Russian Federation); Kuvshinov, V. I. [JIPNR, National Academy of Science, 220109 Belarus, Minsk, Acad. Krasin str. 99 (Belarus)



Fast Synthesis of Dynamic Colour Textures  

Microsoft Academic Search

Textural appearance of many real word materials is not static but shows progress in time. If such a progress is spa- tially and temporally homogeneous these materials can be represented by means of dynamic texture (DT). DT mod- elling is a challenging problem which can add new quality into computer graphics applications. We propose a novel hybrid method for colour

Jirí Filip; Michal Haindl; Dmitry Chetverikov



Genetics of human iris colour and patterns.  


The presence of melanin pigment within the iris is responsible for the visual impression of human eye colouration with complex patterns also evident in this tissue, including Fuchs' crypts, nevi, Wolfflin nodules and contraction furrows. The genetic basis underlying the determination and inheritance of these traits has been the subject of debate and research from the very beginning of quantitative trait studies in humans. Although segregation of blue-brown eye colour has been described using a simple Mendelian dominant-recessive gene model this is too simplistic, and a new molecular genetic perspective is needed to fully understand the biological complexities of this process as a polygenic trait. Nevertheless, it has been estimated that 74% of the variance in human eye colour can be explained by one interval on chromosome 15 that contains the OCA2 gene. Fine mapping of this region has identified a single base change rs12913832 T/C within intron 86 of the upstream HERC2 locus that explains almost all of this association with blue-brown eye colour. A model is presented whereby this SNP, serving as a target site for the SWI/SNF family member HLTF, acts as part of a highly evolutionary conserved regulatory element required for OCA2 gene activation through chromatin remodelling. Major candidate genes possibly effecting iris patterns are also discussed, including MITF and PAX6. PMID:19619260

Sturm, Richard A; Larsson, Mats



Colour Interest Points for Image Retrieval  

Microsoft Academic Search

In image retrieval scenarios, many methods use interest point detection at an early stage to find regions in which descriptors are calculated. Finding salient locations in image data is crucial for these tasks. Observing that most current methods use only the luminance information of the images, we investigate the use of colour information in in- terest point detection. Based on

Nicu Sebe; Theo Gevers; Allan Hanbury



Colour-dependent target detection by bees  

Microsoft Academic Search

The distance over which an object is detected by bees depends on the subtended visual angle and on spectral cues. At large angular subtenses detection is mediated only by chromatic cues. Achromatic targets, however, are also detectable. We investigated how chromatic and achromatic cues interact in detecting large-size targets. Coloured targets were used, with varied chromatic contrast that either did

C. Niggebrügge; N. Hempel de Ibarra



The Coloured Product of the Sakaguchi Reaction  

Microsoft Academic Search

WE have already reported1 that the coloured product of the Sakaguchi reaction2 (between arginine and alpha-naphthol) behaves as a typical acid-base indicator, being red in alkali and yellow3 in acid. It has now been found that the compound behaves as an oxidation-reduction indicator also.

Kshirod R. Bhattacharya



Demonstration of the Colour Range of Indicators  

ERIC Educational Resources Information Center

Describes the construction of a box that is filled with indicator of a particular concentration. A little acid is added to one side and a little alkali to the other so that the complete colour range of the indicator is observable. (GS)

Woods, G. T.



Serum lipids and total fatty acids in chronic alcoholic liver disease at different stages of cell damage  

Microsoft Academic Search

Summary Lipid classes and per cent composition of total fatty acids were investigated in serum of normal subjects and patients with chronic alcoholic liver disease. In view of the histological findings, the latter were classified in 5 groups according to the severity of their liver damage.

A. Marzo; P. Ghirardi; D. Sardini; B. D. Prandini; A. Albertini




EPA Science Inventory

Deposit-feeding marine clams (Macoma nasuta) were exposed for 119d to three sediment types that varied in total organic carbon (TOC) from 0.8 to 2.5%. ediments were spiked with equal concentrations of 13 polychlorinated biphenyl congeners and hexachlorobenzene. issue residues wer...


Detection of coloured stimuli by honeybees: minimum visual angles and receptor specific contrasts  

Microsoft Academic Search

Honeybees Apis mellifera were trained to distinguish between the presence and the absence of a rewarded coloured spot, presented on a vertical, achromatic plane in a Y-maze. They were subsequently tested with different subtended visual angles of that spot, generated by different disk diameters and different distances from the decision point in the device. Bees were trained easily to detect

M. Giurfa; M. Vorobyev; P. Kevan; R. Menzel



Sputum colour for diagnosis of a bacterial infection in patients with acute cough  

PubMed Central

Objective Sputum colour plays an important role in the disease concepts for acute cough, both in the patients’ and the doctors’ view. However, it is unclear whether the sputum colour can be used for diagnosis of a bacterial infection. Design Cross-sectional study. Setting A total of 42 GP practices in Düsseldorf, Germany. Subjects Sputum samples obtained from 241 patients suffering from an episode of acute cough seeing their doctor within a routine consultation. Main outcome measures Relation of sputum colour and microbiological proof of bacterial infection defined as positive culture and at least a moderate number of leucocytes per low magnification field. Results In 28 samples (12%) a bacterial infection was proven. Yellowish or greenish colour of the sputum sample and bacterial infection showed a significant correlation (p = 0.014, Fisher's exact test). The sensitivity of yellowish or greenish sputum used as a test for a bacterial infection was 0.79 (95% CI 0.63–0.94); the specificity was 0.46 (95% CI 0.038–0.53). The positive likelihood-ratio (+LR) was 1.46 (95% CI 1.17-1.85). Conclusions The sputum colour of patients with acute cough and no underlying chronic lung disease does not imply therapeutic consequences such as prescription of antibiotics.

Altiner, Attila; Wilm, Stefan; Daubener, Walter; Bormann, Christiane; Pentzek, Michael; Abholz, Heinz-Harald; Scherer, Martin



Female-specific colouration, carotenoids and reproductive investment in a dichromatic species, the upland goose Chloephaga picta leucoptera.  


Although studies on the evolution and function of female ornaments have become more numerous in the last years, the majority of these studies were carried out in cases where female ornaments were a smaller and duller version of the ornaments found in males. There are substantially fewer studies on species with female-specific ornaments. However, no study so far investigated the potential of female-specific colouration as a quality signal in birds with conventional sex roles. We studied female-specific ornamentation in a strongly sexually dichromatic species, the upland goose Chloephaga picta leucoptera, in two consecutive years. Male upland geese have white head and breast feathers and black legs, whereas females have reddish-brown head and breast feathers and conspicuous yellow-orange legs. We found that female-specific colouration in upland geese can reliably indicate different aspects of female phenotypic quality. Females with more orange coloured legs and more red-like head colours had higher clutch and egg volumes than females with a paler leg and head colouration, and a more reddish plumage colouration was related to a higher body condition. These relationships provide the theoretic possibility for males to assess female phenotypic quality on the basis of colouration. Furthermore, the females with a more orange-like tarsus colouration had higher plasma carotenoid levels. Both tarsus colouration and carotenoid concentrations of individual females were highly correlated across years, indicating that tarsus colour is a stable signal. Despite this correlation, small individual differences in plasma carotenoid concentrations between the two study years were related to differences in tarsus colouration. We thus show for the first time in a wild bird and under natural conditions that carotenoid-based integument colouration remains consistent between individuals in consecutive years and is also a dynamic trait reflecting individual changes in carotenoid levels. In this species, where pairs form life-long bonds, the honesty of the carotenoid-based integument colouration suggests that it may be a sexually selected female ornament that has evolved through male mate choice. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00265-010-0990-4) contains supplementary material, which is available to authorized users. PMID:20976290

Gladbach, Anja; Gladbach, David Joachim; Kempenaers, Bart; Quillfeldt, Petra



Distribution of colour-selective activity in the monkey inferior temporal cortex revealed by functional magnetic resonance imaging.  


Previous electrophysiological, neuroimaging and lesion studies have suggested that the anterior part of the monkey inferior temporal (IT) cortex, or area TE, plays an important role in colour processing. However, little is known about how colour information is distributed in these cortical regions. Here, we explored the distribution of colour-selective activity in alert macaque monkeys using functional magnetic resonance imaging (fMRI) with two types of stimuli: a multicoloured ('Mondrian') pattern and an isoluminant colour grating. These two types of stimuli are both commonly used in human fMRI studies, but Mondrian stimuli, which contain a richer variety of hues and hence might be more suitable for activating higher-order areas than grating stimuli, have not been used to examine colour-selectivity in higher-order areas in earlier monkey studies. With the Mondrian stimuli, we observed that areas along the ventral pathway, V1, V2/V3, V4 and the IT cortex, responded more strongly to colour stimuli than to luminance stimuli. In the IT cortex, we found that colour-selective activities are not distributed uniformly, but are localized in discrete regions, each extending several millimetres in the anterior or posterior part of the IT cortex. The colour-selective activation in the anterior IT was observed only with the Mondrian stimuli, whereas the colour-selective activation in the posterior IT was observed with both the Mondrian and grating stimuli, with little overlap. These findings suggest that there are multiple subregions with differing stimulus selectivities distributed in the IT cortex, and that colour information is processed in these discrete subregions. PMID:19912328

Harada, Takuya; Goda, Naokazu; Ogawa, Tadashi; Ito, Minami; Toyoda, Hiroshi; Sadato, Norihiro; Komatsu, Hidehiko



Colour-scent associations in a tropical orchid: three colours but two odours.  


Colour and scent are the major pollinator attractants to flowers, and their production may be linked by shared biosynthetic pathways. Species with polymorphic floral traits are particularly relevant to study the joint evolution of floral traits. We used in this study the tropical orchid Calanthe sylvatica from Réunion Island. Three distinct colour varieties are observed, presenting lilac, white or purple flowers, and named respectively C. sylvaticavar.lilacina (hereafter referred as var. lilacina), C. sylvaticavar. alba (var. alba) and C. sylvatica var. purpurea (var. purpurea). We investigated the composition of the floral scent produced by these colour varieties using the non-invasive SPME technique in the wild. Scent emissions are dominated by aromatic compounds. Nevertheless, the presence of the terpenoid (E)-4,8-dimethylnona-1,3,7-triène (DMNT) is diagnostic of var. purpurea, with the volatile organic compounds (VOC) produced by some individuals containing up to 60% of DMNT. We evidence specific colour-scent associations in C. sylvatica, with two distinct scent profiles in the three colour varieties: the lilacina-like profile containing no or very little DMNT (<2%) and the purpurea-like profile containing DMNT (>2%). Calanthe sylvatica var. alba individuals group with one or the other scent profile independently of their population of origin. We suggest that white-flowered individuals have evolved at least twice, once from var. lilacina and at least once from var. purpurea after the colonisation of la Réunion. White-flowered individuals may have been favoured by the particular pollinator fauna characterising the island. These flowering varieties of C. sylvatica, which display three colours but two scents profiles prove that colour is not always a good indicator of odour and that colour-scent associations may be complex, depending on pollination ecology of the populations concerned. PMID:21377705

Delle-Vedove, Roxane; Juillet, Nicolas; Bessière, Jean-Marie; Grison, Claude; Barthes, Nicolas; Pailler, Thierry; Dormont, Laurent; Schatz, Bertrand



Unexpected patterns of genetic structuring among locations but not colour morphs in Acropora nasuta (Cnidaria; Scleractinia).  


Symbiotic relationships have contributed greatly to the evolution and maintenance of biological diversity. On the Great Barrier Reef, species of obligate coral-dwelling fishes (genus Gobiodon) coexist by selectively recruiting to colonies of Acropora nasuta that differ in branch-tip colour. In this study, we investigate genetic variability among sympatric populations of two colour morphs of A. nasuta ('blue-tip' and 'brown-tip') living in symbiosis with two fish species, Gobiodon histrio and G. quinquestrigatus, respectively, to determine whether gobies are selecting between intraspecific colour polymorphisms or cryptic coral species. We also examine genetic differentiation among coral populations containing both these colour morphs that are separated by metres between local sites, tens of kilometres across the continental shelf and hundreds of kilometres along the Great Barrier Reef. We use three nuclear DNA loci, two of which we present here for the first time for Acropora. No significant genetic differentiation was detected between sympatric colour morphs at these three loci. Hence, symbiotic gobies are selecting among colour morphs of A. nasuta, rather than cryptic species. Significant genetic geographical structuring was observed among populations, independent of colour, at regional (i.e. latitudinal separation by < 500 km) and cross-shelf (< 50 km) scales, alongside relative homogeneity between local populations on within reef scales (< 5 km). This contrasts with the reported absence of large-scale genetic structuring in A. valida, which is a member of the same species group as A. nasuta. Apparent differences in biogeographical structuring between species within the A. nasuta group emphasize the need for comparative sampling across both spatial (i.e. within reefs, between reefs and between regions) and taxonomic scales (i.e. within and between closely related species). PMID:14653784

Mackenzie, J B; Munday, P L; Willis, B L; Miller, D J; van Oppen, M J H



Evolutionary genetics of dorsal wing colour in Colias butterflies  

Microsoft Academic Search

The evolution of butterfly wing colouration is strongly affected by its multiple functions and by the correlated evolution of wing colour elements. Both factors may prevent local adaptation to ecological conditions. We investigated one aspect of wing colouration, the degree of dorsal wing melanization, in the butterfly Colias philodice eriphyle across an elevational gradient and its correlation with another aspect

J. Ellers; C. L. Boggs



Reversals of the colour-depth illusion explained by ocular chromatic aberration.  


Although many colour-depth phenomena are predictable from the interocular difference in monocular chromatic diplopia caused by the eye's transverse chromatic aberration (TCA), several reports in the literature suggest that other factors may also be involved. To test the adequacy of the optical model under a variety of conditions, we have determined experimentally the effects of background colour on perceived monocular chromatic diplopia and perceived depth (chromostereopsis). A Macintosh colour monitor was used to present red, blue, and green test stimuli which were viewed monocularly or binocularly (haploscopically) through 1.78 mm artificial pupils. These apertures were displaced nasally and temporally from the visual axis under controlled conditions to induce a variable degree of TCA. Monocular chromatic diplopia and binocular chromostereopsis were measured for red and blue targets, and also for red and green targets, presented on either a black background or on a background which was composed of the sum of the targets' spectral composition (e.g. red and blue presented on magenta; red and green presented on yellow). In all cases, chromatic diplopia and chromostereopsis were found experimentally to reverse in sign with this change in background. Furthermore, we found that a given coloured target could be located in different depth planes within the same display when located on different background colours. These seemingly paradoxical results could nevertheless be explained by a simple model of optical TCA without the need to postulate additional factors or mechanisms. PMID:7483309

Winn, B; Bradley, A; Strang, N C; McGraw, P V; Thibos, L N



Gender is a major factor explaining discrepancies in eye colour prediction based on HERC2/OCA2 genotype and the IrisPlex model.  


In recent years, several studies have greatly increased our understanding of the genetic basis underlying human eye colour variation. A large percentage of the eye colour diversity present in humans can already be genetically explained, so much so that different DNA-based eye colour prediction models, such as IrisPlex, have been recently developed for forensic purposes. Though these models are already highly accurate, they are by no means perfect, with many genotype-phenotype discrepancies still remaining unresolved. In this work we have genotyped six SNPs associated with eye colour (IrisPlex) in 535 individuals from Spain, a Mediterranean population. Aside from different SNP frequencies in Spain compared to Northern Europe, the results for eye colour prediction are quite similar to other studies. However, we have found an association between gender and eye colour prediction. When comparing similar eye colour genetic profiles, females tend, as a whole, to have darker eyes than males (and, conversely, males lighter than females). These results are also corroborated by the revision and meta-analysis of data from previously published eye colour genetic studies in several Caucasian populations, which significantly support the fact that males are more likely to have blue eyes than females, while females tend to show higher frequencies of green and brown eyes than males. This significant gender difference would suggest that there is an as yet unidentified gender-related factor contributing to human eye colour variation. PMID:23601698

Martinez-Cadenas, Conrado; Peña-Chilet, Maria; Ibarrola-Villava, Maider; Ribas, Gloria



Strange Quark Matter and Colour Superconducting Phases of QCD  

NASA Astrophysics Data System (ADS)

We discuss the evolution of the bubbles of quark matter which survive from the first-order confinement phase transition till the increase of the internal pressure stops their contraction. We also show that at low temperature and high pressure a quark matter composition u d s is preferred to u d d. We finally describe the different colour superconducting phases which may be formed inside neutron stars, and the topological defects that can be generated, where the stable strangelets might be originated and perhaps already detected at high-altitude observatories.

Masperi, Luis



Frequency, phase, and colour coding in apparent motion.  


We present some results which indicate that the known spatiotemporal limits for apparent motion are consistent with the motion being sinusoidal or a result of filtering. Given this we investigated how two such motions interact as a function of their relative temporal phase differences. This was accomplished by inducing two independent motions from complementary coloured event pairs. Results indicated critical phase limits for perceiving the two motions (red and green) which were consistent with the frequency specificity of the effect. The results are discussed within the framework of a filtering process for the perception of apparent motion. PMID:432081

Caelli, T; Finlay, D



The nature of sound and vision in relation to colour  

NASA Astrophysics Data System (ADS)

The increasing role of sound within the visual arts context and the trend in postmodernism towards interdisciplinary artworks has demanded a heightened awareness of the audio-visual. This paper explores some of the fundamental physical properties of both sound and colour, their similarities and differences and how the audio and visual senses are related. Ways in which soundscapes have been combined with paintings in exhibitions by the author will be used to illustrate how the two media can be combined to enhance the overall artistic experience.

Greated, Marianne



Principal component analysis and neurocomputing-based models for total ozone concentration over different urban regions of India  

NASA Astrophysics Data System (ADS)

The present study deals with daily total ozone concentration time series over four metro cities of India namely Kolkata, Mumbai, Chennai, and New Delhi in the multivariate environment. Using the Kaiser-Meyer-Olkin measure, it is established that the data set under consideration are suitable for principal component analysis. Subsequently, by introducing rotated component matrix for the principal components, the predictors suitable for generating artificial neural network (ANN) for daily total ozone prediction are identified. The multicollinearity is removed in this way. Models of ANN in the form of multilayer perceptron trained through backpropagation learning are generated for all of the study zones, and the model outcomes are assessed statistically. Measuring various statistics like Pearson correlation coefficients, Willmott's indices, percentage errors of prediction, and mean absolute errors, it is observed that for Mumbai and Kolkata the proposed ANN model generates very good predictions. The results are supported by the linearly distributed coordinates in the scatterplots.

Chattopadhyay, Goutami; Chattopadhyay, Surajit; Chakraborthy, Parthasarathi



Empirical analysis of the relationship between total consumption-GDP ratio and per capita income for different metals : The cases of Brazil, China and India  

Microsoft Academic Search

Purpose – The main purpose of the paper is to propose an empirical analysis of the relationship between total consumption of different key metals (aluminium, copper, lead, nickel, tin and zinc) and per capita income of some important developing countries (Brazil, China and India) today present in the international scenario with very different perspectives from in the past. Design\\/methodology\\/approach –

Antonio Focacci



Colour and surface fluorescence development and their relationship with Maillard reaction markers as influenced by structural changes during cornflakes production.  


The aim of this work was to study colour and surface fluorescence development in relation to the chemical markers for the Maillard reaction at the cooking, flaking and toasting stages of cornflake production process. Colour was measured by a calibrated computer vision system. Surface fluorescence was measured on compressed samples. Aqueous extracted Maillard reaction markers (hydroxymethylfurfural, carboxymethyl-lysine, absorbance at 420nm and total fluorescence) were measured on protease hydrolyzed samples. Sample microstructure was observed by scanning electron microscopy. During cooking the colour coordinates L(?) and b(?) decreased and a(?) increased. After flaking, the samples appeared lighter, while the pigment concentration, fluorescence and hydroxymethylfurfural did not change. Toasting generated bubbles in the matrix and L(?) apparently increased, although brown pigment concentration increased. Pigment concentration did not correlate with surface colour due to the destruction or generation of interfaces. Surface and microstructure effects can be avoided by milling and compressing the samples. PMID:22953910

Farroni, Abel; Buera, María Del Pilar



Simultaneous removal of colour, phosphorus and disinfection from treated wastewater using an agent synthesized from amorphous silica and hydrated lime.  


An agent synthesized from amorphous silica and hydrated lime (CSH-lime) was investigated for its ability to simultaneously remove the colour, phosphorus and disinfection from the effluents from wastewater treatment plants on swine farms. CSH-lime removed the colour and phosphate from the effluents, with the colour-removal effects especially high at pH 12, and phosphorous removal was more effective in strongly alkaline conditions (pH > 10). Colour decreased from 432 +/-111 (mean +/- SD) to 107 +/- 41 colour units and PO4(3-)P was reduced from 45 +/- 39 mg/L to undetectable levels at the CSH-lime dose of 2.0% w/v. Moreover, CSH-lime reduced the total organic carbon from 99.0 to 37.9 mg/L at the dose of 2.0% w/v and was effective at inactivating total heterotrophic and coliform bacteria. However, CSH-lime did not remove nitrogen compounds such as nitrite, nitrate and ammonium. Colour was also removed from dye solutions by CSH-lime, at the same dose. PMID:23837353

Yamashita, Takahiro; Aketo, Tsuyoshi; Minowa, Nobutaka; Sugimoto, Kiyomi; Yokoyama, Hiroshi; Ogino, Akifumi; Tanaka, Yasuo



Effect of ripeness and postharvest storage on the evolution of colour and anthocyanins in cherries ( Prunus avium L.)  

Microsoft Academic Search

The relationship between colour parameters and anthocyanins of four sweet cherry cultivars, Burlat, Saco, Summit and Van was studied. The colour (L?, a?, b?, chroma and hue angle parameters) and anthocyanins were analysed during two different years at two different ripening stages (partially ripe, and ripe, respectively). The cherries were analysed at harvest and after storage at 1.5±0.5°C and 15±5°C

Berta Gonçalves; Ana Paula Silva; José Moutinho-Pereira; Eunice Bacelar; Eduardo Rosa; Anne S. Meyer



The coding of uniform colour figures in monkey visual cortex  

PubMed Central

Psychophysical studies indicate that perception of the colour and brightness of a surface depends on neural signals evoked by the borders of the surface rather than its interior. The visual cortex emphasizes contrast borders, but it is unclear whether colour surface signals also exist, whether colour border signals are orientation selective or mainly non-oriented, and whether cortical processing tends to separate colour and form information. To address these questions we examined the representation of uniform colour figures by recording single neuron activity from areas V1 and V2 in alert macaque monkeys during behaviourally induced fixation. Three aspects of coding were quantified: colour, orientation and edge selectivity. The occurrence of colour selectivity was not correlated with orientation or edge selectivity. The fraction of colour-selective cells was the same (64 % in layers 2 and 3 of V1, 45 % in V2) for oriented and non-oriented cells, and for edge-selective and surface-responsive cells. Oriented cells were often highly selective in colour space, and about 40 % of them were selective for edge polarity or border ownership. Thus, contrary to the idea of feature maps, colour, orientation and edge polarity are multiplexed in cortical signals. The results from V2 were similar to those from upper-layer V1, indicating that cortical processing does not strive to separate form and colour information. Oriented cells were five times more frequent than non-oriented cells. Thus, the vast majority of colour-coded cells are orientation tuned. Based on response profiles across a 4 deg square figure, and the relative frequency of oriented and non-oriented cells, we estimate that the cortical colour signal is 5–6 times stronger for the edges than for the surface of the figure. The frequency of oriented colour cells and their ability to code edge polarity indicate that these cells play a major role in the representation of surface colour.

Friedman, Howard S; Zhou, Hong; von der Heydt, Rudiger



Total and soluble oxalate content of some Indian spices.  


Spices, such as cinnamon, cloves, cardamom, garlic, ginger, cumin, coriander and turmeric are used all over the world as flavouring and colouring ingredients in Indian foods. Previous studies have shown that spices contain variable amounts of total oxalates but there are few reports of soluble oxalate contents. In this study, the total, soluble and insoluble oxalate contents of ten different spices commonly used in Indian cuisine were measured. Total oxalate content ranged from 194 (nutmeg) to 4,014 (green cardamom) mg/100 g DM, while the soluble oxalate contents ranged from 41 (nutmeg) to 3,977 (green cardamom) mg/100 g DM. Overall, the percentage of soluble oxalate content of the spices ranged from 4.7 to 99.1% of the total oxalate content which suggests that some spices present no risk to people liable to kidney stone formation, while other spices can supply significant amounts of soluble oxalates and therefore should be used in moderation. PMID:22492273

Ghosh Das, Sumana; Savage, G P



Changes in VO2 Max. Resulting from Bicycle Training at Different Intensities Holding Total Mechanical Work Constant.  

ERIC Educational Resources Information Center

Effects of different training intensities on oxygen intake were determined in this study. Sixteen male subjects aged 16-18 were randomly assigned to one of three training groups or a control group. The training groups trained 3 days per week on bicycle ergometers at different intensities (85 percent, 75 percent, or 65 percent of heart rate…

Burke, Edmund A., Jr.; Franks, B. Don


Effect of Chloride and Sulfate Salinity on Micronutrients Release and Uptake from Different Composts Applied on Total Phosphorus Basis  

Microsoft Academic Search

Generation of different biowastes is increasing day by day, and ultimate load on agricultural lands has increased. Concerns over increased phosphorus (P) application with nitrogen (N)–based compost application shifted the trend to P?based applications. But focus on only one or two nutritional elements will not serve the goals of sustainable agriculture. Full insight into nutrient availability from different composts is

Zahoor Ahmad; Toshimasa Honna; Sadahiro Yamamoto; Faridullah; Muhammad Irshad



Fluctuating selection by water level on gynoecium colour polymorphism in an aquatic plant  

PubMed Central

Background and Aims It has been proposed that variation in pollinator preferences or a fluctuating environment can act to maintain flower colour polymorphism. These two hypotheses were tested in an aquatic monocot Butomus umbellatus (Butomaceae) with a pink or white gynoecium in the field population. Methods Pollinator visitation was compared in experimental arrays of equivalent flowering cymes from both colour morphs. Seed set was compared between inter- and intramorph pollination under different water levels to test the effect of fluctuating environment on seed fertility. Key Results Overall, the major pollinator groups did not discriminate between colour morphs. Compared with the white morph, seed production in the pink morph under intermorph, intramorph and open pollination treatments was significantly higher when the water level was low but not when it was high. Precipitation in July was correlated with yearly seed production in the pink morph but not in the white morph. Conclusions The results indicated that the two colour morphs differed in their tolerance to water level. Our study on this aquatic plant provides additional evidence to support the hypothesis that flower colour polymorphism can be preserved by environmental heterogeneity.

Tang, Xiao-Xin; Huang, Shuang-Quan



Field trial of a haemoglobin colour scale: an effective tool to detect anaemia in preschool children.  


The objective of this study was to evaluate the performance of the Haemoglobin Colour Scale, developed by Stott and Lewis, to diagnose anaemia in a primary health care setting where anaemia was prevalent and severe. Three measures of anaemia were compared in 535 preschool children: haemoglobin based on the Haemoglobin Colour Scale, clinical assessment in three sites (conjunctiva, palm and nail bed) and haemoglobin based on a digital haemoglobinometer (HemoCue method) taken as gold standard. A statistically significant correlation (r = 0.80, coefficient = 0.77 and Y intercept = 2.33) was obtained between the results of the Haemoglobin Colour Scale and the HemoCue. In more than 80% of cases, the difference between the colour scale readings and the results of the HemoCue was within 1 g/dl. Of 415 anaemic children (Hb < 11 g/dl by HemoCue), 85.2% were so identified by the Haemoglobin Colour Scale and 19.7% were classified anaemic by clinical pallor. Of 19 severely anaemic children (Hb < 7 g/dl by HemoCue), 73.6% were identified as severely anaemic and 100% were classified as anaemic by the colour scale, 61.1% were classified as anaemic using clinical pallor. We found the Haemoglobin Colour Scale to be a useful tool in identifying anaemic and severely anaemic children. Efficiencies in term of cost, accuracy and time make it an important resource in primary health care settings in developing countries. Further testing with other staff in other settings is recommended to determine the usefulness of large-scale distribution. PMID:10747273

Montresor, A; Albonico, M; Khalfan, N; Stoltzfus, R J; Tielsch, J M; Chwaya, H M; Savioli, L



Impaired colour discrimination among workers exposed to styrene: relevance of a urinary metabolite.  

PubMed Central

OBJECTIVES--To survey the loss of colour vision among Japanese workers who have been exposed to styrene concentrations currently considered low (about 20 ppm). Also to assess the effects of styrene by examination of the nature of the relation between disorder of colour vision and age, alcohol consumption, and other variables. METHODS--Colour discrimination was examined in 64 male workers exposed to styrene (mean age; 38.0, mean exposed years; 7.0) and in 69 controls (mean age; 38.0). A standardised questionnaire was adopted to collect work history, occupational or non-occupational solvent exposure, alcohol consumption, and drug use. Colour vision was evaluated by the Lanthony desaturated panel D-15 test. The results of the test were expressed as the colour confusion index (CCI). RESULTS--The mean atmospheric styrene concentration was about 20 ppm. The mean urinary concentration of mandelic acid was 0.22 g/l. There was a significant difference in CCI between exposed workers and age matched controls. Colour vision of workers whose concentration of urinary mandelic acid was > or = 0.42 g/l was significantly impaired when compared with workers whose concentration was < 0.42 g/l. Multiple linear regression analysis that controlled confounding variables such as age, alcohol consumption, smoking, and educational attainment showed that the CCI was significantly related to the concentration of urinary mandelic acid. In both exposed workers and controls, the types of defects were mostly blue-yellow loss, although a few subjects showed complex loss. No one showed only red-green loss. CONCLUSIONS--These findings suggest that exposure to moderate styrene concentrations can lead to impairment of colour vision, and that there is a significant correlation with the urinary metabolite of styrene.

Eguchi, T; Kishi, R; Harabuchi, I; Yuasa, J; Arata, Y; Katakura, Y; Miyake, H



Scent and Colour in Flowers  

Microsoft Academic Search

THE extension of our perceptive faculties of sight and hearing by various optical and acoustical instruments may enable us to comprehend the possibility of these faculties existing in other creatures to a degree so far surpassing ours as to seem a difference almost of kind. So the sight of the vulture would seem to be paralleled by the faculty of

G. S. Boulger



Skin colour of the Ainu of Hidaka, Hokkaido, Northern Japan.  


Quantitative data on skin colour variation are presented for Ainu of the Hidaka District, Hokkaido. Measurements of upper arm reflectance were taken using 8 filters of an EEL reflectance spectrophotometer. The results are compared with those published for the Japanese by Hulse (1976). Sexual dimorphism is well marked in both populations and among the Ainu appears to be due largely to clothing habits. There is no statistical evidence for an association between skin colour and age. Ainu reflectance values at 545 nm and antilog transforms at 685 nm lie between those reported for Eskinomos of Greenland and Brazilian whites. Although the Ainu have consistently higher reflectance values than a Japanese sample assigned to the northern part of Japan, the results give little indication of the relative contributions of genetic and environmental factors to the differences observed. However, comparison of mean reflectance for Hokkaido Ainu and 'Central' Japanese with values predicted on the basis of world trends indicates that the differences are no greater than would be expected for two populations separated by over 7 degrees latitude and differing from one another in respect of temperature and humidity. Correspondence between observed and predicted reflectance values is excellent at the longest wavelength but poor at 470 nm. PMID:727704

Harvey, R G; Lord, J M



Total mercury distribution in different tissues of six species of freshwater fish from the Kpong hydroelectric reservoir in Ghana.  


Total mercury concentrations were determined in seven tissues of 38 fish samples comprising six species from the Kpong hydroelectric reservoir in Ghana by cold vapour atomic absorption spectrometry technique using an automatic mercury analyzer. Mercury concentration in all the tissues ranged from 0.005 to 0.022 ?g/g wet weight. In general, the concentration of mercury in all the tissues were decreasing in the order; liver?>?muscle?>?intestine?>?stomach?>?gonad?>?gill?>?swim bladder. Mercury concentration was generally greater in the tissues of high-trophic-level fish such as Clarotes laticeps, Mormyrops anguilloides and Chrysichthys aurutus whereas low-trophic-level fish such as Oreochromis niloticus recorded low mercury concentration in their tissues. The results obtained for total mercury concentration in the muscle tissues analysed in this study are below the WHO/FAO threshold limit of 0.5 ?g/g. This suggests that the exposure of the general public to Hg through fish consumption can be considered negligible. PMID:21713471

Atta, Alhassan; Voegborlo, Ray Bright; Agorku, Eric Selorm



Genomic relationships between Enterococcus faecium strains from different sources and with different antibiotic resistance profiles evaluated by restriction endonuclease analysis of total chromosomal DNA using EcoRI and PvuII.  


Forty-seven Enterococcus faecium strains from different sources were evaluated by restriction endonuclease analysis (REA) of total chromosomal DNA. Strains from chicken, pork, and humans were clearly divided into separate clusters, whereas strains from different countries, strains with different antibiotic resistance profiles, or clinical and healthy-subject strains were not. PMID:10103281

Quednau, M; Ahrné, S; Molin, G



Genomic Relationships between Enterococcus faecium Strains from Different Sources and with Different Antibiotic Resistance Profiles Evaluated by Restriction Endonuclease Analysis of Total Chromosomal DNA Using EcoRI and PvuII  

PubMed Central

Forty-seven Enterococcus faecium strains from different sources were evaluated by restriction endonuclease analysis (REA) of total chromosomal DNA. Strains from chicken, pork, and humans were clearly divided into separate clusters, whereas strains from different countries, strains with different antibiotic resistance profiles, or clinical and healthy-subject strains were not.

Quednau, M.; Ahrne, S.; Molin, G.




Microsoft Academic Search

Ocular filters in the eyes of many vertebrates, including humans, absorb wavelengths shorter than approximately 400 nm. These filters prevent the ?-band of a visual pigment from being exposed to ultraviolet radiation, essentially narrowing the spectral sensitivity of the different photoreceptor classes. A comparison of different hypothetical visual systems is used to show that von Kries colour constancy is improved



Physiological variation related to shell colour polymorphism in White Sea Littorina saxatilis  

Microsoft Academic Search

Responses to moderate and extreme salinity change were investigated in White Sea Littorina saxatilis of different genetically determined shell colour morphs in order to test a hypothesis about physiological selection as a driving force of the change of phenotypic structure of this species along a salinity gradient in White Sea estuaries. Some of the studied physiological responses did not differ

I. M. Sokolova; V. Ja Berger



Colour appearance descriptors for image browsing and retrieval  

NASA Astrophysics Data System (ADS)

In this paper, we focus on the development of whole-scene colour appearance descriptors for classification to be used in browsing applications. The descriptors can classify a whole-scene image into various categories of semantically-based colour appearance. Colour appearance is an important feature and has been extensively used in image-analysis, retrieval and classification. By using pre-existing global CIELAB colour histograms, firstly, we try to develop metrics for whole-scene colour appearance: "colour strength", "high/low lightness" and "multicoloured". Secondly we propose methods using these metrics either alone or combined to classify whole-scene images into five categories of appearance: strong, pastel, dark, pale and multicoloured. Experiments show positive results and that the global colour histogram is actually useful and can be used for whole-scene colour appearance classification. We have also conducted a small-scale human evaluation test on whole-scene colour appearance. The results show, with suitable threshold settings, the proposed methods can describe the whole-scene colour appearance of images close to human classification. The descriptors were tested on thousands of images from various scenes: paintings, natural scenes, objects, photographs and documents. The colour appearance classifications are being integrated into an image browsing system which allows them to also be used to refine browsing.

Othman, Aniza; Martinez, Kirk



Spectral imaging system for non-contact colour measurement  

NASA Astrophysics Data System (ADS)

This paper describes the development of a non-contact system for measuring colour of printed material at web speeds. The system proposed uses a non-contact spectrophotometer based on a holographic grating, in conjunction with a conventional monochrome area scan camera, from which colour spectral data is extracted, whilst a xenon flash is used to illuminate colour samples. Software and hardware details of the system are given, along with the underlying mathematics for colour space conversion and measurement. Conversion equations from X, Y, Z chromaticity co-ordinates to the RGB system are presented, and also equations to convert from the L ?a ?b ? colour space to X, Y, Z chromaticity co-ordinates. Experimental results are presented whereby the non-contact spectral system is shown to perform to a colour tolerance exceeding that of conventional colour video systems.

Brown, N.; Peng, J.; Jackson, M. R.; Parkin, R. M.



Colour biases in territorial aggression in a Neotropical cichlid fish.  


Discrete colour morphs have provided important insights into the evolution of phenotypic diversity. One of the mechanisms that can help to explain coexistence of ecologically similar colour morphs and incipient species is (colour) biased aggression, which has the potential to promote continued existence of the morphs in a frequency-dependent manner. I addressed colour biases in territorial aggression in a field-based study on a Neotropical cichlid fish species, Amphilophus sagittae, which has two ecologically indistinguishable colour morphs that mate assortatively. I found that A. sagittae, in particular females, were more aggressive towards models of their own colour than those mimicking colours of the other morph. Such a behavioural pattern should result in a selection regime that benefits the rarer morph, and hence could help explain how novel, rare phenotypes may avoid competitive exclusion. PMID:24414236

Lehtonen, Topi K



The multiple disguises of spiders: web colour and decorations, body colour and movement  

PubMed Central

Diverse functions have been assigned to the visual appearance of webs, spiders and web decorations, including prey attraction, predator deterrence and camouflage. Here, we review the pertinent literature, focusing on potential camouflage and mimicry. Webs are often difficult to detect in a heterogeneous visual environment. Static and dynamic web distortions are used to escape visual detection by prey, although particular silk may also attract prey. Recent work using physiological models of vision taking into account visual environments rarely supports the hypothesis of spider camouflage by decorations, but most often the prey attraction and predator confusion hypotheses. Similarly, visual modelling shows that spider coloration is effective in attracting prey but not in conveying camouflage. Camouflage through colour change might be used by particular crab spiders to hide from predator or prey on flowers of different coloration. However, results obtained on a non-cryptic crab spider suggest that an alternative function of pigmentation may be to avoid UV photodamage through the transparent cuticle. Numerous species are clearly efficient locomotory mimics of ants, particularly in the eyes of their predators. We close our paper by highlighting gaps in our knowledge.

Thery, Marc; Casas, Jerome



Radiobiological modeling of combined targeted [sup 131]I therapy and total body irradiation for treatment of disseminated tumors of differing radiosensitivity  

SciTech Connect

A model is presented for calculating combinations of targeted [sup 131]I and total body irradiation, followed by bone marrow rescue, in the treatment of tumors of different radiosensitivity. The model is used to evaluate the role of the total body irradiation component in the optimal combination regime as a function of the radiosensitivity of the tumor cells. A microdosimetric model was used to calculate absorbed dose in small tumors and micrometastases when uniformly targeted by the radionuclide [sup 131]I. Cell kill was calculated from absorbed dose using an extended version of the linear quadratic model. The addition of varying total doses of total body irradiation, assuming 2 Gy fractions, was also calculated using the linear quadratic model. The net cell kill from combined modality (targeted [sup 131]I and total body irradiation) was computed for varying proportions of the two components, for a range of tumor sizes, restricting the total radiation dose to within tolerance for a full-course TBI regime ([approximately] 14 Gy total) in all cases. The calculations were repeated for a range of presumed tumor uptakes of the targeting agent and for a range of tumor radiosensitivities, typical of those reported for tumor cells of differing type in culture. Optimal regimes were identified as those predicted to yield a high probable tumor cure rate (evaluated using a Poisson statistical model) for all tumor sizes. The analysis supports earlier model studies which predicted that systemic combination treatment with targeted [sup 131]I and total body irradiation would be superior to either component used alone. The intrinsic tumor radiosensitivity is found to be a factor which influences the optimal combination of the [sup 131]I and external beam total body irradiation components. 20 refs., 8 figs., 3 tabs.

Amin, A.E.; Wheldon, T.E.; O'Donoghue, J.A.; Barrett, A. (Univ. of Glasgow (United Kingdom))



Tensor Processing for Texture and Colour Segmentation  

Microsoft Academic Search

\\u000a In this paper, we propose an original approach for texture and colour segmentation based on the tensor processing of the nonlinear\\u000a structure tensor. While the tensor structure is a well established tool for image segmentation, its advantages were only partly\\u000a used because of the vector processing of that information. In this work, we use more appropriate definitions of tensor distance

Rodrigo De Luis García; Rachid Deriche; Mikaël Rousson; Carlos Alberola-lópez



Designs for two-colour microarray experiments  

Microsoft Academic Search

Designs for two-colour microarray experiments can be viewed as block designs with two treatments per block. Explicit formulae for the A- and D-criteria are given for the case that the number of blocks is equal to the number of treatments. These show that the A- and D-optimality criteria conflict badly if there are 10 or more treatments. A similar analysis

R. A. Bailey



Colour Phenomena in Ultra-Violet Vision  

Microsoft Academic Search

THE note by N. I. Pinegin1 suggests a more detailed discussion of the relation between the threshold intensities for scotopic and photopic vision in the ultra-violet. The threshold ratio Tp\\/Ts is a measure of the intensity range, often misleadingly called `photochromatic interval', in which the visual impression is free from the specific colour sensation. This intensity range is a marked

E. E. Schneider



Colour Magnitude Diagrams of Transiting Exoplanets  

NASA Astrophysics Data System (ADS)

Colour-Magnitude diagrams form a traditional way of representing luminous objects in the Universe and compare them to each others. Here, the photometric distances of 44 transiting exoplanetary systems were estimated. For seven of those, parallaxes confirm the methodology. From the combination of those measurements with fluxes obtained while planets were occulted by their host stars, colour-magnitude diagrams are composed in the near and mid IR. When possible, planets are plotted with field brown dwarfs who often have similar sizes and equilibrium temperatures, thus offering a natural empirical comparison sample. Exoplanets are also compared to the expected loci of pure blackbodies. In general planets do not agree with the brown dwarfs sequences, and neither do they match blackbodies. It is however possible to affirm that they are not featureless and that they display an increasing diversity in colour with decreasing intrinsic luminosity. A missing source of absorption within the [4.5 ?m] band, for some planets, would generally reconcile hot Jupiters with brown dwarfs’ cool atmospheres. Alternatively, measuring the emission of gas giants cooler than 1 000 K would disentangle whether planets’ atmospheres behave like brown dwarfs’ atmospheres, like blackbodies, or whether they form their own sequence.

Triaud, Amaury H. M. J.



Adding New Colours to Interferometry  

NASA Astrophysics Data System (ADS)

Another vital step has been accomplished as planned towards full operation of the ESO Very Large Telescope Interferometer (VLTI) at the Paranal Observatory in Chile, one of the world's foremost astronomical facilities. In the night of March 20-21, 2004, a team of astronomers and engineers from France, Italy, Germany and ESO celebrated the successful assembly and completion of the first on-line tests of the latest of the first-generation VLTI instruments, the Astronomical Multiple BEam Recombiner (AMBER). They combined the two beams of light from the southern star Theta Centauri from two test telescopes ("siderostats" with 40-cm aperture, cf. ESO PR 06/01) to produce strong and clear interferometric fringes. Equally successful observations were then obtained on the bright star Sirius, and consistently repeated during the following nights. A joint project This is the most promising result of about 7 years of dedicated work by a team of over 40 astronomers and engineers. The AMBER instrument has been developed by a European consortium of seven research institutes in three ESO member countries, the main partners being: Laboratoire d'Astrophysique de Grenoble (LAOG), Laboratoire Universitaire d'Astrophysique de Nice (LUAN) and Observatoire de la Côte d'Azur in France, Max-Planck-Institut für Radioastronomie (MPIfR) in Bonn, Germany, and Osservatorio Astrofisico di Arcetri (OAA; part of INAF, the Italian National Institute for Astrophysics) in Florence, Italy. The total cost of AMBER is of the order of 5.9 million Euros, mostly contributed by the members of the consortium. It was built through an agreement with ESO, which rewards the consortium solely with guaranteed observing time. According to the contract, the consortium will receive 60 observing nights to be spread among two or three of the four 8.2-m VLT Unit Telescopes and 130 nights with the four Auxiliary Telescopes over a period of eight years. AMBER: soon to join three light beams at once ESO PR Photo 09a/04 ESO PR Photo 09a/04 AMBER at the VLT Interferometric Laboratory [Preview - JPEG: 534 x 400 pix - 68k] [Normal - JPEG: 1067 x 800 pix - 665k] Caption: ESO PR Photo 09a/04 shows the AMBER instrument in the VLT Interferometric Laboratory at Paranal. The AMBER instrument is mounted on a 4.2 x 1.5 m precision optical table, placed in the VLT Interferometric Laboratory at the top of the Paranal mountain, cf. PR Photo 09/04. The total shipping weight of the instrument and its extensive associated electronics was almost 4 tons. AMBER is the latest addition to the VLTI and completes the planned set of first-generation instruments for this facility. It continues the success story of the interferometric mode of the VLT, following the unique initial scientific results obtained by the VINCI and MIDI instruments, the installation of the first MACAO adaptive optics systems and the recent arrival of the first 1.8-m Auxiliary Telescope at Paranal (ESO PR 01/04). The interferometric technique can achieve images, as sharp as those of a telescope with a diameter equivalent to the distance between the telescopes in the interferometer. For the VLTI, this distance can be as large as 205 meters, resulting in a resolution of 0.001 arcsec in the near-infrared spectral region (at 1 ?m wavelength). The latter measure corresponds to about 2 metres on the surface of the Moon. AMBER is a very powerful complement to the other instruments already installed at the VLTI and offered to the astronomical community. AMBER is indeed sensitive in the near-infrared wavelength region of 1 to 2.5 microns while the present instrument, MIDI, covers the 8 to 13 microns range. Moreover, AMBER will be able to perform spectroscopic measurements with a spectral resolution up to 10,000. ESO PR Photo 09b/04 ESO PR Photo 09b/04 The AMBER instrument (detail) [Preview - JPEG: 435 x 400 pix - 74k] [Normal - JPEG: 870 x 800 pix - 722k] Caption: ESO PR Photo 09b/04 shows in the foreground some of the mirrors and optical fibers (yellow cables), as well as the dichroic mirrors by means of which the light beams



Recovery and characterisation of coloured phenolic preparations from apple seeds.  


The aim of this study was to investigate whether complexly constituted phenolic extracts from apple seeds may be utilised for the recovery of natural coloured antioxidant preparations, which might serve as potential food or cosmetic ingredients. In a first step, the recovery of phenolic compounds was optimised by varying crucial extraction parameters. A single extraction step at 25°C using an acetone-water mixture (60:40, v/v) and a solid-to-solvent ratio of 1:8 (w/v) for 1 h was found to be appropriate to achieve both high phenolic yields and antioxidant activities. In a second step, differently produced apple seed extracts and a phloridzin model solution were enzymatically treated by mushroom polyphenol oxidase to investigate the rate of pigment synthesis. Depending on the extraction procedure applied, synthesis rates, pigment yields and colour properties significantly differed. Compared to the phloridzin model solution, extracts recovered from the seeds showed comparable and even better results, thus indicating such preparations to be a promising alternative to synthetic yellow dyes. PMID:23194524

Fromm, Matthias; Loos, Helene M; Bayha, Sandra; Carle, Reinhold; Kammerer, Dietmar R



The calculation of small molecular interactions by the differences of separate total energies. Some procedures with reduced errors  

Microsoft Academic Search

A new direct difference method for the computation of molecular interactions has been based on a bivariational transcorrelated treatment, together with special methods for the balancing of other errors. It appears that these new features can give a strong reduction in the error of the interaction energy, and they seem to be particularly suitable for computations in the important region

S. F. Boys; F. Bernardi



The Effectiveness of a Total Environment Room on an Early Reading Program for Culturally Different Pre-School Children.  

ERIC Educational Resources Information Center

The purpose of this study was to measure the gains that culturally different 4-year-old children made in reading readiness activities and the acquisition of a sight vocabulary when exposed to an extensive prekindergarten reading intervention program. The subjects of the study were selected initially from a group of volunteer families. The subjects…

Peta, Erminio Joseph


Eavesdropping cuckoos: further insights on great spotted cuckoo preference by magpie nests and egg colour.  


Reproductive success of brood parasites largely depends on appropriate host selection and, although the use of inadvertent social information emitted by hosts may be of selective advantage for cuckoos, this possibility has rarely been experimentally tested. Here, we manipulated nest size and clutch colouration of magpies (Pica pica), the main host of great spotted cuckoos (Clamator glandarius). These phenotypic traits may potentially reveal information about magpie territory and/or parental quality and could hence influence the cuckoo's choice of host nests. Experimentally reduced magpie nests suffered higher predation rate, and prevalence of cuckoo parasitism was higher in magpie nests with the densest roofs, which suggests a direct advantage for great spotted cuckoos choosing this type of magpie nest. Colouration of magpie clutches was manipulated by adding one artificial egg (blue or cream colouration) at the beginning of the egg-laying period. We found that host nests holding an experimental cream egg experienced a higher prevalence of cuckoo parasitism than those holding a blue-coloured egg. Results from these two experiments suggest that great spotted cuckoos cue on magpie nest characteristics and the appearance of eggs to decide parasitism, and confirm, for the first time, the ability of cuckoos to distinguish between eggs of different colours within the nest of their hosts. Several hypothetical scenarios explaining these results are discussed. PMID:24556949

Soler, Juan J; Avilés, Jesús M; Martín-Gálvez, David; de Neve, Liesbeth; Soler, Manuel



A Rapid tool for the stability assessment of natural food colours.  


Natural food colours lack stability under a number of conditions such as pH variation, oxidation, hydration, heat treatment and, most importantly, exposure to daylight. Stability tests to assess shelf life of natural colours under light irradiation can be time consuming. Thus, an accelerated test carried out under high light intensity irradiation that can be related to normal daylight irradiation conditions is highly desirable. Samples of various natural colouring solutions were prepared in aqueous model matrices at a range of pH values to mimic the majority of food matrices, pasteurised and irradiated under normal D65 light (0.2 W/m(2)) at 25°C, and in parallel under high light intensity irradiation (30 W/m(2)) at 3 different temperatures (25, 35 and 45°C). Similarly to the already known Q10 parameters for temperature, acceleration factors QL for irradiation, were determined and used for the first time to obtain a link between colour degradation under normal and accelerated conditions. It was possible, using these acceleration factors, to greatly reduce the time required to predict and compare the shelf life stability for a series of natural colours in aqueous model systems. PMID:23561199

Ghidouche, Souhila; Rey, Brigitte; Michel, Martin; Galaffu, Nico



Colouration mechanism of underglaze copper-red decoration porcelain (AD 13th-14th century), China.  


Underglaze copper-red decoration, i.e. the copper colourant used to paint diversified patterns on the surface of a body and then covered by transparent glaze and fired at high temperature in a reductive firing environment, is famous all over the world. However, the red colouration mechanism generated by underglaze copper remains unclear. In particular, the fact that the edges of the red patterns are orange has been ignored in previous research. Here, non-destructive analysis has been carried out on a precious fragment of early underglaze red porcelain using synchrotron radiation X-ray fluorescence, X-ray absorption near-edge spectroscopy (XANES) and reflection spectrometry techniques. The results suggest that the copper content in the red region is higher than that in the orange region, and other colour generation elements do not have obvious content difference, indicating that the colour generation effect of the underglaze red product is related to the copper content. XANES analysis shows that the valence states of copper in the red and orange regions are similar and metal copper contributes to their hues. The results of reflection spectrometry demonstrate that tiny orange hues could be attributed to the Mie scatting effect. Therefore, light-scattering effects should be considered when researching the colouration mechanism of underglaze red. PMID:24971970

Zhu, Jian; Duan, Huiping; Yang, Yimin; Guan, Li; Xu, Wei; Chen, Dongliang; Zhang, Jing; Wang, Lihua; Huang, Yuying; Wang, Changsui



Visual habitat geometry predicts relative morph abundance in the colour-polymorphic ornate rainbowfish  

PubMed Central

During colour signalling in aquatic environments, the colour of the ambient light, the background against which signals are viewed and signal transmission through the environment can all have profound impacts on the efficacy of a given signal. In colour-polymorphic species, where alternative morphs persist owing to a balance in the natural and sexual selection for each, changes to the visual context can have large effects on the local success and relative abundance of competing phenotypes. The ornate rainbowfish, Rhadinocentrus ornatus, is composed of populations that vary in the relative frequency of red and blue individuals, and inhabit sites that vary in water transmittance from clear (white) to heavily tannin-stained (red-shifted). Using spectroradiometry, we measured the downwelling and sidewelling irradiance, bank radiance and water transmittance of 10 R. ornatus habitats. We found that the relative local abundance of each morph was predicted not by water transmittance but by chromatic differences between the vertical (downwelling light) and horizontal (bank colour) components of the habitat. This visual habitat geometry should increase contrast between the colour signal and background, with large potential to influence the strength of natural and sexual selection in this system.

Hancox, Daniel; Wilson, Robbie S.; White, Craig R.



Content of polyphenols in coloured and yellow fleshed potatoes during dices processing.  


The purpose of the research was to examine the effect of the laboratory production of dried potato dice on the content of phenolic compounds in one yellow-fleshed potato variety and four blue-fleshed potatoes varieties. Coloured-flesh potato varieties were characterised by about three times higher amount of total phenolic content than traditional yellow-fleshed ones. The predominating phenolic acids in potato were chlorogenic acid and its isomers, which account about 90% of total phenolic content in tubers. The phenolic acid content decreased by 80% after peeling the blue-fleshed potatoes and by 60% after peeling the yellow variety. The dried potato dice obtained from yellow-fleshed potatoes had no content of phenolic acids but produced from colour-fleshed potatoes contained about 4% of the original phenolic content of the raw material. Chlorogenic acid amounted about 97% of total phenolic acid content, and the rest was neochlorogenic acid. PMID:24837944

Rytel, E; Tajner-Czopek, A; Kita, A; Anio?owska, M; Kucharska, A Z; Sokó?-??towska, A; Hamouz, K



Understanding the differences between the wear of metal-on-metal and ceramic-on-metal total hip replacements.  


Hip simulator studies have been carried out extensively to understand and test artificial hip implants in vitro as an efficient alternative to obtaining long-term results in vivo. Recent studies have shown that a ceramic-on-metal material combination lowers the wear by up to 100 times in comparison with a typical metal-on-metal design. The reason for this reduction remains unclear and for this reason this study has undertaken simple tribometer tests to understand the fundamental material loss mechanisms in two material combinations: metal-on-metal and ceramic-on-ceramic. A simple-configuration reciprocating pin-on-plate wear study was performed under open-circuit potential (OCP) and with applied cathodic protection (CP) in a serum solution using two tribological couples: firstly, cobalt-chromium (Co-Cr) pins against Co-Cr plates; secondly, Co-Cr pins against alumina (Al2O3) plates. The pin and plate surfaces prior to and after testing were examined by profilometry and scanning electron microscopy. The results showed a marked reduction in wear when CP was applied, indicating that total material degradation under the OCP condition was attributed to corrosion processes. The substitution of the Co-Cr pin with an Al2O3 plate also resulted in a dramatic reduction in wear, probably due to the reduction in the corrosion-wear interactions between the tribological pair. PMID:18491698

Figueiredo-Pina, C G; Yan, Y; Neville, A; Fisher, J



Mediterranean Ocean Colour Chlorophyll trend  

NASA Astrophysics Data System (ADS)

Monitoring chlorophyll (Chl) concentration, seen as a proxy for phytoplankton biomass, is an efficient tool in order to understand the response of marine ecosystem to human pressures. This is particularly important along the coastal regions, in which the strong anthropization and the irrational exploitation of resources represent a persistent threat to the biodiversity. The aim of this work is to assess the effectiveness and feasibility of using Ocean Color (OC) data to monitor the environmental changes in Mediterranean Sea and to develop a method for detecting trend from OC data that can constitute a new indicator of the water quality within the EU Marine Strategy Framework Directive implementation. In this study the Mediterranean merged Case1-Case2 chlorophyll product, produced by CNR-ISAC and distributed in the framework of MyOcean, is analyzed. This product is obtained by using two different bio-optical algorithms for open ocean (Case1) and coastal turbid (Case2) waters; this improves the quality of the Chl satellite estimates, especially near the coast. In order to verify the real capability of the this product for estimating Chl trend and for selecting the most appropriated statistical test to detect trend in the Mediterranean Sea, a comparison between OC and in situ data are carried out. In-situ Chl data are part of the European Environment Information and Observation Network (Eionet) of the European Environmental Agency (EEA). Four different statistical approaches to estimate trend have been selected and used to compare trend values obtained with in-situ and OC data. Results show that the best agreement between in-situ and OC trend is achieved using the Mann- Kendall test. The Mediterranean trend map obtained applying this test to the de-seasonalized OC time series shows that, in accordance with the results of many authors, the case 1 waters of Mediterranean sea are characterized by a negative trend. However, the most intense trend signals, both negative and positive, are found in case 2 waters in correspondence of the river deltas. These trend signals are frequently linked to the implementation or non-implementation of the legislation introduced to control the nutrient discharge into the sea from European rivers.

rinaldi, eleonora; colella, simone; santoleri, rosalia



Male courtship preferences demonstrate discrimination against allopatric colour morphs in a cichlid fish.  


Whether premating isolation is achieved by male-specific, female-specific or sex-independent assortative preferences often depends on the underlying evolutionary processes. Here we test mate preferences of males presented with females of different allopatric colour variants of the cichlid fish Tropheus sp., a Lake Tanganyika endemic with rich geographical colour pattern variation, in which the strength of sexual isolation varies between populations. We conducted two-way mate choice experiments to compare behaviour of males of a red-bodied morph (population Moliro) towards females from their own population with behaviour towards females from four allopatric populations at different stages of phylogenetic and phenotypic divergence. Males courted same-population females significantly more intensely than females of other populations, and reduced their heteromorphic courtship efforts both with increasing genetic and increasing phenotypic distinctness of the females. In particular, females of a closely related red-bodied population received significantly more courtship than either genetically distinct, similarly coloured females ('Kirschfleck' morph) or genetically related, differently coloured females ('yellow-blotch' morph), both of which were courted similarly. Genetically and phenotypically distinct females (Tropheus polli) were not courted at all. Consistent with previous female-choice experiments, female courtship activity also decreased with increasing genetic distance from the males' population. Given successful experimental and natural introgression between colour morphs and the pervasive allopatry of related variants, we consider it unlikely that assortative preferences of both sexes were driven by direct selection during periods of secondary contact or, in turn, drove colour pattern differentiation in allopatry. Rather, we suggest that sexual isolation evolved as by-product of allopatric divergence. PMID:23405907

Zoppoth, P; Koblmüller, S; Sefc, K M



Effects of forest edges, fruit display size, and fruit colour on bird seed dispersal in a New Zealand mistletoe, Alepis flavida  

Microsoft Academic Search

This study examined how forest edges, fruit display size, and fruit colour influenced rates of seed dispersal in an endemic, bird-dispersed, New Zealand mistletoe species, Alepis flavida. To examine rates of seed dispersal, fruit removal rates were compared between plants growing on forest edges and in forest interior, and also between two morphs of plants with different coloured fruits. Two

Catherine E. Bach; Dave Kelly


The influence of different amplitudes of Total Solar Irradiance changes on the Medieval climate in coupled model simulations  

NASA Astrophysics Data System (ADS)

The climate of Medieval times (950-1250 AD) has been investigated with a set of simulations using the comprehensive ECHO-G AOGCM. To test the influence of changes in external solar forcing two simulations with different amplitudes of the variations in solar activity have been carried out, the first one assuming a 0.35 ‰ difference between the Late Maunder Minimum and present day, and the second one assuming only half of this change. All simulations are forced with changes in orbital and greenhouse gas forcing, but the reference simulation is carried out with constant solar forcing. The evolution of modelled Northern hemispheric summer near-surface temperatures shows a significant (alpha=0.05) anomaly indicating higher temperatures of around +0.2 K (+0.1 K) for the high-amplitude (low amplitude) simulation over the period 1100 -1300 AD compared to the reference simulation. Temperatures on the northern hemispheric scale therefore respond linearly on the amplitude of solar activity changes. The control simulation, forced without any changes in external solar activity, shows no increased temperature levels during the entire medieval period. The spatially resolved temperature anomaly patterns show largest temperature anomalies over continental areas, with maximum values around +0.5 K over the interiors of the Northern hemispheric continents during the entire Medieval period. For smaller spatial scales, for instance Scandinavia, the forced simulations show no such clear-cut positive temperature signals because the ratio between signal and internal variability is reduced. For the North Atlantic region the internal variability is mostly affected by the variability related to the NAO and the North Atlantic drift. Compared to the reference simulation the summer NAO shows in both simulations a negative phase during the entire medieval period, mostly pronounced within the high-amplitude solar forcing simulation. The North Atlantic SST anomaly pattern also shows a response to the different amplitudes, indirectly related to the NAO pattern, with pronounced negative SST anomalies south of Greenland in the low-amplitude simulation versus a dipole pattern with moderately reduced SSTs in higher latitudes and positive SSTs in the subtropical Atlantic in the high-amplitude simulation, the latter most likely induced via direct solar insolation forcing. Our results suggest that alongside changes in internal variability, a driving factor of climate variability on multi-decadal time and on continental-to-hemispheric scales is likely related to changes in solar activity. To test the robustness of these results obtained with the ECHO-G model more simulations with different climate models and/or different scalings and reconstructions of the solar activity are needed including a higher resolved stratosphere in order to account for potential interactive ozone changes.

Wagner, S.; Zorita, E.; Gonzalez-Rouco, F. J.



A novel method for testing the veridicality of dental colour assessments.  


The Commission Internationale de l'Eclairage (CIE) L*a*b* three-dimensional coordinates suggest strong correlations between the data of a* (red-green axis) and b* (blue-yellow axis), as both are located on the same plane in the model and should therefore show a strong dependency. In order to assess the veridicality of colour determinations, the null hypothesis of no significant changes in CIE-a*/b* coherences of dental colours following a colour or lightness change induced by external dental bleaching was tested. Values from 231 extracted anterior teeth were assessed using the digital photographic CIELAB recalculation method. Teeth were then assigned to three groups (n = 77) with contrasting baseline CIE-L* values. Group A served as the control with no alteration in dental colour. The specimens in the two other groups were altered in colour or lightness employing treatment with either 15 per cent carbamide peroxide (group B) or 38 per cent hydrogen peroxide (group C). Pearson's pairwise correlation coefficient of CIE-L*; a*, CIE-L*; b*, and CIE-a*; b* were calculated for assessments at baseline (T0) and after 2 (T1), 4 (T2), 12 (T3), and 24 (T4) weeks. The correlations of a* and b* from T0 to T4, in relation to group A, were stable, with coefficients of 0.78?0.65?0.65?0.69?0.67. Bleaching-induced colour and lightness changes did not have a significant influence on the a*/b* coherences assessed. A distinctly weaker and inverse relationship was observed between L* and a* values and between L* and b* values in the groups, with correlation coefficients ranging from -0.54 to -0.12. Colour coherences detected at specific points in time were in agreement with theoretical CIE colour coherences. In order to compare the methodology of different colour analyses, the analysis of correlations between CIE-a* and -b* values is advocated as an additional routine test in future CIELAB studies. PMID:21289016

Knösel, Michael; Reus, Monika; Rosenberger, Albert; Ziebolz, Dirk



Sexual selection based on egg colour: physiological models and egg discrimination experiments in a cavity-nesting bird  

Microsoft Academic Search

It has been proposed that the blue-green bird egg colourations of many avian species may constitute a sexually selected female\\u000a signal that males can use to modulate their parental investment. A fundamental untested assumption for the validation of this\\u000a hypothesis is that males can accurately assess differences in the colour of eggs. A recent review suggests that this could\\u000a be

Jesús M. Avilés; Juan J. Soler; Nathan S. Hart


Evidence of post-pollination barriers among three colour morphs of the deceptive orchid Dactylorhiza sambucina (L.) Soó  

Microsoft Academic Search

Floral-colour polymorphism in rewardless orchids has been hypothesized to be maintained by means of naïve insects, which after\\u000a visiting a flower without reward will tend to fly elsewhere, looking for a flower of a different colour. In this study, levels\\u000a of male and female reproductive success were monitored in Southern Italy populations of the deceptive orchid Dactylorhiza sambucina, through field

Giuseppe Pellegrino; Francesca Bellusci; Aldo Musacchio



A mutation in the MATP gene causes the cream coat colour in the horse.  


In horses, basic colours such as bay or chestnut may be partially diluted to buckskin and palomino, or extremely diluted to cream, a nearly white colour with pink skin and blue eyes. This dilution is expected to be controlled by one gene and we used both candidate gene and positional cloning strategies to identify the "cream mutation". A horse panel including reference colours was established and typed for different markers within or in the neighbourhood of two candidate genes. Our data suggest that the causal mutation, a G to A transition, is localised in exon 2 of the MATP gene leading to an aspartic acid to asparagine substitution in the encoded protein. This conserved mutation was also described in mice and humans, but not in medaka. PMID:12605854

Mariat, Denis; Taourit, Sead; Guérin, Gérard



Suckling kid breed and slaughter weight discrimination using muscle colour and visible reflectance.  


Meat colour was evaluated in 141 male suckling kids from five Spanish breeds: Blanca Andaluza (BA), Blanca Celtibérica (BC), Moncaína (MO), Negra Serrana-Castiza (NE) and Pirenaica (PI). Kids were slaughtered at 7.5 and 11.5 kg. pH and colour were measured in the longissimus thoracis et lumborum muscle. pH values did not differ significantly among breeds. Lightness tended to decrease and redness to increase as weight increased. BC and NE at light weight and BC and BA at heavy weight were characterized by greater lightness, chroma and hue. At both weights MO and PI were darker and showed lower values for chroma and hue. BA at light weight and NE at heavy weight were characterized by values that were between those of the former groups for all variables. Discriminant analysis based on colour and pH correctly classified 48.9% of the kids into their breed and slaughter weight. PMID:21041040

Ripoll, G; Alcalde, M J; Horcada, A; Panea, B



Effects of moderate abundance changes on the atmospheric structure and colours of Mira variables  

NASA Astrophysics Data System (ADS)

Aims: We study the effects of moderate deviations from solar abundances upon the atmospheric structure and colours of typical Mira variables. Methods: We present two model series of dynamical opacity-sampling models of Mira variables which have (1) 1/3 solar metallicity; and (2) "mild" S-type C/O abundance ratio ([C/O] = 0.9) with typical Zr enhancement (solar +1.0). These series are compared to a previously studied solar-abundance series which has similar fundamental parameters (mass, luminosity, period, radius) that are close to those of o Cet. Results: Both series show noticeable effects of abundance upon stratifications and infrared colours but cycle-to-cycle differences mask these effects at most pulsation phases, with the exception of a narrow-water-filter colour near minimum phase.

Scholz, M.; Ireland, M. J.; Wood, P. R.



Differences between the wear couples metal-on-polyethylene and ceramic-on-ceramic in the stability against dislocation of total hip replacement  

Microsoft Academic Search

After total hip replacement an insufficient range of motion (ROM) can lead to contact between femoral neck and rim of the cup (=impingement) causing dislocation and consecutive material failure. The purpose of this study was to analyse the influence of different wear couples on the ROM and stability against dislocation. By means of a special testing device the ROM until

Rainer Bader; Erwin Steinhauser; Susanne Zimmermann; Wolfram Mittelmeier; Roger Scholz; Raymonde Busch



Comparison of total tract digestibility and nitrogen balance between Cinta Senese and Large White pigs fed on different levels of dietary crude protein  

Microsoft Academic Search

The work aimed to study the digestive capacity and nitrogen balance of Cinta Senese pig fed diets with different crude protein (CP) content. Twelve castrated male pigs (6 Cinta Senese and 6 Large White), of the same body weight (on average 62.7kg), were submitted to 8 subsequent trials of total tract digestibility and nitrogen balance. The pigs were kept in

A. Acciaioli; F. Sirtori; L. Pianaccioli; G. Campodoni; C. Pugliese; R. Bozzi; O. Franci



Colour control and selectivity in TiAlN solar-thermal absorbers  

NASA Astrophysics Data System (ADS)

Optical constants for simulations were obtained by R- and T-measurements on TiAlN thin films deposited on Corning 7059 glass. The model parameterized free carrier effects and an inter-band excitation. The calculations demonstrated that the colour effects are due to interference and inter-band absorption around 500 nm in a single layer coating. The peak shifts with the thickness of the thin film which gives a simple way to obtain different colours. Solar absorptance of 86 % can be reached already for a single TiAlN-film on an Al substrate.

Zhao, Shuxi; Zhu, Dechun; Ribbing, Carl-G.



OCoc-from Ocean Colour to Organic Carbon  

NASA Astrophysics Data System (ADS)

The terrigenous carbon export into the Arctic shelf systems is a major component of the Arctic Organic Carbon (OC) cycle. Mac Guire et al.(2009)in their review on the Arctic Carbon Cycle recommendate to strengthen observations and design the research sector of 'scaling' that is a key challenge to link the processes observed and understood on fine scales to larger scales, e.g., needed for modeling. Here, remote sensing observations can become important tools. Recent development of satellite ocean color sensors such as MODIS, SeaWiFS, MERIS has been accompanied by an increased effort to establish Ocean Colour (OC) algorithms (e.g., for chlorophyll, suspended matter, coloured dissolved organic matter). The ‘OCoc-from Ocean Colour to Organic Carbon’ project (IPY-project 1176), funded by the German Research Foundation (DFG), is an Ocean Colour study joined with the Arctic Coastal Dynamics ACD network and Arctic Circum-polar Coastal Observatory Network ACCO-Net (IPY-project 90). OCoc uses MERIS data for synoptical monitoring of terrigenous suspended and organic matter in the late-summer ice-free waters of the Laptev See region. MERIS Reduced Resolution (RR)-LIB data are processed towards optical aquatic parameters using Beam-Visat4.2 and the MERIS Case2 Regional processor for coastal application (C2R). Calculated aquatic parameters are optical coefficients and calculated concentrations of chlorophyll, total suspended matter and coloured dissolved organic matter absorption from the water leaving reflectances. The Laptev Sea is characterized by a very shallow topography and considerable Regions of Fresh water Influence ROFIs. The maximum river discharge of the Lena River, the second largest Arctic river in terms of annual fresh water discharge happens during the spring ice-breakup in June. Fluvial systems serve as point sources for high fluxes of dissolved and particulate terrigenous materials. The Laptev Sea coast is a highly dynamic mainly sedimentary ice-rich system that delivers vast amounts of interstorage carbon and old carbon from syncryogenic deposits. Initial comparisons with expedition data (cDOM, transparency, SPM, turbidity, chlorophyll) from the German-Russian TRANSDRIFT expeditions and from German-Russian expeditions at the Laptev Sea Coast (2008 to 2010) are presented. MERIS-C2R optical parameters such as the first attenuation depth, ’Z90’, seem adequately to represent true conditions. Whereas the derived concentration parameters seem to be overestimated. The synoptic information of the optical MERIS-C2R parameters offers an immediate wealth of information. The spatial patterns of the processed MERIS C2R time series show the inter-annual scale of the atmospherically driven circulation patterns. On event scales, we need to investigate if weather patterns potentially contribute to short pulses and circulation patterns.

Heim, B.; Doerffer, R.; Overduin, P. P.; Lantuit, H.; Hoelemann, J. A.; Kassens, H.; Wegner, C.



Pulmonary rehabilitation after total laryngectomy: a randomized cross-over clinical trial comparing two different heat and moisture exchangers (HMEs).  


Post-laryngectomy heat and moisture exchanger (HME) use is known to have a beneficial effect on tracheal climate, pulmonary symptoms and related aspects. This study aims to investigate differences in clinical effects between the first and second generation Provox HMEs. The second generation (Provox XtraHME) has better humidification properties than the first generation (Provox HME), and has been shown to further improve tracheal climate. Forty-five laryngectomized patients, who were already using an HME, participated in a prospective, randomized cross-over clinical study in which each HME was used for 6 weeks. Results showed that for most parameters studied, the second generation HME performed equally well or better than the first generation HME. The improvement in tracheal climate translated into patients reporting significantly less tracheal dryness with the second generation than with the first generation (p = 0.039). Using an HME with better humidification properties is related to a reduction in tracheal dryness in our study population. PMID:23595617

Herranz, Jesús; Espiño, María Alvarez; Morado, Carolina Ogen



Raman spectroscopy of coloured resins used in antiquity: dragon's blood and related substances  

Microsoft Academic Search

Dragon's blood is a deep red resin which has been used for centuries by many cultures and much prized for it's rarity, depth of colour and alchemical associations. The original source of dragon's blood resin is believed to be Dracaena cinnabari from Socotra in Africa, but since mediaeval times there have been several alternatives from different geographical locations from the

Howell G. M. Edward; Luiz Fernando C. de Oliveira; Anita Quye



Cognitive Representation of Colour in Bilinguals: The Case of Greek Blues  

ERIC Educational Resources Information Center

A number of recent studies demonstrate that bilinguals with languages that differ in grammatical and lexical categories may shift their cognitive representation of those categories towards that of monolingual speakers of their second language. The current paper extended that investigation to the domain of colour in Greek-English bilinguals with…

Athanasopoulos, Panos



Habitat light, colour variation, and ultraviolet reflectance in the Grand Cayman anole, Anolis conspersus  

Microsoft Academic Search

Data from a diversity of sources are consistent with the hypothesis that the Grand Cayman anole,Anolis conspersus , is descended directly from Anolis grahami of Jamaica. Although the two species have remained morphologically similar, coloration in A. conspersus has changed considerably from that of its ancestor. The most dramatic difference is seen in dewlap colour, where A. conspersus has evolved



Wildfire-ash: Relationships between colour, water repellency and organic carbon content  

Microsoft Academic Search

During a forest fire, a layer of vegetative ash is often deposited over soil surface. The amount of ash deposited as well as its physical and chemical properties are highly variable. These parameters are influenced particularly by vegetation type and fire severity, resulting in a differing ash colour. This ash remains over the soil until it is redistributed by water

M. B. Bodí; J. Mataix-Solera; S. H. Doerr; A. Cerdà



Lack of response to background colour in Pieris brassicae pupae reared on carotenoid-free diet  

Microsoft Academic Search

THE Large White butterfly (Pieris brassicae L.) is a toxic species1, aposematic at all stages of its life-cycle. Probably for this reason, the pupa responds to the colour of its background in a somewhat different manner from that of many other Pierid species, displaying heterochromy (background contrasting) rather than homochromy (background matching). In this respect, there is some genetical variation