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Influence of different maceration time and temperatures on total phenols, colour and sensory properties of Cabernet Sauvignon wines.  


Maceration and fermentation time and temperatures are important factors affecting wine quality. In this study different maceration times (3 and 6 days) and temperatures (15? and 25?) during production of red wine (Vitis vinifera L. Cabernet Sauvignon) were investigated. In all wines standard wine chemical parameters and some specific parameters as total phenols, tartaric esters, total flavonols and colour parameters (CD, CI, T, dA%, %Y, %R, %B, CIELAB values) were determined. Sensory evaluation was performed by descriptive sensory analysis. The results demonstrated not only the importance of skin contact time and temperature during maceration but also the effects of transition temperatures (different maceration and fermentation temperatures) on wine quality as a whole. The results of sensory descriptive analyses revealed that the temperature significantly affected the aroma and flavour attributes of wines. The highest scores for 'cassis', 'clove', 'fresh fruity' and 'rose' characters were obtained in wines produced at low temperature (15?) of maceration (6 days) and fermentation. PMID:23703104

?ener, Hasan; Yildirim, Hatice Kalkan



Geometric algebra colour image representations and derived total orderings for morphological operators Part I: Colour quaternions  

E-print Network

Geometric algebra colour image representations and derived total orderings for morphological is the first part of a series of studies which focus on defining colour total orderings based on geometric algebra represen- tations of colour images. In particular, in this article we focus on real quaternions



Distribution and photobiology of Symbiodinium types in different light environments for three colour morphs of the coral Madracis pharensis: is there more to it than total irradiance?  

NASA Astrophysics Data System (ADS)

The role of symbiont variation in the photobiology of reef corals was addressed by investigating the links among symbiont genetic diversity, function and ecological distribution in a single host species, Madracis pharensis. Symbiont distribution was studied for two depths (10 and 25 m), two different light habitats (exposed and shaded) and three host colour morphs (brown, purple and green). Two Symbiodinium genotypes were present, as defined by nuclear internal transcribed spacer 2 ribosomal DNA (ITS2-rDNA) variation. Symbiont distribution was depth- and colour morph-dependent. Type B15 occurred predominantly on the deeper reef and in green and purple colonies, while type B7 was present in shallow environments and brown colonies. Different light microhabitats at fixed depths had no effect on symbiont presence. This ecological distribution suggests that symbiont presence is potentially driven by light spectral niches. A reciprocal depth transplantation experiment indicated steady symbiont populations under environment change. Functional parameters such as pigment composition, chlorophyll a fluorescence and cell densities were measured for 25 m and included in multivariate analyses. Most functional variation was explained by two photobiological assemblages that relate to either symbiont identity or light microhabitat, suggesting adaptation and acclimation, respectively. Type B15 occurs with lower cell densities and larger sizes, higher cellular pigment concentrations and higher peridinin to chlorophyll a ratio than type B7. Type B7 relates to a larger xanthophyll-pool size. These unambiguous differences between symbionts can explain their distributional patterns, with type B15 being potentially more adapted to darker or deeper environments than B7. Symbiont cell size may play a central role in the adaptation of coral holobionts to the deeper reef. The existence of functional differences between B-types shows that the clade classification does not necessarily correspond to functional identity. This study supports the use of ITS2 as an ecological and functionally meaningful marker in Symbiodinium.

Frade, P. R.; Englebert, N.; Faria, J.; Visser, P. M.; Bak, R. P. M.



Quantifying Plant Colour and Colour Difference as Perceived by Humans Using Digital Images  

PubMed Central

Human perception of plant leaf and flower colour can influence species management. Colour and colour contrast may influence the detectability of invasive or rare species during surveys. Quantitative, repeatable measures of plant colour are required for comparison across studies and generalisation across species. We present a standard method for measuring plant leaf and flower colour traits using images taken with digital cameras. We demonstrate the method by quantifying the colour of and colour difference between the flowers of eleven grassland species near Falls Creek, Australia, as part of an invasive species detection experiment. The reliability of the method was tested by measuring the leaf colour of five residential garden shrub species in Ballarat, Australia using five different types of digital camera. Flowers and leaves had overlapping but distinct colour distributions. Calculated colour differences corresponded well with qualitative comparisons. Estimates of proportional cover of yellow flowers identified using colour measurements correlated well with estimates obtained by measuring and counting individual flowers. Digital SLR and mirrorless cameras were superior to phone cameras and point-and-shoot cameras for producing reliable measurements, particularly under variable lighting conditions. The analysis of digital images taken with digital cameras is a practicable method for quantifying plant flower and leaf colour in the field or lab. Quantitative, repeatable measurements allow for comparisons between species and generalisations across species and studies. This allows plant colour to be related to human perception and preferences and, ultimately, species management. PMID:23977275

Kendal, Dave; Hauser, Cindy E.; Garrard, Georgia E.; Jellinek, Sacha; Giljohann, Katherine M.; Moore, Joslin L.



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



Testing the AUDI2000 colour-difference formula for solid colours using some visual datasets with usefulness to automotive industry  

NASA Astrophysics Data System (ADS)

Colour-difference formulas are tools employed in colour industries for objective pass/fail decisions of manufactured products. These objective decisions are based on instrumental colour measurements which must reliably predict the subjective colour-difference evaluations performed by observers' panels. In a previous paper we have tested the performance of different colour-difference formulas using the datasets employed at the development of the last CIErecommended colour-difference formula CIEDE2000, and we found that the AUDI2000 colour-difference formula for solid (homogeneous) colours performed reasonably well, despite the colour pairs in these datasets were not similar to those typically employed in the automotive industry (CIE Publication x038:2013, 465-469). Here we have tested again AUDI2000 together with 11 advanced colour-difference formulas (CIELUV, CIELAB, CMC, BFD, CIE94, CIEDE2000, CAM02-UCS, CAM02-SCD, DIN99d, DIN99b, OSA-GP-Euclidean) for three visual datasets we may consider particularly useful to the automotive industry because of different reasons: 1) 828 metallic colour pairs used to develop the highly reliable RIT-DuPont dataset (Color Res. Appl. 35, 274-283, 2010); 2) printed samples conforming 893 colour pairs with threshold colour differences (J. Opt. Soc. Am. A 29, 883-891, 2012); 3) 150 colour pairs in a tolerance dataset proposed by AUDI. To measure the relative merits of the different tested colour-difference formulas, we employed the STRESS index (J. Opt. Soc. Am. A 24, 1823-1829, 2007), assuming a 95% confidence level. For datasets 1) and 2), AUDI2000 was in the group of the best colour-difference formulas with no significant differences with respect to CIE94, CIEDE2000, CAM02-UCS, DIN99b and DIN99d formulas. For dataset 3) AUDI2000 provided the best results, being statistically significantly better than all other tested colour-difference formulas.

Martínez-García, Juan; Melgosa, Manuel; Gómez-Robledo, Luis; Li, Changjun; Huang, Min; Liu, Haoxue; Cui, Guihua; Luo, M. Ronnier; Dauser, Thomas



Antioxidant capacity, total phenolics, glucosinolates and colour parameters of rapeseed cultivars.  


The antioxidant capacity of twenty nine rapeseed varieties was determined by using ferric reducing antioxidant power (FRAP) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) methods. Mean FRAP (3190-6326?mol Trolox/100g) and DPPH (3194-6346?mol Trolox/100g) values for methanolic extracts of rapeseed cultivars did not differ significantly. Moreover, the total content of phenolics (756-1324mg sinapic acid/100g), glucosinolates (4.2-87.5?mol/g, respectively), erucic acid (0.0-56.1%) and colour parameters of the studied rapeseed cultivars were analysed. Antioxidant capacity determined by FRAP and DPPH methods correlated significantly with total phenolic content (TPC) in rapeseed cultivars (r=0.9332, 0.9339, p<0.001). Also, significant, inverse correlations were found between antioxidant capacity, total phenolics and luminosity (L(?)) or red colour intensity (a(?)) of rapeseed cultivars. Principal component analysis (PCA) allowed the rapeseed varieties to be differentiated based on their antioxidant capacities, total amounts of phenolics, glucosinolates, erucic acid and colour parameters. PMID:23140700

Szyd?owska-Czerniak, Aleksandra; Bartkowiak-Broda, Iwona; Karlovi?, Igor; Karlovits, György; Sz?yk, Edward



Marked colour divergence in the gliding membranes of a tropical lizard mirrors population differences in the colour of falling leaves.  


Populations of the Bornean gliding lizard, Draco cornutus, differ markedly in the colour of their gliding membranes. They also differ in local vegetation type (mangrove forest versus lowland rainforest) and consequently, the colour of falling leaves (red and brown/black in mangrove versus green, brown and black in rainforest). We show that the gliding membranes of these lizards closely match the colours of freshly fallen leaves in the local habitat as they appear to the visual system of birds (their probable predators). Furthermore, gliding membranes more closely resembled colours of local fallen leaves than standing foliage or fallen leaves in the other population's habitat. This suggests that the two populations have diverged in gliding membrane coloration to match the colours of their local falling leaves, and that mimicking falling leaves is an adaptation that functions to reduce predation by birds. PMID:25540157

Klomp, D A; Stuart-Fox, D; Das, I; Ord, T J



Is there a different preference in the choice of background colour between melanistic and cryptically coloured morphs of the adder, Vipera berus?  

Microsoft Academic Search

Most natural populations of the adder (Vipera berus), including both cryptically coloured (zig?zag) and melanistic (black) individuals, are polymorphic in dorsal colour pattern. In this study we report experiments to test whether a difference in preference of background colour exists between these morphs. The occurrence of this difference between colour morphs was studied in (1) indoor and outdoor enclosures, (2)

Massimo Capula; Luca Luiselli



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

PubMed Central

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.



Do we only dream in colour? A comparison of reported dream colour in younger and older adults with different experiences of black and white media  

Microsoft Academic Search

This study aimed to find out whether differences in the reported colour of dreams can be attributed to the influence of black and white media or to methodological issues. Two age groups, with different media experience, were compared on questionnaire and diary measures of dream colour. Analysis revealed that people who had access to black and white media before colour

Eva Murzyn



Cyclic colour change in the bearded dragon Pogona vitticeps under different photoperiods.  


The ability to change colour rapidly is widespread among ectotherms and has various functions including camouflage, communication and thermoregulation. The process of colour change can occur as an aperiodic event or be rhythmic, induced by cyclic environmental factors or regulated by internal oscillators. Despite the importance of colour change in reptile ecology, few studies have investigated the occurrence of a circadian rhythm in lizard pigmentation. Additionally, although colour change also entails changes in near-infrared reflectance, which may affect thermoregulation, little research has examined this part of the spectrum. We tested whether the bearded dragon lizard, Pogona vitticeps, displays an endogenous circadian rhythm in pigmentation changes that could be entrained by light/dark (LD) cycles and how light affected the relative change in reflectance in both ultraviolet-visible and near-infrared spectra. We subjected 11 lizards to four photoperiodic regimens: LD 12:12; LD 6:18; LD 18:6 and DD; and measured their dorsal skin reflectance at 3-hour intervals for 72 hours after a habituation period. A proportion of lizards displayed a significant rhythm under constant darkness, with maximum reflectance occurring in the subjective night. This endogenous rhythm synchronised to the different artificial LD cycles, with maximum reflectance occurring during dark phases, but did not vary in amplitude. In addition, the total ultraviolet-visible reflectance in relation to the total near-infrared reflectance was significantly higher during dark phases than during light phases. We conclude that P. vitticeps exhibits a circadian pigmentation rhythm of constant amplitude, regulated by internal oscillators and that can be entrained by light/dark cycles. PMID:25354192

Fan, Marie; Stuart-Fox, Devi; Cadena, Viviana



Interference and holography with femtosecond laser pulses of different colours.  


Interferometry and holography are two domains that are based on observation and recording of interference fringes from two light beams. While the aim of the first technique is to reveal and map the phase difference of two wave fronts, the main task of the second technique is to reconstruct one of the two recording waves via diffraction of the other wave from the recorded fringe pattern (hologram). To create fringes, mutually coherent waves from the same laser are commonly used. It is shown here that fringes can be observed and holograms can be recorded with ultrashort, sub-picosecond pulses even of different colour, generated in our experiment with two parametric amplifiers seeded, both by the same mode-locked Ti-sapphire laser. The appearance of permanent and transient gratings is confirmed by recording of an image-bearing hologram, by observation of two-beam coupling gain in a pump-probe experiment and by frequency conversion in Raman-Nath self-diffraction from a moving grating. PMID:25651807

Odoulov, Serguey; Shumelyuk, Alexandr; Badorreck, Holger; Nolte, Stefan; Voit, Kay-Michael; Imlau, Mirco



Bees associate colour cues with differences in pollen rewards.  


In contrast to the wealth of knowledge concerning sucrose-rewarded learning, the question of whether bees learn when they collect pollen from flowers has been little addressed. The nutritional value of pollen varies considerably between species, and it may be that bees learn the features of flowers that produce pollen best suited to the dietary requirements of their larvae. It is still unknown, however, whether a non-ingestive reward pathway for pollen learning exists, and how foraging bees sense differences between pollen types. Here we adopt a novel experimental approach testing the learning ability of bees with pollen rewards. Bumblebees were reared under controlled laboratory conditions. To establish which pollen rewards are distinguishable, individual bees were given the choice of collecting two types of pollen, diluted to varying degrees with indigestible ?-cellulose. Bees preferentially collected a particular pollen type, but this was not always the most concentrated sample. Preferences were influenced by the degree of similarity between samples and also by the period of exposure, with bees more readily collecting samples of lower pollen concentration after five trials. When trained differentially, bees were able to associate an initially less-preferred contextual colour with the more concentrated sample, whilst their pollen preferences did not change. Successful learning of contextual cues seems to maintain pollen foraging preferences over repeated exposures, suggesting that fast learning of floral cues may preclude continuous sampling and evaluation of alternative reward sources, leading to constancy in pollen foraging. PMID:24855678

Nicholls, Elizabeth; de Ibarra, Natalie Hempel



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



Kinetics of colour change of kiwifruits during hot air and microwave drying  

Microsoft Academic Search

The kinetics of colour changes of kiwifruits, due to drying by hot air, microwave (MW) and hot air–MW finish drying, were studied. Kinetic parameters for the colour change were determined using Hunter L-, a-, b-values, chroma, Hue, total colour difference and browning index (BI) values. The drying process changed all three colour parameters (L, a, b), causing a colour shift

Medeni Maskan



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.



Cryptic differences in colour among Müllerian mimics: how can the visual capacities of predators and prey shape the evolution of wing colours?  


Antagonistic interactions between predators and prey often lead to co-evolution. In the case of toxic prey, aposematic colours act as warning signals for predators and play a protective role. Evolutionary convergence in colour patterns among toxic prey evolves due to positive density-dependent selection and the benefits of mutual resemblance in spreading the mortality cost of educating predators over a larger prey assemblage. Comimetic species evolve highly similar colour patterns, but such convergence may interfere with intraspecific signalling and recognition in the prey community, especially for species involved in polymorphic mimicry. Using spectrophotometry measures, we investigated the variation in wing coloration among comimetic butterflies from distantly related lineages. We focused on seven morphs of the polymorphic species Heliconius numata and the seven corresponding comimetic species from the genus Melinaea. Significant differences in the yellow, orange and black patches of the wing were detected between genera. Perceptions of these cryptic differences by bird and butterfly observers were then estimated using models of animal vision based on physiological data. Our results showed that the most strikingly perceived differences were obtained for the contrast of yellow against a black background. The capacity to discriminate between comimetic genera based on this colour contrast was also evaluated to be higher for butterflies than for birds, suggesting that this variation in colour, likely undetectable to birds, might be used by butterflies for distinguishing mating partners without losing the benefits of mimicry. The evolution of wing colour in mimetic butterflies might thus be shaped by the opposite selective pressures exerted by predation and species recognition. PMID:24444083

Llaurens, V; Joron, M; Théry, M



Colour stability of acrylic resin denture teeth after immersion in different beverages.  


The colour stability of acrylic resin denture teeth in beverages was investigated. A spectrophotometer measured the colour (CIE-L*a*b* system) of all specimens after storage in distilled water/for 24 h at 37 degrees C (T0). Specimens were then immersed in various beverages. After 15 days (T1) and 30 days (T2), for each material, the mean deltaE values were calculated and compared by two-way ANOVA and Tukey intervals (alpha = 0.05). In the deltaT0T1 period, specimens stored in red wine were significantly discoloured, compared to distilled water (P = 0.003). There was no difference between immersion solutions in deltaET0T2 (P = 0.772) and in deltaET1T2 (P = 0.058), and no difference between materials in all immersion periods. PMID:25134362

Arana-Correa, B E; Sepúlveda-Navarro, W F; Florez, F L E; Urban, V M; Jorge, J H; Campanha, N H



Should a water colour parameter be included in lake total phosphorus prediction models used for the Water Framework Directive?  


Under the Water Framework Directive (WFD) lakes are classified according to a variety of criteria. This classification facilitates state of the environment assessments and helps identify work needed to achieve the objectives of the WFD, which are broadly to maintain and/or restore water quality and ecological status at a level recognised as good or high. To achieve high or good status, lakes must meet a criterion for total phosphorus (TP) that is linked to a predicted reference condition value that is derived by various models. Lakes which fail to meet good status may require expensive remedial actions to be undertaken, thus accurate identification of the reference condition TP concentration is vital for effective environmental management. However, the models currently employed could be improved for some regions, particularly those with carbon rich soils. By examining 19 reference condition lakes (i.e. lakes essentially non-impacted by humans) in peaty areas of Scotland, we found that a simple parameter linked to water colour and humic substances was a better predictor of TP than the currently employed models (R(2) 0.585 vs R(2) < 0.01). Therefore, for Scotland and elsewhere, in regions with carbon rich soils and lakes with humic waters the TP predictive models could be improved by development and incorporation of a parameter related to water colour and humic components. PMID:25262390

Vinogradoff, Susan I; Oliver, Ian W



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



Planetary nebula or symbiotic Mira? Near infrared colours mark the difference  

E-print Network

Nebulae around symbiotic Miras look very much like genuine planetary nebulae, although they are formed in a slightly different way. We present near infrared photometry of known and suspected symbiotic nebulae obtained with the Deep Near Infrared Southern Sky Survey (DENIS). We demonstrate that the near infrared colours are an excellent tool to distinguish symbiotic from genuine planetary nebulae. In particular we find that the bipolar planetary nebulae M 2-9 and Mz 3 are in fact symbiotic Miras. Further observations on prototype symbiotic Miras prove that the proposed classification scheme works generally.

S. Schmeja; S. Kimeswenger



Synaesthesia and colour constancy.  


Grapheme-colour synaesthesia is an atypical condition characterized by the perception of colours when reading achromatic text. We investigated the level of colour processing responsible for these experiences. To do so, we tapped a central characteristic of colour perception. In different lighting conditions the same wavelength of light can prompt the perception of different colours. This helps humans recognize distinctive coloured objects despite changes in illumination. We wanted to see if synaesthetic colours were generated at a neural locus that was susceptible to colour constancy analyses. We used colour matching and naming tasks to examine interactions between simulated coloured illuminants and synaesthetic colours. Neither synaesthetic colour matching or naming was impacted. This contrasted with non-synaesthetic control participants, who performed the colour-matching task with graphemes physically coloured to mimic synaesthesia. Our data suggest that synaesthetic colour signals are not generated at lower-levels of colour processing, but are introduced at higher levels of analysis and are therefore not impacted by the processes responsible for perceptual constancy. PMID:22487049

Erskine, Holly; Mattingley, Jason B; Arnold, Derek H



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. PMID:24158142

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



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


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. PMID:24158142

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



Coloured oil droplets enhance colour discrimination.  


The eyes of most diurnal reptiles and birds contain coloured retinal filters-oil droplets. Although these filters are widespread, their adaptive advantage remains uncertain. To understand why coloured oil droplets appeared and were retained during evolution, I consider both the benefits and the costs of light filtering in the retina. Oil droplets decrease cone quantum catch and reduce the overlap in sensitivity between spectrally adjacent cones. The reduction of spectral overlap increases the volume occupied by object colours in a cone space, whereas the decrease in quantum catch increases noise, and thus reduces the discriminability of similar colours. The trade-off between these two effects determines the total benefit of oil droplets. Calculations show that coloured oil droplets increase the number of object colours that can be discriminated, and thus are beneficial for colour vision. PMID:12816638

Vorobyev, Misha



Cryptic differences in colour among Mullerian mimics: how can the visual capacities of predators and prey shape the evolution  

E-print Network

the variation in wing coloration among comimetic butterflies from distantly related lineages. We focused of the wing were detected between genera. Perceptions of these cryptic differences by bird and butterfly evaluated to be higher for butterflies than for birds, suggesting that this variation in colour, likely unde


Colour Reflection Holography  

NASA Astrophysics Data System (ADS)

Available from UMI in association with The British Library. Requires signed TDF. The fidelity of colour reproduction achievable in reflection holograms is analysed by an in depth experimental and theoretical treatment. The experimental work consists of a comparison of materials and development of techniques for producing colour reflection holograms. Colour reflection holograms were recorded using a suitable material and various types of three-band laser illumination. Holograms recorded with the combinations 458, 529, and 633 nm or 458, 529, and 647 nm reproduced a full range of colours accurately, including yellow, dark blue, and purple images, which was impossible by previous methods. A theoretical model of the colour reproduction by holograms incorporates colour rendering analysis, effects of bandwidth, a new definition of signal to noise ratio, wavelength shifting, and colour balance. The model compares octagons formed by points on a CIE diagram corresponding to eight Munsell coloured chips when reproduced by the holographic image and when illuminated by a standard light source. Figures of merit of average vector length between image and object colours and gamut area size are considered. The theory compares well with holograms recorded of the Munsell chips using eight different sets of recording wavelengths. Holographic image colour reproduction for all possible recording wavelengths is predicted by the model. From this analysis, optimum wavelength combinations are obtained that support experimental results. In conclusion, a new definition of true colour holography is suggested that considers the quality of colour reproduction of a holographic image compared to colours viewed under normal conditions.

Hubel, Paul Matthew



The Tooth and Skin Colour Interrelationship across the Different Ethnic Groups  

PubMed Central

Objectives. The purpose of the study was to investigate the relation between skin and tooth colour parameters in various ethnic groups. Materials and Methods. Saudi Arabian, Indian, African, and East Asian ethnic groups of 75 each were included in the study. The tooth colour was determined by spectrophotometer in CIELAB parameters. The skin colour was measured at earlobe, forehead, and malar locations by clinical skin photography. The data was statistically analysed by one-way ANOVA and correlation tests. Results. The “L” vale for the Saudi Arabian group had a strong correlation at earlobe location (r = 0.275), while correlation was found at forehead (r = 0.271) and malar region (r = 0.261) with Indian ethnic group. A strong negative correlation was observed in African ethnic group at all three locations for “L” parameter. The redness value “a” is found to have strong negative linear correlation between the earlobe and tooth for Saudi Arabian (r = ?0.240) and Indian ethnic groups (r = ?0.268). The “b” showed no correlation with skin location in all groups except positive correlation in African ethnic groups. Conclusions. The strong correlation was found between the skin and tooth colour parameters; hence the skin colour can be used as a guide for artificial tooth selection in edentulous patients. PMID:25101125

Haralur, Satheesh B.; Dibas, Ahmed Mohammed; Almelhi, Nabil Abdullah; Al-Qahtani, Dhafer Ali



Colour and antioxidant capacity stability in grape, strawberry and plum peel model juices at different pHs and temperatures.  


The aim of the study was to evaluate the anthocyanin sources potential as natural food colouring. Model juices (MJs) of grape, strawberry and plum peel were stored during 8weeks in darkness at 6 and 23°C. The colour stability was evaluated at pH 2.4, 3.1, 4.0, 5.0, 6.0, 7.0 and 8.1, and the antioxidant capacity at pH 4.0. The plum peel MJ showed the best and more stable colour parameters. The grape MJs presented a high stability although the chroma values were very low. The storage of strawberry MJ demonstrated a low stability at 23°C. The vitamin C equivalent antioxidant capacity in grape, strawberry and plum peel MJs was 7, 40 and 50mg/L, respectively. The strawberry MJ stability was very low. Total phenolics and anthocyanins ranged between 18-101 and 2-62mg/L of MJ, respectively. The determination coefficient was R(2)=0.745 between the antioxidant capacity and total phenolics. PMID:24518333

Hernández-Herrero, J A; Frutos, M J



Is colour cognitive?  

NASA Astrophysics Data System (ADS)

In recent years, colour-vision abilities have been rather generously ascribed to various invertebrates and even bacteria. This uncertainty of when to diagnose colour vision stems in part from confusing what colour vision can do with what it is. What colour vision can do is discriminate wavelength independent of intensity. However, if we take this as a definition of what colour vision is, then we might be obliged to conclude that some plants and bacteria have colour vision. Moreover, there is a similar confusion of what are necessary and what are sufficient mechanisms and behavioural abilities for colour vision. To humans, seeing in colour means seeing an image in which objects/lights have chromatic attributes—in contrast to the sensation that we have when viewing monochrome movies, or our experience in dim light when only rod vision is possible. The necessary basic equipment for this is to have at least two types of photoreceptors that differ in spectral sensitivity, and at least one type of spectrally opponent cell to compare the signals from the photoreceptors. Clearly, however, a necessary additional prerequisite for colour vision is to have vision, which entails the identification of shapes, sizes and locations of objects in the world. Thus, if an animal has colour vision, it should see an image in which distinct objects/lights have colour attributes. This distinguishes colour vision from wavelength discrimination, but also from what has historically been called wavelength-specific behaviour: a type of behaviour triggered by fixed configurations of spectral receptor signals; however, we discuss difficulties in diagnosing wavelength-specific behaviour as an indicator of the absence of colour vision. Finally, we discuss whether colour vision, by definition, contains a cognitive dimension for ordering and classifying perceptual experience.

Skorupski, Peter; Chittka, Lars



A comparison of the carotenoid accumulation in Capsicum varieties that show different ripening colours: deletion of the capsanthin-capsorubin synthase gene is not a prerequisite for the formation of a yellow pepper  

Microsoft Academic Search

Ripe pepper (Capsicum sp.) fruits can display a range of colours from white to deep red. To un- derstand better the regulatory mechanisms of the carotenoid biosynthetic pathways that underlie these ripening colours, Capsicum varieties that show seven different fully ripe colour types were analysed. The levels and composition of the carotenoid accumulation in these samples at different stages of

Sun-Hwa Ha; Jung-Bong Kim; Jong-Sug Park; Shin-Woo Lee; Kang-Jin Cho



Daily behaviour can differ between colour morphs of the same species: a study on circadian activity behaviour of grey and pied zebra finches.  


To investigate if the plumage colour mutation relates to circadian activity behaviour in the zebra finch, Taeniopygia guttata, wild type grey and pied mutant males were sequentially subjected for three weeks each to 12 h light:12 h darkness (12L:12D) and constant dim light (LL(dim)) condition. During the first 3 h of the 12 h day, pied finches were significantly greater active than grey finches. Also, as compared to grey, pied finches had longer activity duration in the day, with early activity onsets and late activity offsets. This was changed under free-running condition (LL(dim)), when the activity later in the subjective day (clock hour 9 and 11) was significantly greater in grey than in pied finches.Two colour morphs differed in daily activity profile, but not in the total daily activity or circadian rhythm period. Results suggest that greyzebra finches represent late chronotype, and could perhaps be better adapted to a seemingly stressful environment, such as low intensity LL(dim) in the present study. PMID:24851415

Mishra, Ila; Trivedi, Amit Kumar; Kumar, Vinod



Evaluation of colour stability of provisional restorative materials exposed to different mouth rinses at varying time intervals: an in vitro study.  


The most important factor affecting esthetics is colour. Whether a definitive prosthesis or a provisional restoration, maintenance of esthetics is of prime concern along with restoration of function. Colour stability of provisional prosthesis is affected by various factors and various studies are documented in the literature on this. The purpose of this study was to evaluate the colour stability of provisional restorative materials exposed to different mouth rinses at varying time intervals. 120 discs, each of self cure tooth moulding material, Protemp 4 and Revotek LC were prepared and immersed in two mouth rinses, hexidine and periogard and evaluated for their colour stability after 1 week, 1 and 3 months. The data obtained was statistically analysed using ANOVA and Tukey's post hoc analysis. The results indicate that there is a significant difference in the colour variation of various materials in two different mouth rinses at different time intervals. Revotek LC was found to be the most colour stable material and periogard had the least staining potential at varying time intervals. PMID:24605003

Prasad, D Krishna; Alva, Harshitha; Shetty, Manoj



Effect of artificial ageing using different wood chips on the antioxidant activity, resveratrol and catechin concentration, sensory properties and colour of two Greek red wines.  


Two Greek red wines (Syrah and Cabernet) were artificially aged with different wood chips (white oak, red oak, Turkey oak, chestnut, Bosnian pine, cherry, common juniper, common walnut, white mulberry, black locust and apricot). The influence of each wood species was tested for up to 20 days. The optimum duration for the extraction of total polyphenols was 20 days (Syrah) or 10 days (Cabernet) when chips of white oak, chestnut, cherry, white mulberry, black locust and apricot where used. Resveratrol and catechin concentrations ranged within the limits previously reported in literature. A high antioxidant activity was established after 10 days of artificial ageing. The sensory evaluation showed that the best results were produced by the apricot chips after 5 days (Syrah) or black locust and apricot after 5 days (Cabernet). Colour was seen to increase with both time of ageing and number of wood chips added. PMID:23871038

Gortzi, Olga; Metaxa, Xenia; Mantanis, George; Lalas, Stavros



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.


Unconventional colour vision.  


Butterflies and stomatopods are certainly outliers in their unconventional colour sense and despite some similarities at first glance, in fact sample the world of colour very differently. In one way, butterflies are relatively conventional, possessing either tri-or tetrachromatic colour vision, then just adding one or several task-specific sub-mechanisms onto this. It is the stomatopods so far that have really pushed the boat out into a different colour vision mechanism. Over 400 million years of independent evolution they have arrived at a solution with more in common with the way a satellite sensor examines the colours of the earth than other animals. Remember, however, that unconventional colour vision is not just the realm of the serially polychromatic. Apparently waterfleas with four classes of spectral receptors living in ponds operate a task-specific spectral sense with no need, or indeed neural processing power, to construct a complex discriminatory mechanism. It seems they have the butterfly added-extra set without the more complex comparative chromatic mechanisms, although in truth, conclusive behavioural proof is lacking. Behavioural observation of colour vision in the ecological context of each animal is vital before making the distinction between conventional and unconventional. Just counting spectral sensitivities is never enough. PMID:25514002

Marshall, Justin; Arikawa, Kentaro



Colour and carotenoid changes of pasteurised orange juice during storage.  


The correlation of carotenoid changes with colour degradation of pasteurised single strength orange juice was investigated at 20, 28, 35 and 42°C for a total of 32 weeks of storage. Changes in colour were assessed using the CIELAB system and were kinetically described by a zero-order model. L(?), a(?), b(?), ?E(?), Cab(?) and hab were significantly changed during storage (p<0.05). Activation energies for all colour parameters were 64-73 kJ mol(-1). Several carotenoids showed important changes and appeared to have different susceptibilities to storage. A decrease of ?-cryptoxanthin was observed at higher temperatures, whereas antheraxanthin started to decrease at lower temperatures. Depending on the time and temperature, changes in carotenoids could be due to isomerisation reactions, which may lead to a perceptible colour change. Although the contribution of carotenoids was recognised to some extent, other reactions seem of major importance for colour degradation of orange juice during storage. PMID:25308677

Wibowo, Scheling; Vervoort, Liesbeth; Tomic, Jovana; Santiago, Jihan Santanina; Lemmens, Lien; Panozzo, Agnese; Grauwet, Tara; Hendrickx, Marc; Van Loey, Ann



Colour measurements of surfaces to evaluate the restoration materials  

NASA Astrophysics Data System (ADS)

In this paper two case studies on the application of colour measurements for the evaluation of some restoration materials are discussed. The materials related to the research are: watercolours employed in restoration of wall paintings and preservative/consolidants for wood artifacts. Commercial watercolours, supplied by Maimeri, Windsor&Newton and Talens factories have been tested. Colour measurements have been performed by means of a reflectance spectrophotometer (RS) before and after accelerated ageing of watercolours at 92% relative humidity (RH) and in a Solar Box chamber. The experimental results show that watercolours based on natural earths and artificial ultramarine undergo the main colour changes, expressed as L*, a* and b* variations and total colour difference (?E*). In the other cases colour differences depend on both watercolour typology and suppliers. The other example concerns the evaluation of colour change due to surface treatment of Poplar (Populus sp.) and chestnut (Castanea sativa L.) wood samples. The wooden samples have been treated with a novel organic preservative/consolidant product that has been tested also in a real case as comparison. The treated samples have been artificially aged in Solar Box chamber equipped with a 280 nm UV filter. Colour has been measured before and after the artificial ageing by means of a RS. Colour changes have been determined also for the main door of an historical mansion in Viterbo, made of chestnut wood, and exposed outdoors.

Lo Monaco, Angela; Marabelli, Maurizio; Pelosi, Claudia; Picchio, Rodolfo



Same trait, different receiver response: unlike females, male American goldfinches do not signal status with bill colour  

E-print Network

ornamentation genetic correlation social competition Spinus tristis status signal In species in which both sexes that carotenoid-based bill colour of female American goldfinches, Spinus tristis, functions as a signal of status

Murphy, Troy G.


Sex Differences in Obesity Associated with Total Fertility Rate  

PubMed Central

The identification of biological and ecological factors that contribute to obesity may help in combating the spreading obesity crisis. Sex differences in obesity rates are particularly poorly understood. Here we show that the strong female bias in obesity in many countries is associated with high total fertility rate, which is well known to be correlated with factors such as low average income, infant mortality and female education. We also document effects of reduced access to contraception and increased inequality of income among households on obesity rates. These results are consistent with studies that implicate reproduction as a risk factor for obesity in women and that suggest the effects of reproduction interact with socioeconomic and educational factors. We discuss our results in the light of recent research in dietary ecology and the suggestion that insulin resistance during pregnancy is due to historic adaptation to protect the developing foetus during famine. Increased access to contraception and education in countries with high total fertility rate might have the additional benefit of reducing the rates of obesity in women. PMID:20485682

Brooks, Robert; Maklakov, Alexei



Colour and urban landscape  

Microsoft Academic Search

Colour regards urban landscape of important elements, it can reflect a city's history, local features and cultural tradition. This paper discusses to colour aesthetic application in urban landscape design, namely how to play a landscape of natural colour and artificial colour features and create urban landscape beauty of colours. Keywords-colour; urban landscape; urban colour \\

Xueping Wu; Shicheng Xu



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. PMID:21829462

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



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



The colours of the Sun  

E-print Network

We compile a sample of Sun-like stars with accurate effective temperatures, metallicities and colours (from the UV to the near-IR). A crucial improvement is that the effective temperature scale of the stars has recently been established as both accurate and precise through direct measurement of angular diameters obtained with stellar interferometers. We fit the colours as a function of effective temperature and metallicity, and derive colour estimates for the Sun in the Johnson/Cousins, Tycho, Stromgren, 2MASS and SDSS photometric systems. For (B-V)_Sun, we favour the ``red'' colour 0.64 versus the ``blue'' colour 0.62 of other recent papers, but both values are consistent within the errors; we ascribe the difference to the selection of Sun-like stars versus interpolation of wider colour-Teff-metallicity relations.

Johan Holmberg; Chris Flynn; Laura Portinari



Hsp70 and lipid peroxide levels following heat stress in Xeropicta derbentina (Krynicki 1836) (Gastropoda, Pulmonata) with regard to different colour morphs.  


Terrestrial snails which live under dry and hot conditions need efficient mechanisms of adaptation to counteract the problems of desiccation and over-heating. A profoundly heat tolerant snail species is the Mediterranean Xeropicta derbentina, exhibiting different shell colour morphs ranging from pale white to darkly banded. Considering that dark-pigmented snails are believed to have a disadvantage due to faster heating, we investigated possible differences in the stress markers Hsp70 and lipid peroxideation between four pre-defined colour morphs which were exposed to different temperatures for eight hours. The highest Hsp70 levels were observed in response to 38-40 °C. Levels decreased when this temperature was exceeded. Snails of a pre-defined colour category 3 (with a large black band at the umbilicus side of the shell) showed the most prominent Hsp70 response. Lipid peroxideation levels also showed a maximum at 38 °C but displayed a second peak at rather high temperatures at which the Hsp70 level already had decreased (45-48 °C). Particularly pure white snails (category 1) and the most pigmented ones (category 4) were found to have different levels of lipid peroxidation at 38 °C and 45 °C compared to the other morphs. A hypothesis involving a combined two-phase defence mechanism, to which both, the Hsp70 protection system and the antioxidant defence system, may contribute, is discussed. PMID:25108358

Dieterich, A; Troschinski, S; Schwarz, S; Di Lellis, M A; Henneberg, A; Fischbach, U; Ludwig, M; Gärtner, U; Triebskorn, R; Köhler, H-R



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.



Segmentation of Colour Layers in Historical Maps Based on Hierarchical Colour Sampling  

NASA Astrophysics Data System (ADS)

A colour image segmentation (CIS) process for scanned historical maps is presented to overcome common problems associated with segmentation of old documents such as (1) variation in colour values of the same colour layer within one map page, (2) differences in typical colour values between homogeneous areas and thin line-work, which belong both to the same colour layer, and (3) extensive parameterization that results in a lack of robustness. The described approach is based on a two-stage colour layer prototype search using a constrained sampling design. Global colour layer prototypes for the identification of homogeneous regions are derived based on colour similarity to the most extreme colour layer values identified in the map page. These global colour layer prototypes are continuously adjusted using relative distances between prototype positions in colour space until a reliable sample is collected. Based on this sample colour layer seeds and directly connected neighbors of the same colour layer are determined resulting in the extraction of homogeneous colour layer regions. In the next step the global colour layer prototypes are recomputed using a new sample of colour values along the margins of identified homogeneous coloured regions. This sampling step derives representative prototypes of map layer sections that deviate significantly from homogeneous regions of the same layers due to bleaching, mixed or false colouring and ageing of the original scanned documents. A spatial expansion process uses these adjusted prototypes as start criterion to assign the remaining colour layer parts. The approach shows high robustness for map documents that suffer from low graphical quality indicating some potential for general applicability due to its simplicity and the limited need for preliminary information. The only input required is the colours and number of colour layers present in the map.

Leyk, Stefan


The handicap of abnormal colour vision.  


All people with abnormal colour vision, except for a few mildly affected deuteranomals, report that they experience problems with colour in everyday life and at work. Contemporary society presents them with increasing problems because colour is now so widely used in printed materials and in computer displays. Equal opportunity law gives them protection against unfair discrimination in employment, so a decision to exclude a person from employment on the grounds of abnormal colour vision must now be well supported by good evidence and sound argument. This paper reviews the investigations that have contributed to understanding the nature and consequences of the problems they have. All those with abnormal colour vision are at a disadvantage with comparative colour tasks that involve precise matching of colours or discrimination of fine colour differences either because of their loss of colour discrimination or anomalous perception of metamers. The majority have problems when colour is used to code information, in man-made colour codes and in naturally occurring colour codes that signal ripeness of fruit, freshness of meat or illness. They can be denied the benefit of colour to mark out objects and organise complex visual displays. They may be unreliable when a colour name is used as an identifier. They are slower and less successful in search when colour is an attribute of the target object or is used to organise the visual display. Because those with the more severe forms of abnormal colour vision perceive a very limited gamut of colours, they are at a disadvantage in the pursuit and appreciation of those forms of art that use colour. PMID:15312030

Cole, Barry L



An RGB Approach to Prismatic Colours  

ERIC Educational Resources Information Center

Teaching prismatic colours usually boils down to establishing the take-home message that white light consists of "differently refrangible" coloured rays. This approach explains the classical spectrum of seven colours but has its limitations, e.g. in discussing spectra from setups with higher resolution or in understanding the well…

Theilmann, Florian; Grusche, Sascha



Molecular Characterisation of Colour Formation in the Prawn Fenneropenaeus merguiensis  

PubMed Central

Introduction Body colouration in animals can have a range of functions, with predator protection an important aspect of colour in crustaceans. Colour determination is associated with the carotenoid astaxanthin, which is taken up through the diet and stabilised in the tissues by the protein crustacyanin. As a variety of genes are found to play a role in colour formation in other systems, a holistic approach was employed in this study to determine the factors involved in Fenneropenaeus merguiensis colouration. Results Full length F. merguiensis crustacyanin subunit A and C sequences were isolated. Crustacyanin subunit A and C were found in the F. merguiensis transcriptomes of the muscle/cuticle tissue, hepatopancreas, eye stalk and nervous system, using 454 next generation sequencing technology. Custom microarray analysis of albino, light and dark F. merguiensis cuticle tissue showed genes encoding actin, sarcoplasmic calcium-binding protein and arginine kinase to be 4-fold or greater differentially expressed (p<0.05) and down-regulated in albinos when compared to light and dark samples. QPCR expression analysis of crustacyanin and total astaxanthin pigment extraction revealed significantly (p<0.05) lower crustacyanin subunit A and C gene transcript copy numbers and total astaxanthin levels in albinos than in the light and dark samples. Additionally, crustacyanin subunit A and C expression levels correlated positively with each other. Conclusions This study identified gene products putatively involved in crustacean colouration, such as crustacyanin, sarcoplasmic calcium-binding protein and forms of actin, and investigated differences in gene expression and astaxanthin levels between albino, light and dark coloured prawns. These genes open a path to enhance our understanding of the biology and regulation of colour formation. PMID:23441225

Ertl, Nicole G.; Elizur, Abigail; Brooks, Peter; Kuballa, Anna V.; Anderson, Trevor A.; Knibb, Wayne R.



Hemispherical total emissivity of Hastelloy N with different surface conditions  

NASA Astrophysics Data System (ADS)

The hemispherical total emissivity of Hastelloy N (a candidate structural material for Next Generation Nuclear Plants (NGNPs), particularly for the molten fluoride cooled reactors) was measured using an experimental set-up that was constructed in accordance with the standard ASTM C835-06. The material surface conditions included: (i) 'as received' (original) sample from the supplier; (ii) samples with increased surface roughness through sand blasting; (iii) oxidized surface, and (iv) samples coated with graphite powder. The emissivity of the as received samples varied from around 0.22 to 0.28 in the temperature range of 473 K to 1498 K. The emissivity increased when the roughness of the surface increased compared to an as received sample. When Hastelloy N was oxidized in air at 1153 K or coated with graphite powder, its emissivity increased substantially. The sample sand blasted with 60 grit beads and sprinkled with graphite powder showed an increase of emissivity from 0.2 to 0.60 at 473 K and from 0.25 to 0.67 at 1473 K. The oxidized surface showed a similar behavior: an increase in emissivity compared to an unoxidized sample. This increase in emissivity has strong favorable safety implications in terms of decay heat removal in post-accident environments. The data were compared with another Hastelloy family member, Hastelloy X.

Gordon, Andrew J.; Walton, Kyle L.; Ghosh, Tushar K.; Loyalka, Sudarshan K.; Viswanath, Dabir S.; Tompson, Robert V.



Colour Guided Colour Image Steganography  

E-print Network

Information security has become a cause of concern because of the electronic eavesdropping. Capacity, robustness and invisibility are important parameters in information hiding and are quite difficult to achieve in a single algorithm. This paper proposes a novel steganography technique for digital color image which achieves the purported targets. The professed methodology employs a complete random scheme for pixel selection and embedding of data. Of the three colour channels (Red, Green, Blue) in a given colour image, the least two significant bits of any one of the channels of the color image is used to channelize the embedding capacity of the remaining two channels. We have devised three approaches to achieve various levels of our desired targets. In the first approach, Red is the default guide but it results in localization of MSE in the remaining two channels, which makes it slightly vulnerable. In the second approach, user gets the liberty to select the guiding channel (Red, Green or Blue) to guide the r...

Amirtharajan, R; Swarup, Motamarri Abhilash; K, Mohamed Ashfaaq; Rayappan, John Bosco Balaguru



Minimizing unsatisfaction in colourful neighbourhoods  

NASA Astrophysics Data System (ADS)

Colouring sparse graphs under various restrictions is a theoretical problem of significant practical relevance. Here we consider the problem of maximizing the number of different colours available at the nodes and their neighbourhoods, given a predetermined number of colours. In the analytical framework of a tree approximation, carried out at both zero and finite temperatures, solutions obtained by population dynamics give rise to estimates of the threshold connectivity for the incomplete to complete transition, which are consistent with those of existing algorithms. The nature of the transition as well as the validity of the tree approximation are investigated.

Wong, K. Y. Michael; Saad, David



The colour wheels of art, perception, science and physiology  

NASA Astrophysics Data System (ADS)

Colour is not the domain of any one discipline be it art, philosophy, psychology or science. Each discipline has its own colour wheel and this presentation examines the origins and philosophies behind the colour circles of Art, Perception, Science and Physiology (after image) with reference to Aristotle, Robert Boyle, Leonardo da Vinci, Goethe, Ewald Hering and Albert Munsell. The paper analyses and discusses the differences between the four colour wheels using the Natural Colour System® notation as the reference for hue (the position of colours within each of the colour wheels). Examination of the colour wheels shows the dominance of blue in the wheels of art, science and physiology particularly at the expense of green. This paper does not consider the three-dimensionality of colour space its goal was to review the hue of a colour with regard to its position on the respective colour wheels.

Harkness, Nick



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



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



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 in insect thermoregulation: empirical and theoretical tests in the colour-changing grasshopper, Kosciuscola tristis.  


Body colours can result in different internal body temperatures, but evidence for the biological significance of colour-induced temperature differences is inconsistent. We investigated the relationship between body colour and temperature in a model insect species that rapidly changes colour. We used an empirical approach and constructed a heat budget model to quantify whether a colour change from black to turquoise has a role in thermoregulation for the chameleon grasshopper (Kosciuscola tristis). Our study shows that colour change in K. tristis provides relatively small temperature differences that vary greatly with wind speed (0.55 °C at ms(-1) to 0.05 °C at 10 ms(-1)). The biological significance of this difference is unclear and we discuss the requirement for more studies that directly test hypotheses regarding the fitness effects of colour in manipulating body temperature. PMID:23108152

Umbers, K D L; Herberstein, M E; Madin, J S



RESEARCH ARTICLE Open Access Differences in gait characteristics between total hip,  

E-print Network

RESEARCH ARTICLE Open Access Differences in gait characteristics between total hip, knee, and ankle arthroplasty (THA), total knee arthroplasty (TKA) and total ankle arthroplasty (TAA) with a group of healthy side-to-side asymmetries in gait characteristics. Keywords: Gait, Arthroplasty, Hip, Knee, Ankle

Boyer, Edmond



EPA Science Inventory

Total organic carbon (TOC) and dissolved organic carbon (DOC) have long been used to estimate the amount of natural organic matter (NOM) found in raw and finished drinking water. In recent years, computer automation and improved instrumental analysis technologies have created a ...


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. PMID:23573156

Ramanauskien?, Kristina; Ink?nien?, Asta Marija; Petrikait?, Vilma; Briedis, Vitalis



What weta want: colour preferences of a frugivorous insect  

Microsoft Academic Search

Plants use colours as signals to attract mutualists and repel antagonists. Fleshy-fruits are often conspicuously coloured\\u000a to signal different types of information including fruit maturity and spatial location. Previous work on fruit colour selection\\u000a focus on large diurnal vertebrates, yet fruit colours are perceived differently by frugivores with different types of visual\\u000a systems. Here, we tested whether a nocturnal, frugivorous,

Nik Fadzly; K. C. Burns



Whorfian effects on colour memory are not reliable.  


The Whorfian hypothesis suggests that differences between languages cause differences in cognitive processes. Support for this idea comes from studies that find that patterns of colour memory errors made by speakers of different languages align with differences in colour lexicons. The current study provides a large-scale investigation of the relationship between colour language and colour memory, adopting a cross-linguistic and developmental approach. Colour memory on a delayed matching-to-sample (XAB) task was investigated in 2 language groups with differing colour lexicons, for 3 developmental stages and 2 regions of colour space. Analyses used a Bayesian technique to provide simultaneous assessment of two competing hypotheses (H1-Whorfian effect present, H0-Whorfian effect absent). Results of the analyses consistently favoured H0. The findings suggest that Whorfian effects on colour memory are not reliable and that the importance of such effects should not be overestimated. PMID:25230782

Wright, Oliver; Davies, Ian R L; Franklin, Anna



Does Colour Preference Have a Role in Colour Term Acquisition?  

ERIC Educational Resources Information Center

A developmental association exists between colour preference and emerging colour term acquisition in young children. Colour preference might influence colour term acquisition by directing attention towards or away from a particular colour, making it more or less memorable. To investigate the role that colour preference may have in the acquisition…

Pitchford, Nicola J.; Davis, Emma E.; Scerif, Gaia



Total Factor Productivity, Human Capital, and Outward Orientation: Differences by Stage of Development and Geographic Regions  

E-print Network

Total Factor Productivity, Human Capital, and Outward Orientation: Differences by Stage 2002 Abstract: Do openness and human capital accumulation promote economic growth? While intuition factor productivity that include, among many others, human capital, openness, and distortion of domestic

Ahmad, Sajjad


Posterior cruciate ligament-retaining and posterior-stabilized total knee arthroplasty: differences in surgical technique  

PubMed Central

Summary The debate over the relative merits of substituting or retaining the posterior cruciate ligament in total knee arthroplasty is still ongoing. This article discusses the differences between the two procedures, considering the biomechanics and the surgical techniques involved.

D’Anchise, Roberto; Andreata, Mauro; Balbino, Cristiana; Manta, Nicola



Colour polymorphism in birds: causes and functions  

Microsoft Academic Search

We studied polymorphism in all species of birds that are presently known to show intraspecific variation in plumage colour. At least three main mecha- nisms have been put forward to explain the maintenance of polymorphism: apostatic, disruptive and sexual selection. All of them make partly different predictions. Our aims were to investigate evolutionary causes and adaptive functions of colour polymorphism

P. Galeotti; D. Rubolini; P. O. Dunn; M. Fasola



Colour Measurements and Modeling  

NASA Astrophysics Data System (ADS)

The most common property to measure quality of any material is its appearance. Appearance includes colour, shape, size and surface conditions. The analysis of colour is especially an important consideration when determining the efficacy of variety of postharvest treatments. Consumers can easily be influenced by preconceived ideas of how a particular fruit or vegetable or a processed food should appear, and marketers often attempt to improve upon what nature has painted. Recently colour measurements have also been used as quality parameters and indicator of some inner constituents of the material. In spite of the significance of colour in food industries, many continue to analyze it inadequately. This chapter deals with theory of colour, colour scales and its measurement, sampling techniques, and modeling of colour values for correlating them with some internal quality parameters of selected fruits.

Jha, Shyam N.


Colour Appearance and Colour Rendering of HDR Scenes: An Experiment  

Microsoft Academic Search

In order to gain a deeper understanding of the appearance of coloured objects in a three-dimensional scene, the research introduces a multidisciplinary experimental approach. The experiment employed two identical 3-D Mondrians, which were viewed and compared side by side. Each scene was subjected to different lighting conditions. First, we used an illumination cube to diffuse the light and illuminate all

Carinna Parraman; Alessandro Rizzi; John J. McCannc


Contrast normalization in colour vision: the effect of luminance contrast on colour contrast detection  

PubMed Central

While contrast normalization is well known to occur in luminance vision between overlaid achromatic contrasts, and in colour vision between overlaid colour contrasts, it is unknown whether it transfers between colour and luminance contrast. Here we investigate whether contrast detection in colour vision can be normalized by achromatic contrast, or whether this is a selective process driven only by colour contrast. We use a method of cross-orientation masking, in which colour detection is masked by cross-oriented achromatic contrast, over a range of spatio-temporal frequencies (0.375–1.5?cpd, 2–8?Hz). We find that there is virtually no cross-masking of colour by achromatic contrast under monocular or binocular conditions for any of the spatio-temporal frequencies tested, although we find significant facilitation at low spatio-temporal conditions (0.375?cpd, 2?Hz). These results indicate that the process of contrast nornalization is colour selective and independent of achromatic contrast, and imply segregated chromatic signals in early visual processing. Under dichoptic conditions, however, we find a strikingly different result with significant masking of colour by achromatic contrast. This indicates that the dichoptic site of suppression is unselective, responding similarly to colour and luminance contrast, and suggests that dichoptic suppression has a different origin from monocular or binocular suppression. PMID:25491564

Mullen, Kathy T.; Kim, Yeon Jin; Gheiratmand, Mina



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



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



An Interaction of Screen Colour and Lesson Task in CAL  

ERIC Educational Resources Information Center

Colour is a common feature in computer-aided learning (CAL), though the instructional effects of screen colour are not well understood. This investigation considers the effects of different CAL study tasks with feedback on posttest performance and on posttest memory of the lesson colour scheme. Graduate students (n=68) completed a computer-based…

Clariana, Roy B.



Use of Descartes Folium Equation for Deriving a Relation between Total Aperture of Fractures after Uniaxial Compression and Strain Parameters of Different Rocks Exhibiting Negative Total Volumetric Strains  

NASA Astrophysics Data System (ADS)

The axial, crack and total volumetric strains, porosity, elastic constants, crack damage stresses, uniaxial compressive strengths, as well as fracture apertures and number of fracture traces in rock samples surface after compression were defined for different chalk, basalt, dolomite, granite, limestone and sandstone samples exhibiting negative total volumetric strain at failure. It is established that the total (summed) aperture of vertical fractures obtained on the lateral surface of rock sample is related to three characteristic strain parameters: axial strain at the onset of negative total volumetric strain, axial failure strain and negative total volumetric strain at failure. The relation is based on Descartes folium equation, where the length of the loop of folium is equal to axial strain coordinate at the onset of negative total volumetric strain. This relation shows that the total aperture increases according to power law with increasing difference between axial failure strain and axial strain at the onset of negative total volumetric strain. Simultaneously, an increase in this difference leads to an increase in the value of negative total volumetric strain at failure. It is found that a direct correlation between total aperture of fractures and negative total volumetric strain at failure is relatively weak. Nevertheless, total aperture of fractures tends to increase with increasing absolute value of negative total volumetric strain at failure. It is revealed that there is no connection between the number of fracture traces and negative total volumetric strain at failure.

Palchik, V.



Colour and chemical changes of the lime wood surface due to CO2 laser thermal modification  

NASA Astrophysics Data System (ADS)

We studied colour and main wood components changes of lime wood caused by CO2 laser beam irradiation. The dry surface of lime wood (Tilia vulgaris L.) was irradiated with the CO2 laser beam (wavelength of 10.6 ?m) at different exposures (expressed as the irradiation dose). Colour changes were monitored by the spectrophotometer, chemical changes were observed by the ATR-FTIR spectroscopy and carbohydrates were analysed by the HPLC method. With the growth of the irradiation dose (from 8.1 to 28.7 J cm-2) lightness (?L*) decrease and increase of the total colour difference (?E*) were observed. Higher values of the input energy lead to accelerating the mutual reaction of the functional groups resulting in the subsequent condensation of lignin. The total decrease in saccharides at the highest irradiation dose reaches 27.39% of the initial amount of saccharides in the reference sample. We have observed degradation and loss of hemicelluloses.

Kubovský, Ivan; Ka?ík, František



Brand Guidelines Colour version  

E-print Network

Brand Guidelines Overview May 2012 #12;Colour version Shield alone Black Colour reverse Colour reverse on red Reverse Brand Overview 1.2 The Signature Our signature system is comprised of two elements and Reverse require special version of the shield, available upon request. #12;1x ¼x ¼x ¼x ¼x ¼x¼x Brand

Shoubridge, Eric


Colourful FKS subtraction  

E-print Network

I formulate in a colour-friendly way the FKS method for the computation of QCD cross sections at the next-to-leading order accuracy. This is achieved through the definition of subtraction terms for squared matrix elements, constructed with single colour-dressed or pairs of colour-ordered amplitudes. The latter approach relies on the use of colour flows, is exact to all orders in $N$, and is thus particularly suited to being organized as a systematic expansion in 1/N.

Stefano Frixione



Robert Grosseteste's colours  

E-print Network

Here I am proposing a translation and discussion of the De Colore, one of the short scientific treatises written by Robert Grosseteste. In this very short treatise of the mid-1220s, Grosseteste continued the discussion on light and colours he started in the De Iride. He describes two manners of counting colours: one gives an infinity of tones, the other counts seven colours. In both cases, colours are created by the purity or impurity of the transparent medium when light is passing through it. This medieval framework survived until Newton's experiments with prisms.

Sparavigna, Amelia Carolina




EPA Science Inventory

Model stream chronic dosing studies (42 d) were conducted with three total dissolved solids (TDS) recipes. The recipes differed in composition of major ions. Community scale emergence was compared with single-species responses conducted simultaneously using the whole effluent tox...


Long-term outcome of low contact stress total knee arthroplasty with different mobile bearing designs  

PubMed Central

Purpose to evaluate the differences in clinical outcome and survivorship of three different mobile bearings for total knee arthroplasty. Methods a retrospective study was conducted in 60 patients (53 females, 7 males, mean age: 68 years and 5 months) each submitted to total knee replacement using one of the three different mobile bearings of the LCS system (Depuy Johnson & Johnson, Warsaw, IN). The diagnosis was knee osteoarthritis in 57 cases and rheumatoid arthritis in three cases. Three different groups of 20 cases each were identified: total knee arthroplasties with mobile menisci (group 1); total knee arthroplasties with the rotating platform (group 2); and total knee arthroplasties with the anteroposterior glide platform (group 3). As regards the component fixation, 33 implants were cementless, three were cemented, and in 24 only the tibial component was cemented. The patella was not replaced. Results although the duration of follow-up differed between the three groups, the clinical and radiological results at final follow-up showed no revision of femoral and/or tibial components for mechanical or septic reasons, and no signs of impending failure. One meniscal bearing, showing polyethylene wear after 17 years, was successfully replaced. Conclusions the present retrospective study confirmed the long-term effectiveness of knee implants with mobile bearings, in which the congruity of the surfaces makes it possible to overcome the problem of high contact stresses that may result in polyethylene wear and osteolysis; at the same time, these implants eliminate constraint forces thereby reducing the risk of mechanical loosening. Level of evidence Level III, retrospective comparative study. PMID:25606553




Neutron absolute and total cross section difference measurements in the mass-140 region  

NASA Astrophysics Data System (ADS)

We have used a 100-MeV electron linac and neutron time-of-flight facility to measure precise neutron total cross sections in the mass-140 region for incident neutron energies of 3-60 MeV. We measured the absolute neutron total cross section of 140Ce and the total cross section differences of 139La-140Ce, 141Pr-140Ce, and 142Ce-140Ce. These cross section differences oscillate with energy. Optical model calculations have been performed which fit the 140Ce total cross section well over the 3-60 MeV energy region. The 139La-140Ce and 141Pr-140Ce difference data were satisfactorily fit by small changes in the geometrical parameters of the potential. The 142Ce-140Ce data could not be fit by small changes in the geometry of the potential and we found that the changes required to achieve a satisfactory fit suggest that 142Ce is either nonspherical or more easily deformed than 140Ce. Using our final optical model parameters we calculated ?(r2)=A-140 for the real part of the potential. The 139La-140Ce and 141Pr-140Ce optical model values of ?(r2) were in agreement with corresponding ?(r2)q values calculated using muonic x-ray data. The value for 142Ce-140Ce was not.

Camarda, H. S.; Phillips, T. W.; White, R. M.



From spectral information to animal colour vision: experiments and concepts  

PubMed Central

Many animals use the spectral distribution of light to guide behaviour, but whether they have colour vision has been debated for over a century. Our strong subjective experience of colour and the fact that human vision is the paradigm for colour science inevitably raises the question of how we compare with other species. This article outlines four grades of ‘colour vision’ that can be related to the behavioural uses of spectral information, and perhaps to the underlying mechanisms. In the first, even without an (image-forming) eye, simple organisms can compare photoreceptor signals to locate a desired light environment. At the next grade, chromatic mechanisms along with spatial vision guide innate preferences for objects such as food or mates; this is sometimes described as wavelength-specific behaviour. Here, we compare the capabilities of di- and trichromatic vision, and ask why some animals have more than three spectral types of receptors. Behaviours guided by innate preferences are then distinguished from a grade that allows learning, in part because the ability to learn an arbitrary colour is evidence for a neural representation of colour. The fourth grade concerns colour appearance rather than colour difference: for instance, the distinction between hue and saturation, and colour categorization. These higher-level phenomena are essential to human colour perception but poorly known in animals, and we suggest how they can be studied. Finally, we observe that awareness of colour and colour qualia cannot be easily tested in animals. PMID:20164101

Kelber, Almut; Osorio, Daniel



Response of Phaseolus vulgaris L. to differing ozone regimes having identical total exposure  

NASA Astrophysics Data System (ADS)

Protocols were designed to test for differences in response of plants to ozone treatments having equal total exposure (concentration × time) but different exposure profiles Kidney beans ( Phaseolus vulgaris L., cv. California Dark Red) were exposed to ozone in controlled fumigation chambers within a greenhouse Four different ozone exposure profiles were used, each having the same total cumulative exposure (SUM00) and the same 7, 12 and 24 h seasonal means. The three exposure profiles which incorporated peak concentrations more severely impacted response parameters compared to a steady-state profile which did not exceed the National Ambient Air Quality Standard. Significant differences were found in percent necrotic leaf area, number of pods and top dry weight between exposure profiles. In additional analyses, the response parameters were regressed against seasonal cumulative ozone concentrations raised to powers of 0.33 and from 0.5 to 4 in steps of 0.5 in order to increase effective weighting of the higher concentrations. Total dry weight and leaf necrosis were best fit with the sum of the squared concentrations ( n = 2) while number of pods was best fit by the summed concentrations to the 3.5 power ( n = 3.5). These analyses suggest the peak ozone concentrations are important in determining plant response.

Musselman, Robert C.; Younglove, Theodore; McCool, Patrick M.


Seasonal Changes in Colour: A Comparison of Structural, Melanin- and Carotenoid-Based Plumage Colours  

PubMed Central

Background Plumage coloration is important for bird communication, most notably in sexual signalling. Colour is often considered a good quality indicator, and the expression of exaggerated colours may depend on individual condition during moult. After moult, plumage coloration has been deemed fixed due to the fact that feathers are dead structures. Still, many plumage colours change after moult, although whether this affects signalling has not been sufficiently assessed. Methodology/Principal Findings We studied changes in coloration after moult in four passerine birds (robin, Erithacus rubecula; blackbird, Turdus merula; blue tit, Cyanistes caeruleus; and great tit, Parus major) displaying various coloration types (melanin-, carotenoid-based and structural). Birds were caught regularly during three years to measure plumage reflectance. We used models of avian colour vision to derive two variables, one describing chromatic and the other achromatic variation over the year that can be compared in magnitude among different colour types. All studied plumage patches but one (yellow breast of the blue tit) showed significant chromatic changes over the year, although these were smaller than for a typical dynamic trait (bill colour). Overall, structural colours showed a reduction in relative reflectance at shorter wavelengths, carotenoid-based colours the opposite pattern, while no general pattern was found for melanin-based colours. Achromatic changes were also common, but there were no consistent patterns of change for the different types of colours. Conclusions/Significance Changes of plumage coloration independent of moult are probably widespread; they should be perceivable by birds and have the potential to affect colour signalling. PMID:20644723

Delhey, Kaspar; Burger, Claudia; Fiedler, Wolfgang; Peters, Anne



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



Accumulation of total mercury and methylmercury in rice plants collected from different mining areas in China.  


A total of 155 rice plants were collected from ten mining areas in three provinces of China (Hunan, Guizhou and Guangdong), where most of mercury (Hg) mining takes place in China. During the harvest season, whole rice plants were sampled and divided into root, stalk & leaf, husk and seed (brown rice), together with soil from root zone. Although the degree of Hg contamination varied significantly among different mining areas, rice seed showed the highest ability for methylmercury (MeHg) accumulation. Both concentrations of total mercury (THg) and MeHg in rice plants were significantly correlated with Hg levels in soil, indicating soil is still an important source for both inorganic mercury (IHg) and MeHg in rice plants. The obvious discrepancy between the distribution patterns of THg and MeHg reflected different pathways of IHg and MeHg accumulation. Water soluble Hg may play more important role in MeHg accumulation in rice plants. PMID:24056187

Meng, Mei; Li, Bing; Shao, Jun-juan; Wang, Thanh; He, Bin; Shi, Jian-bo; Ye, Zhi-hong; Jiang, Gui-bin



Categorical Effects in Children's Colour Search: A Cross-Linguistic Comparison  

ERIC Educational Resources Information Center

In adults, visual search for a colour target is facilitated if the target and distractors fall in different colour categories (e.g. Daoutis, Pilling, & Davies, in press). The present study explored category effects in children's colour search. The relationship between linguistic colour categories and perceptual categories was addressed by…

Daoutis, Christine A.; Franklin, Anna; Riddett, Amy; Clifford, Alexandra; Davies, Ian R. L.



Adaptive colouration in amphibians.  


Amphibians, i.e. salamanders, frogs and caecilians show a wide range of bright colours in combination with contrasting patterns. There is variation among species, populations and also within species and populations. Furthermore, individuals often change colours during developmental stages or in response to environmental factors. This extraordinary variation means that there are excellent opportunities to test hypotheses of the adaptive significance of colours using amphibian species as models. We review the present view of functions of colouration in amphibians with the main focus on relatively unexplored topics. Variation in colouration has been found to play a role in thermoregulation, UV protection, predator avoidance and sexual signalling. However, many proposed cases of adaptive functions of colouration in amphibians remain virtually scientifically unexplored and surprisingly few genes influencing pigmentation or patterning have been detected. We would like to especially encourage more studies that take advantage of recent developments in measurement of visual properties of several possible signalling receivers (e.g. predators, competitors or mates). Future investigations on interactions between behaviour, ecology and vision have the potential to challenge our current view of the adaptive function of colouration in amphibians. PMID:23664831

Rudh, Andreas; Qvarnström, Anna



Quark interactions and colour chemistry  

NASA Astrophysics Data System (ADS)

The interaction between quarks, according to the current theory of quantum chromo-dynamics, is formally rather similar to the electromagnetic interaction between electrons and nucleons, both being governed by locally gauge-invariant field theories. It is tempting therefore to discuss the spectroscopy of hadrons, which are quark composites bound by colour forces, in the same language as the spectroscopy of atoms and molecules which are bound states of electrons and nucleons held together by e.m. forces. Because of the difference in gauge groups, however, the dynamics are very different. Nonetheless, it appears likely that metastable multiquark hadron states can exist which are analogous to atoms and molecules in QED. In these lectures, tentative steps are taken in developing the rudiments of a new ‘colour chemistry’ of these ‘atoms’ and ‘molecules’.

Hong-Mo, Chan


Colour and lighting in hospital design  

NASA Astrophysics Data System (ADS)

Little information or guidance has been available to assist the development of a hospital's visual environment. A report on lighting and colour design schemes, accessible to non professionals with responsibility for refurbishment strategies, was required by NHS Estates. Firstly, 20 hospitals were audited to establish a picture of current practice and to identify key issues where colour design could broadly enhance the environment for patients, staff and visitors. Critical areas were outlined in this report, where colour design can be utilised and applied, for the benefit of all users, from ambience to essential legal requirements such as colour contrast for the visually impaired. Provision of staff relaxation rooms that are different in terms of colour and lux levels from immediate work spaces, or thoughtfully designed areas for patients awaiting intensive treatment, have been shown to have some beneficial effects on a sense of well being. Colour and design have not been established as a definite cure for sickness and ill health, but certainly monotony and poor conditions in premises that have not been refurbished with any care, have had a detrimental affect on recovery rates and staff morale. The realisation that a well balanced and attractive environment is of major importance to patients' health is, in no way new; Florence Nightingale observed that 'a variety of form and brilliance of colour in the objects presented to patients are an actual means of recovery'.

Dalke, Hilary; Little, Jenny; Niemann, Elga; Camgoz, Nilgun; Steadman, Guillaume; Hill, Sarah; Stott, Laura



ColourVis: exploring colour usage in paintings over time  

Microsoft Academic Search

The colour palette of painters over history has been of interest to many, including: art historians, archeologists, and art lovers. Colour usage in art changes from culture to culture and season to season and is often thought of as reflecting or inspiring mood and ambience. We present ColourVis: a visualization that supports exploration of colour usage in digital images. In

Jonathan Haber; Sean Lynch; Sheelagh Carpendale



Quantitative spore colour measurement using colour image analysis  

Microsoft Academic Search

The colour changes that spores exhibit, with increasing depth of burial, are used as a thermal maturity indicator for evaluating hydrocarbon source rocks. Spore colour is determined visually leading to an intrinsic difficulty of unequivocally assessing and recording their colour. Quantitative scales using photometers are available, but are not widely applied. Colour Image Analysis (CIA) is presented here as an

B Yule; S Roberts; J. E. A Marshall; J. A Milton



Bird colour vision: behavioural thresholds reveal receptor noise.  


Birds have impressive physiological adaptations for colour vision, including tetrachromacy and coloured oil droplets, yet it is not clear exactly how well birds can discriminate the reflecting object colours that they encounter in nature. With behavioural experiments, we determined colour discrimination thresholds of chickens in bright and dim light. We performed the experiments with two colour series, orange and green, covering two parts of chicken colour space. These experiments allowed us to compare behavioural results with model expectations and determine how different noise types limit colour discrimination. At intensities ranging from bright light to those corresponding to early dusk (250-10 cd m(-2)), we describe thresholds accurately by assuming a constant signal-to-noise ratio, in agreement with an invariant Weber fraction of Weber's law. Below this intensity, signal-to-noise ratio decreases and Weber's law is violated because photon-shot noise limits colour discrimination. In very dim light (below 0.05cd m(-2) for the orange series or 0.2 cd m(-2) for the green series) colour discrimination is possibly constrained by dark noise, and the lowest intensity at which chickens can discriminate colours is 0.025 and 0.08 cd m(-2) for the orange and green series, respectively. Our results suggest that chickens use spatial pooling of cone outputs to mitigate photon-shot noise. Surprisingly, we found no difference between colour discrimination of chickens and humans tested with the same test in bright light. PMID:25609782

Olsson, Peter; Lind, Olle; Kelber, Almut



Pre-bottling use of dehydrated waste grape skins to improve colour, phenolic and aroma composition of red wines.  


Different dehydrated waste grape skins from the juice industry were added into aged and young red wines as an innovative way of compensating for colour loss before bottling. After addition of grape skins, colour intensity of wines increased a mean 11% and a maximum of 31% with predominance of the red component. Total polyphenols mean increase was 10% with a maximum value of 20%. Analysis of low molecular weight phenolic compounds by HPLC-DAD showed a significant (p<0.05) content increase of the bioactive compounds gallic acid, (+)-catechin, (-)-epicatechin, and (E)-resveratrol. Anthocyanins content also increased at an average of 50mg/l. The volatile profile of wines analysed by SBSE-GC-MS was only moderately influenced by the treatments. Mixtures of dehydrated waste grape skins were useful to improve the colour and polyphenol profile of red wines, considering them a useful tool for correcting colour loss before bottling. PMID:23017417

Pedroza, Miguel Angel; Carmona, Manuel; Alonso, Gonzalo Luis; Salinas, Maria Rosario; Zalacain, Amaya



Three-dimensional plasmonic stereoscopic prints in full colour  

NASA Astrophysics Data System (ADS)

Metal nanostructures can be designed to scatter different colours depending on the polarization of the incident light. Such spectral control is attractive for applications such as high-density optical storage, but challenges remain in creating microprints with a single-layer architecture that simultaneously enables full-spectral and polarization control of the scattered light. Here we demonstrate independently tunable biaxial colour pixels composed of isolated nanoellipses or nanosquare dimers that can exhibit a full range of colours in reflection mode with linear polarization dependence. Effective polarization-sensitive full-colour prints are realized. With this, we encoded two colour images within the same area and further use this to achieve depth perception by realizing three-dimensional stereoscopic colour microprint. Coupled with the low cost and durability of aluminium as the functional material in our pixel design, such polarization-sensitive encoding can realize a wide spectrum of applications in colour displays, data storage and anti-counterfeiting technologies.

Goh, Xiao Ming; Zheng, Yihan; Tan, Shawn J.; Zhang, Lei; Kumar, Karthik; Qiu, Cheng-Wei; Yang, Joel K. W.



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



Signal functions of carotenoid colouration  

E-print Network

The importance of carotenoids for natural colouration, in relation to other classes of pigments and structural colours, has been outlined in Chapter 10. But colour only has significance if it is perceived, identified and interpreted by other organisms (animals). In other words, colour is a means of communication, a signal. Now, in this Chapter, this new direction for carotenoid

Jonathan D. Blount; Kevin J. Mcgraw



Floral colour diversity in plant communities, bee colour space and a null model  

PubMed Central

Evolutionary biologists have long hypothesized that the diversity of flower colours we see is in part a strategy to promote memorization by pollinators, pollinator constancy, and therefore, a directed and efficient pollen transfer between plants. However, this hypothesis has never been tested against a biologically realistic null model, nor were colours assessed in the way pollinators see them. Our intent here is to fill these gaps. Throughout one year, we sampled floral species compositions at five ecologically distinct sites near Berlin, Germany. Bee-subjective colours were quantified for all 168 species. A model of colour vision was used to predict how similar the colours of sympatric and simultaneously blooming flowers were for bees. We then compared flower colour differences in the real habitats with those of random plant communities. We did not find pronounced deviations from chance when we considered common plants. When we examined rare plants, however, we found significant divergence in two of the five plant communities. At one site, similarly coloured species were found to be more frequent than expected, and at the other two locations, flower colours were indistinguishable from a random distribution. These results fit theoretical considerations that rare plants are under stronger selective pressure to secure pollination than common plants. Our study illustrates the power of linking such distinct biological traditions as community ecology and the neuroethology of bee vision.

Gumbert, A.; Kunze, J.; Chittka, L.



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. PMID:20926430

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



Snow effect for total NM intensity and different multiplicities on Mt. Hermon during 1998 - 2014  

NASA Astrophysics Data System (ADS)

All CR stations on mountains and at about sea level at middle and high latitudes in winter periods are covered by snow with the depth (in g/cm2) varied in time. For using these data for space weather forecasting, it is necessary to determine the snow effect for each moment in time and correct observation data not only from barometric and temperature effects (as usual), but also from the snow effect. According to observations on Mt. Hermon, the snow effect in the NM total intensity and different multiplicities is comparable with 11-year variation. The other problem is, that with increasing of snow depth, the sensitivity of the CR detector changed - it moved to higher energies. To determine the snow effect in NM on Mt. Hermon, we made the following investigations step by step: 1) we determined the connection of CR intensity observed on Mt. Hermon during periods without snow with CR intensity on stations which are never covered by snow; 2) by finding the regression coefficients we determine the expected CR variations on Mt. Hermon in winter time on the basis of data of stations which in winter time are not covered by snow; 3) the difference between observed CR intensity and that calculated in point 2 will give the snow effect. This method can be used for any CR station that is covered at some periods by snow. By this method data of CR station can be corrected on snow effect. As an example we determined the snow effect on Mt. Hermon for total neutron intensity and different multiplicities for 1998 - 2014 (the amplitude of this effect in some years reached a big values - more than 40%).

Lev, Dorman; Zukerman, Igor; Pustilnik, Lev; Dai, Uri; Shternlib, Abracham; Shai Applbaum, David; Kazantsev, Vasilii; Kozliner, Lev; Ben Israel, Isaac


Flower colour adaptation in a mimetic orchid  

PubMed Central

Although the tremendous variability in floral colour among angiosperms is often attributed to divergent selection by pollinators, it is usually difficult to preclude the possibility that floral colour shifts were driven by non-pollinator processes. Here, we examine the adaptive significance of flower colour in Disa ferruginea, a non-rewarding orchid that is thought to attract its butterfly pollinator by mimicking the flowers of sympatric nectar-producing species. Disa ferruginea has red flowers in the western part of its range and orange flowers in the eastern part—a colour shift that we hypothesized to be the outcome of selection for resemblance to different local nectar-producing plants. Using reciprocal translocations of red and orange phenotypes as well as arrays of artificial flowers, we found that the butterfly Aeropetes tulbaghia, the only pollinator of the orchid, preferred both the red phenotype and red artificial flowers in the west where its main nectar plant also has red flowers, and both the orange phenotype and orange artificial flowers in the east, where its main nectar plant has orange flowers. This phenotype by environment interaction demonstrates that the flower colour shift in D. ferruginea is adaptive and driven by local colour preference in its pollinator. PMID:22298842

Newman, Ethan; Anderson, Bruce; Johnson, Steven D.



Analysis of differences in bone removal during femoral box osteotomy for primary total knee arthroplasty  

PubMed Central

Purpose this study was conducted to compare the quantity of intercondylar bone removed during femoral box osteotomy for implantation of three contemporary posterior stabilized (PS) total knee arthroplasty designs: Sigma PS (DePuy), Vanguard (Biomet) and Persona (Zimmer). Methods we compared the maximum volumetric bone resection required for the housing of the PS mechanism of these three designs. Bone removal by each PS box cutting jig was three-dimensionally measured. The differences between the three designs were analyzed by the Kruskal-Wallis test. The Mann-Whitney U-test was used for pairwise comparisons. The level of significance was set at p<0.05. Results for small-size implants, the average box osteotomy volume of Persona was significantly smaller than the Vanguard and Sigma PS volumes (p=0.003). The mean difference between Vanguard and Sigma PS (p=0.01) was also significant. For medium size implants, the mean difference between Persona and Sigma PS (p=0.008) and the mean difference between Vanguard and Sigma PS (p=0.01) were statistically significant. For large size implants, the mean difference between Vanguard and Sigma PS (p=0.01) and the mean difference between Sigma PS and Persona (p=0.008) were statistically significant. Conclusions irrespective of implant size, the Persona cutting jig always resected significantly less bone than did Vanguard and Sigma PS. Clinical Relevance although this study does not establish any clinical relevance of removing more or less bone at primary TKA, its results suggest that if a PS design is indicated, it is preferable to select a model which resects less distal femoral bone. PMID:25606547




Bending of light caused by gravitation: the same result via totally different philosophies  

E-print Network

We offer a concise and direct way to derive the bending angle of light (i.e. as generally called, gravitational lensing), while light grazes a star, through the approach suggested earlier by the first author, which is fundamentally based on the energy conservation law and the weak equivalence principle. We come out with the same result as that of the general theory of relativity (GTR), although the philosophies behind are totally different from each other. We emphasize that in our approach, there is no need to draw a distinction between light and ordinary matter, which makes our approach of gravity potentially compatible with quantum mechanics. Furthermore, our equation that furnishes gravitational lensing, also furnishes the result about the precession of the perihelion of a planet. The results obtained are discussed.

Tolga Yarman; Alexander Kholmetskii; Metin Arik



Total mercury in sediments and in Brazilian Ariidae catfish from two estuaries under different anthropogenic influence.  


Santos-São Vicente estuary, located in São Paulo State, Brazil, has a history of contamination by inorganic chemicals such as mercury (Hg). In the 1980s the Cubatão was considered one of the most polluted sites in the world as a consequence of the intense industrial activities located in the city close to the estuary. To provide data and evaluate the local biota, total mercury (THg) contents were determined in sediments and in fish, Cathorops spixii, from different areas of the Santos-São Vicente estuary. For comparison, samples were also collected in a non-polluted system with similar hydrochemistry characteristics, the Cananeia estuary. The water characteristics and THg levels in sediment and fish samples confirmed a high human influence in the Santos-São Vicente estuary. The lowest THg values, observed in Cananeia, were evidence of low anthropogenic influence. High values observed in Santos-São Vicente show the necessity for a monitoring program. PMID:22030105

Azevedo, Juliana S; Braga, Elisabete S; Favaro, Deborah T; Perretti, Adriana R; Rezende, Carlos Eduardo; Souza, Cristina Maria M



Relationship between nine haloacetic acids with total organic halogens in different experimental conditions.  


The effects of pH and bromide ion concentration on the formation of nine haloacetic acids (HAAs) and total organic halogens (TOX) in chlorinated drinking water have been evaluated. In an extensive study, the relationships of nine HAAs with TOX have been investigated. Honesty Significant Differences test (HSD) and ANOVA tests were used for the statistical analyses. The study determined the concentration range of nine HAAs as of a percentage of TOX at varying experimental conditions. Statistical analyses showed that the parameters pH and Br had significant effects on the formation of nine HAAs and TOX. This study also showed that brominated and mixed species of HAAs would be dominant in the presence of high bromide ion concentration which contributes a high percentage of the TOX. The results of this study could be used to set up a maximum contaminant level of TOX as a water quality standard for chlorination by-products. PMID:23551829

Pourmoghadas, Hossein; Kinman, Riley N



Relationship between nine haloacetic acids with total organic halogens in different experimental conditions  

PubMed Central

The effects of pH and bromide ion concentration on the formation of nine haloacetic acids (HAAs) and total organic halogens (TOX) in chlorinated drinking water have been evaluated. In an extensive study, the relationships of nine HAAs with TOX have been investigated. Honesty Significant Differences test (HSD) and ANOVA tests were used for the statistical analyses. The study determined the concentration range of nine HAAs as of a percentage of TOX at varying experimental conditions. Statistical analyses showed that the parameters pH and Br had significant effects on the formation of nine HAAs and TOX. This study also showed that brominated and mixed species of HAAs would be dominant in the presence of high bromide ion concentration which contributes a high percentage of the TOX. The results of this study could be used to set up a maximum contaminant level of TOX as a water quality standard for chlorination by-products. PMID:23551829



A Novel Weighted Total Difference Based Image Reconstruction Algorithm for Few-View Computed Tomography  

PubMed Central

In practical applications of computed tomography (CT) imaging, due to the risk of high radiation dose imposed on the patients, it is desired that high quality CT images can be accurately reconstructed from limited projection data. While with limited projections, the images reconstructed often suffer severe artifacts and the edges of the objects are blurred. In recent years, the compressed sensing based reconstruction algorithm has attracted major attention for CT reconstruction from a limited number of projections. In this paper, to eliminate the streak artifacts and preserve the edge structure information of the object, we present a novel iterative reconstruction algorithm based on weighted total difference (WTD) minimization, and demonstrate the superior performance of this algorithm. The WTD measure enforces both the sparsity and the directional continuity in the gradient domain, while the conventional total difference (TD) measure simply enforces the gradient sparsity horizontally and vertically. To solve our WTD-based few-view CT reconstruction model, we use the soft-threshold filtering approach. Numerical experiments are performed to validate the efficiency and the feasibility of our algorithm. For a typical slice of FORBILD head phantom, using 40 projections in the experiments, our algorithm outperforms the TD-based algorithm with more than 60% gains in terms of the root-mean-square error (RMSE), normalized root mean square distance (NRMSD) and normalized mean absolute distance (NMAD) measures and with more than 10% gains in terms of the peak signal-to-noise ratio (PSNR) measure. While for the experiments of noisy projections, our algorithm outperforms the TD-based algorithm with more than 15% gains in terms of the RMSE, NRMSD and NMAD measures and with more than 4% gains in terms of the PSNR measure. The experimental results indicate that our algorithm achieves better performance in terms of suppressing streak artifacts and preserving the edge structure information of the object. PMID:25275385

Yu, Wei; Zeng, Li



Colour-temperature correspondences: when reactions to thermal stimuli are influenced by colour.  


In our daily lives, information concerning temperature is often provided by means of colour cues, with red typically being associated with warm/hot, and blue with cold. While such correspondences have been known about for many years, they have primarily been studied using subjective report measures. Here we examined this correspondence using two more objective response measures. First, we used the Implicit Association Test (IAT), a test designed to assess the strength of automatic associations between different concepts in a given individual. Second, we used a priming task that involved speeded target discrimination in order to assess whether priming colour or thermal information could invoke the crossmodal association. The results of the IAT confirmed that the association exists at the level of response selection, thus indicating that a participant's responses to colour or thermal stimuli are influenced by the colour-temperature correspondence. The results of the priming experiment revealed that priming a colour affected thermal discrimination reaction times (RTs), but thermal cues did not influence colour discrimination responses. These results may therefore provide important clues as to the level of processing at which such colour-temperature correspondences are represented. PMID:24618675

Ho, Hsin-Ni; Van Doorn, George H; Kawabe, Takahiro; Watanabe, Junji; Spence, Charles



Colour-Temperature Correspondences: When Reactions to Thermal Stimuli Are Influenced by Colour  

PubMed Central

In our daily lives, information concerning temperature is often provided by means of colour cues, with red typically being associated with warm/hot, and blue with cold. While such correspondences have been known about for many years, they have primarily been studied using subjective report measures. Here we examined this correspondence using two more objective response measures. First, we used the Implicit Association Test (IAT), a test designed to assess the strength of automatic associations between different concepts in a given individual. Second, we used a priming task that involved speeded target discrimination in order to assess whether priming colour or thermal information could invoke the crossmodal association. The results of the IAT confirmed that the association exists at the level of response selection, thus indicating that a participant’s responses to colour or thermal stimuli are influenced by the colour-temperature correspondence. The results of the priming experiment revealed that priming a colour affected thermal discrimination reaction times (RTs), but thermal cues did not influence colour discrimination responses. These results may therefore provide important clues as to the level of processing at which such colour-temperature correspondences are represented. PMID:24618675

Ho, Hsin-Ni; Van Doorn, George H.; Kawabe, Takahiro; Watanabe, Junji; Spence, Charles



J.Z.: Ontology-based representation and query colour descriptions from botanical documents  

E-print Network

Abstract. A proper representation of the semantics of colour descriptions is necessary when colour information needs to be processed semantically, such as in the area of information integration. Semantics–based methods can help information from different sources to be integrated more easily and make final results more accurate and understandable among different sources. This paper introduces an ontology–based representation of the semantics of colour descriptions. By using a quantitative colour model and a Description Logic (DL) with datatype support, the semantics of a single colour term can be represented. Multiple such terms are then combined to generate the semantics of a complex colour description, which is interpreted by using morpho–syntactic rules derived from the analysis of colour descriptions in botanical documents. A colour reasoner, interacting with the FaCT-DG DL reasoner, can support colour–related queries and give domain–oriented results. 1

Shenghui Wang; Jeff Z. Pan



Effect of Pretreatment and Drying Method on Colour Degradation Kinetics of Dried Salak Fruit During Storage  

Microsoft Academic Search

Effect of heat treatment on colour stability of dried salak fruit during storage was investigated by using hot air (40–90 °C),\\u000a heat pump (isothermal and intermittent modes, 26–37 °C) and freeze-drying. Influence of pre-treatment on the colour property\\u000a was studied as well by blanching the sample at three levels of temperature (50–70 °C). Total colour change (?E*) was used to assess the colour

Sze Pheng Ong; Chung Lim Law; Ching Lik Hii


Saccades to large coloured targets stepping in open fields.  


Subjects tracked a 2.3 deg target that stepped 5 deg, in a randomly chosen direction, each time it was foveated. Targets were coloured patches that were fairly close to white; in some cases precise matches ensured equiluminosity with the background. Viewing conditions provided good colour rendering and neutral colour adaptation. Pale colours were surprisingly well tracked. Multiple regressions showed that the colour and spatial characteristics of the target are important determinants of a primary saccade's latency. Significant factors included target size, achromatic contrast, tritanopic purity difference, and chromatic saturation. Colour-normal subjects always responded more slowly to yellow or blue targets which a deuteranomalous subject tracked quite well. Severely blurring the target had a consistent minor effect. PMID:7839621

Perron, C; Hallett, P E



A Comparison of the Closed-Face Cassette at Different Orientations While Measuring Total Particles.  


ABSTRACT The current method for sampling aerosols using the 37-mm closed-face cassette (CFC) sampler is based on the orientation of the cassette at ?45° from horizontal. There is some concern as to whether this method is appropriate and may be underestimating exposures. An alternative orientation at ?0° (horizontal) has been discussed. This research compared the CFC's orientation at 45° from horizontal to the proposed orientation at horizontal, 0° in a controlled laboratory setting. The particles used in this study were fused alumina oxide in four sizes, approximately 9.5 ?m, 12.8 ?m, 18 ?m, and 44.3 ?m in aerodynamic diameter. For each test, one aerosol was dispersed in a wind tunnel operating at 0.2 m/s with samplers mounted in the breathing zone of a rotating mannequin. A sampling event consisted of four pairs of samplers, placed side by side (one pair at 45° and another at 0° cassette orientation), and exposed for a period of 45 minutes. A total of twelve sampling events, three sample events per particle size, were conducted with a total of ninety-four samples collected. Mass concentration measurements were compared to assess the relationship between the sampler orientations of the cassettes. In addition, the relationship between the mass collected on the cassette filter and on the interior walls of the cassette was also assessed. The results indicated that there was no significant difference between the measured concentrations based on the orientation of the CFC's. The amount of mass collected on the interior walls of the cassettes were relatively low (<5%) compared to expected (up to 100%) wall losses for both orientations. PMID:25337937

Cook, David M; Sleeth, Darrah K; Thiese, Matthew S; Larson, Rodney R



Colour, vision and ergonomics.  


This paper is based on a research project - Visual Communication and Inclusive Design-Colour, Legibility and Aged Vision, developed at the Faculty of Architecture of Lisbon. The research has the aim of determining specific design principles to be applied to visual communication design (printed) objects, in order to be easily read and perceived by all. This study target group was composed by a selection of socially active individuals, between 55 and 80 years, and we used cultural events posters as objects of study and observation. The main objective is to overlap the study of areas such as colour, vision, older people's colour vision, ergonomics, chromatic contrasts, typography and legibility. In the end we will produce a manual with guidelines and information to apply scientific knowledge into the communication design projectual practice. Within the normal aging process, visual functions gradually decline; the quality of vision worsens, colour vision and contrast sensitivity are also affected. As people's needs change along with age, design should help people and communities, and improve life quality in the present. Applying principles of visually accessible design and ergonomics, the printed design objects, (or interior spaces, urban environments, products, signage and all kinds of visually information) will be effective, easier on everyone's eyes not only for visually impaired people but also for all of us as we age. PMID:22317623

Pinheiro, Cristina; da Silva, Fernando Moreira



Palette-colouring: a belief propagation approach  

NASA Astrophysics Data System (ADS)

We consider a variation of the prototype combinatorial optimization problem known as graph colouring. Our optimization goal is to colour the vertices of a graph with a fixed number of colours, in a way to maximize the number of different colours present in the set of nearest neighbours of each given vertex. This problem, which we pictorially call palette-colouring, has been recently addressed as a basic example of a problem arising in the context of distributed data storage. Even though it has not been proved to be NP-complete, random search algorithms find the problem hard to solve. Heuristics based on a naive belief propagation algorithm are observed to work quite well in certain conditions. In this paper, we build upon the mentioned result, working out the correct belief propagation algorithm, which needs to take into account the many-body nature of the constraints present in this problem. This method improves the naive belief propagation approach at the cost of increased computational effort. We also investigate the emergence of a satisfiable-to-unsatisfiable 'phase transition' as a function of the vertex mean degree, for different ensembles of sparse random graphs in the large size ('thermodynamic') limit.

Pelizzola, Alessandro; Pretti, Marco; van Mourik, Jort



Colour-rendition properties of solid-state lamps  

NASA Astrophysics Data System (ADS)

The applicability of colour-quality metrics to solid-state light sources is validated and the results of the assessment of colour-rendition characteristics of various lamps are presented. The standard colour-rendering index metric or a refined colour-quality scale metric fails to distinguish between two principle colour-rendition properties of illumination: the ability to render object colours with high fidelity and the ability to increase chromatic contrast, especially when the spectra of light sources contain a few narrow-band electroluminescence components. Supplementing these metrics by the known figures of merit that measure the gamut area of a small number of test colour samples does not completely resolve this issue. In contrast, the statistical approach, which is based on sorting a very large number of test colour samples in respect of just-perceivable colour distortions of several kinds, offers a comprehensive assessment of colour-rendition properties of solid-state light sources. In particular, two statistical indices, colour-fidelity index (CFI) and colour-saturation index (CSI), which are the relative numbers of object colours rendered with high fidelity and increased saturation, respectively, are sufficient to reveal and assess three distinct types of solid-state light sources. These are (i) high-fidelity lamps, which cover the entire spectrum with the spectral components present in the wavelength ranges of both 530-610 nm and beyond 610 nm (e.g. trichromatic warm white phosphor-converted (pc) light-emitting diodes (LEDs), red-amber-green-blue LED clusters, complementary clusters of white and coloured LEDs); (ii) colour-saturating lamps, which lack power in the 530-610 nm wavelength range (e.g. red-green-blue or red-cyan-blue LED clusters) and (iii) colour-dulling lamps, which lack power for wavelengths longer than 610 nm (dichromatic daylight pc LEDs and amber-green-blue LED clusters). Owing to a single statistical format, CSI and CFI can be used for design and optimization of multiwavelength LED clusters providing 'smart' illumination with a trade-off between different colour-rendition characteristics.

Žukauskas, A.; Vaicekauskas, R.; Shur, M. S.



No role for colour in symmetry perception  

Microsoft Academic Search

Bilateral colour symmetry, such as that evident in a Siberian tiger's face (Fig. 1a), is relevant to many animals,, including humans,. We examined the role of colour in symmetry perception by asking observers to detect colour symmetry in regular grids of coloured squares (a colour-symmetrical image has regions of the same colour located equidistantly from a vertical axis). Our results

Dawn Morales; Harold Pashler



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. PMID:22937744



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. PMID:24893601



Monitoring coral bleaching using a colour reference card  

Microsoft Academic Search

Assessment of the extent of coral bleaching has become an important part of studies that aim to understand the condition of coral reefs. In this study a reference card that uses differences in coral colour was developed as an inexpensive, rapid and non-invasive method for the assessment of bleaching. The card uses a 6 point brightness\\/saturation scale within four colour

U. E. Siebeck; N. J. Marshall; A. Klüter; Ove Hoegh-Guldberg



Development of a forensic skin colour predictive test.  


There is growing interest in skin colour prediction in the forensic field. However, a lack of consensus approaches for recording skin colour phenotype plus the complicating factors of epistatic effects, environmental influences such as exposure to the sun and unidentified genetic variants, present difficulties for the development of a forensic skin colour predictive test centred on the most strongly associated SNPs. Previous studies have analysed skin colour variation in single unadmixed population groups, including South Asians (Stokowski et al., 2007, Am. J. Hum. Genet, 81: 1119-32) and Europeans (Jacobs et al., 2013, Hum Genet. 132: 147-58). Nevertheless, a major challenge lies in the analysis of skin colour in admixed individuals, where co-ancestry proportions do not necessarily dictate any one person's skin colour. Our study sought to analyse genetic differences between African, European and admixed African-European subjects where direct spectrometric measurements and photographs of skin colour were made in parallel. We identified strong associations to skin colour variation in the subjects studied from a pigmentation SNP discovery panel of 59 markers and developed a forensic online classifier based on naïve Bayes analysis of the SNP profiles made. A skin colour predictive test is described using the ten most strongly associated SNPs in 8 genes linked to skin pigmentation variation. PMID:25082135

Maroñas, Olalla; Phillips, Chris; Söchtig, Jens; Gomez-Tato, Antonio; Cruz, Raquel; Alvarez-Dios, José; de Cal, María Casares; Ruiz, Yarimar; Fondevila, Manuel; Carracedo, Ángel; Lareu, María V



Measuring the colour of rendering mortars  

NASA Astrophysics Data System (ADS)

When restoring decorative mortar layers on historic façades, professionals need to determine the colour of these finishes in order to select an appropriate repair mortar. Currently, the appearance of these renders is only assessed from a subjective point of view. To match with the aesthetic aspects of the façade, contractors must constantly adjust their repair mortar composition to avoid a patchwork of different colours, which is detrimental for heritage. This time-consuming (trial-and-error) methodology can be excluded by evaluating `colour' with an objective numerical approach. The challenge of the research was to define and evaluate optimal material dependent boundary conditions for measuring the colour of nonhomogeneous mortars. Four samples with different scale of heterogeneity were measured by two spectrocolorimeters, both with a diffuse illumination geometry. The results were plotted in CIE-L*a*b* colour space. By calculating the colour difference (?E*), the influence of measuring with or without specular component was evaluated. We discovered the minimal number of measuring points depends on the scale of heterogeneity and the aperture area. The less homogeneous the mortar sample is and the smaller the aperture area, the more unique measuring points are required. Therefore, it is recommended to choose an aperture head of 25 mm or more to reduce the number of measurements, making your work time-efficient. However, in order to obtain accurate measurements on site, a portable optical spectrum analyser can be used with a 6 mm-diameter aperture, a viewing angle of 10°, SCI mode, illumination source D65, considering a minimum of 15 unique measuring points.

Govaerts, Yves; Meulebroeck, Wendy; Verdonck, Ann; de Bouw, Michael



Variation in Differential and Total Cross Sections Due to Different Radial Wave Functions  

ERIC Educational Resources Information Center

Three sets of analytical wave functions are used to calculate the Na (3s---3p) transition differential and total electron excitation cross sections by Born approximations. Results show expected large variations in values. (Author/CP)

Williamson, W., Jr.; Greene, T.



On the colour-colour properties of the Extremely Red Objects  

NASA Astrophysics Data System (ADS)

The colours of the galaxy class known as Extremely Red Objects (EROs; R-K>5) are considered to be consistent with two distinct galaxy populations at high redshift: evolved ellipticals or young dusty starbursts. In this paper the properties of EROs, spanned by the five photometric bands RIJHK, are investigated as to the possibility to distinguish between these two galaxy populations using only broad band photometry. The broad band colours of elliptical and starburst galaxies at redshifts up to 5 are computed from synthetic spectra obtained using the spectral evolution synthesis programme PÉGASE.2. Two initial mass functions and a range of metallicities and extinctions are used. In order to be extremely red in the redshift range considered, the evolution of the R-K colour sets the requirement that ellipticals have to be less than 7-8 Gyr old, and that the starbursts must have colour excesses of E(B-V)>1, as derived from the nebular emission lines. In investigating the overlap in the different colour-colour planes as a function of redshift, it is found that the planes formed from permutations of the same three filters exhibit very similar overlap characteristics. In colour-colour planes formed within such triplets one of the filters will serve as a ``pivot'' band against which the two other bands are compared. The configuration where this pivot band lies between the other two bands has the best performance as a discriminator among the three possible configurations. A consistent behaviour cannot be found among the configurations formed by permuting four filters. The minimal filter configuration R-H vs. H-K is found to be the very best discriminator, working as such up to redshift 2.9.

Bergström, S.; Wiklind, T.



Dichromats Detect Colour-Camouflaged Objects that are not Detected by Trichromats  

Microsoft Academic Search

To explain the surprisingly high frequency of congenital red--green colour blindness, the suggestion has been made that dichromats might be at an advantage in breaking certain kinds of colour camouflage. We have compared the performance of dichromats and normal observers in a task in which texture is camouflaged by colour. The texture elements in a target area differed in either

M. J. Morgan; A. Adam; J. D. Mollon



REVIEW PAPER Visual ecology of aphids--a critical review on the role of colours  

E-print Network

REVIEW PAPER Visual ecology of aphids--a critical review on the role of colours in host finding of aphids (Hemiptera: Aphididae) to stimuli of different colours. Only in one species there are adequate of the great interest in aphid responses to coloured targets from an evolutionary, ecological and applied

Chittka, Lars


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



Coloured marking inside glass by laser radiation  

NASA Astrophysics Data System (ADS)

Laser labelling inside glass induces micro-cracks by high energy densities in the focus. The micro-cracks reduce the mechanical stability of glass. Light scattering allows the observer to perceive the cracks as white pixels. Coloured marking of glass in this manner is not possible. Coloured marking inside glass by changing the oxidation state of the metal ions locally in the focus does not weaken the mechanical properties of the glass. Two kind of glass systems, lime-natron-silicate and borosilicate with 0.5 % mass-content of doping are investigated. The simultaneous presence of donators and acceptors allows a transition of electrons between polyvalent ions, and can lead to permanent colour-centres inside the glass, due to the fact that the absorption of the polyvalent ions is changed by the laser-induced conversion process. For this purpose a 3 ? Nd:YAG (wavelength ?L = 355 nm, pulse duration t = 10 to 80 ns) and a Ti:Sapphire solid-state laser (wavelength ?L = 810 nm, pulse duration t = 200 fs) are used. The radiation parameters and the chemical composition of the glass (mainly doping) are the dominant factors to generate coloured marking. The transmittance as a function of the fluence and the change of the absorption coefficient is measured and gives a statement of the colourshade. Further the difference between lime-natron-silicate and borosilicate glass (same doping variety) is examined. Actually mauve, yellow, red-brown an grey colouring can be produced. Cracks in the microstructure of glass can also be the cause for brown colour-centres generating.

Ligbado, Grace; Horn, Alexander; Kreutz, Ernst W.; Krauss, Manfred M.; Siedow, Norbert; Hensel, Hartmut



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



Targeting for energy efficiency and improved energy collaboration between different companies using total site analysis (TSA)  

Microsoft Academic Search

Rising fuel prices, increasing costs associated with emissions of green house gases and the threat of global warming make efficient use of energy more and more important. Industrial clusters have the potential to significantly increase energy efficiency by energy collaboration. In this paper Sweden’s largest chemical cluster is analysed using the total site analysis (TSA) method. TSA delivers targets for

Roman Hackl; Eva Andersson; Simon Harvey



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



Modulation of total ceramide and constituent ceramide species in the acutely and chronically hypoxic mouse heart at different ages  

Microsoft Academic Search

Ceramide has been implicated in regulatory processes vital for cell survival under different stressors, most notably hypoxia. Little has been done to investigate the contributions of the different ceramide species to the regulation of cell survival. This study aims to highlight the patterns of variation in total ceramide and its species in the growing and hypoxic mouse heart. Mus musculus

Lama Noureddine; Raed Azzam; Georges Nemer; Jacek Bielawski; Michel Nasser; Fadi Bitar; Ghassan S. Dbaibo



Influence of the apparent molecular size of aquatic humic substances on colour removal by coagulation and filtration.  


This study aims to verify the influence of the apparent molecular size of aquatic humic substances (AHSs) on the effectiveness of coagulation with aluminium sulphate and ferric chloride. Coagulation-filtration tests using the jar test and bench-scale sand filters were carried out with water samples having a true colour of approximately 100 Hazen units and prepared with AHSs of different molecular sizes. Stability diagrams are presented showing regions of > or = 90% and > or = 95% apparent colour removal delineated for each water sample using plots of total metal ion concentration (Al3+ and Fe3+) versus coagulation pH. To achieve the same degree of colour removal, the water samples with smaller apparent molecular sizes and a higher percentage of fulvic acids required higher dosages of both aluminium sulphate and ferric chloride. PMID:22439564

Rigobello, Eliane Sloboda; Dantas, Angela Di Bernardo; Di Bernardo, Luiz; Vieira, Eny Maria



Implementation and characterization of a fibre-optic colour sensor  

NASA Astrophysics Data System (ADS)

In this paper the implementation of a fibre-optic sensor for colour detection based on reflective colour sensing is proposed. The sensor consists of three plastic optical fibres emitting red, green and blue components and one optical fibre collecting light reflected from the object. Red, green and blue LEDs are excited at different frequencies. In this way detection of the reflected signal is achieved with only one photodetector and three bandpass filters. Bandpass filters are implemented as digital IIR (infinite impulse response) filters on the microcontroller. Results obtained from the proposed sensor are compared with commercial available colour sensors and the results are satisfactory. Analyses of the sensor performance both in RGB and HSV colour space are done. The proposed solution shows that in specific applications by using the HSV model the sensor can be used both as a colour and distance sensor.

Baji?, Jovan S.; Stupar, Dragan Z.; Daki?, Bojan M.; Manojlovi?, Lazo M.; Slankamenac, Miloš P.; Živanov, Miloš B.



Why do seals have cones? Behavioural evidence for colour-blindness in harbour seals.  


All seals and cetaceans have lost at least one of two ancestral cone classes and should therefore be colour-blind. Nevertheless, earlier studies showed that these marine mammals can discriminate colours and a colour vision mechanism has been proposed which contrasts signals from cones and rods. However, these earlier studies underestimated the brightness discrimination abilities of these animals, so that they could have discriminated colours using brightness only. Using a psychophysical discrimination experiment, we showed that a harbour seal can solve a colour discrimination task by means of brightness discrimination alone. Performing a series of experiments in which two harbour seals had to discriminate the brightness of colours, we also found strong evidence for purely scotopic (rod-based) vision at light levels that lead to mesopic (rod-cone-based) vision in other mammals. This finding speaks against rod-cone-based colour vision in harbour seals. To test for colour-blindness, we used a cognitive approach involving a harbour seal trained to use a concept of same and different. We tested this seal with pairs of isoluminant stimuli that were either same or different in colour. If the seal had perceived colour, it would have responded to colour differences between stimuli. However, the seal responded with "same", providing strong evidence for colour-blindness. PMID:25452008

Scholtyssek, Christine; Kelber, Almut; Dehnhardt, Guido



Assessment of Antioxidant Potential, Total Phenolics and Flavonoids of Different Solvent Fractions of Monotheca Buxifolia Fruit  

PubMed Central

Objectives This study was conducted to investigate the antioxidant potential of methanol extract and its derived fractions (hexane, ethyl acetate, butanol, and aqueous) of fruits of Monotheca buxifolia (Falc.) Dc., a locally used fruit in Pakistan. Methods Dried powder of the fruit of M. buxifolia was extracted with methanol and the resultant was fractionated with solvents having escalating polarity; n-hexane, chloroform, ethyl acetate, n-butanol and the residual soluble aqueous fraction. Total phenolic and total flavonoid contents were estimated for the methanol and various fractions. These fractions were also subjected to various in vitro assays to estimate the scavenging activity for 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), superoxide, hydroxyl, hydrogen peroxide and reductive ability for ferric ions and phosphomolybdate assay. Results The n-butanol, aqueous and methanol fractions possessed high amount of phenolics and flavonoids compared with other fractions, and subsequently showed a pronounced scavenging activity on DPPH, ABTS, superoxide, hydroxyl and hydrogen peroxide radicals and had a potent reductive ability on ferric ion and phosphomolybdate assay. There was a found significant correlation between total phenolic and flavonoid contents and EC50 of DPPH, superoxide, hydrogen peroxide radical and phosphomolybdate assays, whereas a nonsignificant correlation was found with the hydroxyl radical and ABTS radical assay. Conclusion M. buxifolia fruit can be used as natural antioxidant source to prevent damage associated with free radicals. PMID:24298440

Jan, Shumaila; Khan, Muhammad Rashid; Rashid, Umbreen; Bokhari, Jasia



Quantitative Luminance And Colour Representation With CRT Displays  

NASA Astrophysics Data System (ADS)

Colour displays in image processing admit grey scales as well as colour scales for the visual representation of image information. Pseudocolours can be used to enhance the discriminability of different parts of the image. Luminance scales, on the other hand, are preferred for representing fine detail as human colour vision is limited to relatively low spatial frequencies. In the present paper, the generation of quantitative luminance and colour scales with CRT displays is discussed. This includes the colour characteristics of CRTs as well as a recapitulation of the CIE 1931 (X, Y, Z) tristimulus colorimetry system. The CIE 1976 UCS diagram (u', v') is used as an approximation to a perceptually uniform representation of chromaticity. On this basis, it is shown how, for each pixel, luminance and colour (hue) can be chosen independently. In order to add colour as a further visual dimension to greyscale images, a set of equiluminant hues is proposed for each luminance level. The hues are chosen from equidistant steps around a circle in the (u', v') chromaticity diagram. This choice of colours is particularly suitable for the visual representation of a cyclic quantity like phase angle.

Brettel, Hans



Colour mimicry and sexual deception by Tongue orchids (Cryptostylis).  


Typically, floral colour attracts pollinators by advertising rewards such as nectar, but how does colour function when pollinators are deceived, unrewarded, and may even suffer fitness costs? Sexually deceptive orchids are pollinated only by male insects fooled into mating with orchid flowers and inadvertently transferring orchid pollinia. Over long distances, sexually deceptive orchids lure pollinators with counterfeit insect sex pheromones, but close-range deception with colour mimicry is a tantalising possibility. Here, for the first time, we analyse the colours of four sexually deceptive Cryptostylis orchid species and the female wasp they mimic (Lissopimpla excelsa, Ichneumonidae), from the perspective of the orchids' single, shared pollinator, male Lissopimpla excelsa. Despite appearing different to humans, the colours of the orchids and female wasps were effectively identical when mapped into a hymenopteran hexagonal colour space. The orchids and wasps reflected predominantly red-orange wavelengths, but UV was also reflected by raised bumps on two orchid species and by female wasp wings. The orchids' bright yellow pollinia contrasted significantly with their overall red colour. Orchid deception may therefore involve accurate and species-specific mimicry of wavelengths reflected by female wasps, and potentially, exploitation of insects' innate attraction to UV and yellow wavelengths. In general, mimicry may be facilitated by exploiting visual vulnerabilities and evolve more readily at the peripheries of sensory perception. Many sexually deceptive orchids are predominantly red, green or white: colours that are all potentially difficult for hymenoptera to detect or distinguish from the background. PMID:19798479

Gaskett, A C; Herberstein, M E



Colour mimicry and sexual deception by Tongue orchids ( Cryptostylis)  

NASA Astrophysics Data System (ADS)

Typically, floral colour attracts pollinators by advertising rewards such as nectar, but how does colour function when pollinators are deceived, unrewarded, and may even suffer fitness costs? Sexually deceptive orchids are pollinated only by male insects fooled into mating with orchid flowers and inadvertently transferring orchid pollinia. Over long distances, sexually deceptive orchids lure pollinators with counterfeit insect sex pheromones, but close-range deception with colour mimicry is a tantalising possibility. Here, for the first time, we analyse the colours of four sexually deceptive Cryptostylis orchid species and the female wasp they mimic ( Lissopimpla excelsa, Ichneumonidae), from the perspective of the orchids’ single, shared pollinator, male Lissopimpla excelsa. Despite appearing different to humans, the colours of the orchids and female wasps were effectively identical when mapped into a hymenopteran hexagonal colour space. The orchids and wasps reflected predominantly red-orange wavelengths, but UV was also reflected by raised bumps on two orchid species and by female wasp wings. The orchids’ bright yellow pollinia contrasted significantly with their overall red colour. Orchid deception may therefore involve accurate and species-specific mimicry of wavelengths reflected by female wasps, and potentially, exploitation of insects’ innate attraction to UV and yellow wavelengths. In general, mimicry may be facilitated by exploiting visual vulnerabilities and evolve more readily at the peripheries of sensory perception. Many sexually deceptive orchids are predominantly red, green or white: colours that are all potentially difficult for hymenoptera to detect or distinguish from the background.

Gaskett, A. C.; Herberstein, M. E.



Colouring Non-sparse Random Intersection Graphs  

NASA Astrophysics Data System (ADS)

An intersection graph of n vertices assumes that each vertex is equipped with a subset of a global label set. Two vertices share an edge when their label sets intersect. Random Intersection Graphs (RIGs) (as defined in [18,32]) consider label sets formed by the following experiment: each vertex, independently and uniformly, examines all the labels (m in total) one by one. Each examination is independent and the vertex succeeds to put the label in her set with probability p. Such graphs nicely capture interactions in networks due to sharing of resources among nodes. We study here the problem of efficiently coloring (and of finding upper bounds to the chromatic number) of RIGs. We concentrate in a range of parameters not examined in the literature, namely: (a) m = n ? for ? less than 1 (in this range, RIGs differ substantially from the Erdös-Renyi random graphs) and (b) the selection probability p is quite high (e.g. at least ln^2{n}/m in our algorithm) and disallows direct greedy colouring methods.

Nikoletseas, Sotiris; Raptopoulos, Christoforos; Spirakis, Paul G.


Lighting environment predicts the relative abundance of male colour morphs in bluefin killifish (Lucania goodei) populations.  

PubMed Central

Animal communication occurs when an animal emits a signal, the signal is transmitted through the environment, and then detected by the receiver. The environment in which signalling occurs should govern the efficacy of this process. In this study, I examine the relationship of lighting environment (light transmission and tree cover), location and the relative abundances of male colour morphs across seven drainages and 30 populations in the bluefin killifish, Lucania goodei. I found that males with blue anal fins were more common in populations with low transmission of ultraviolet (UV) and blue wavelengths. By contrast, males with red anal fins (and to a lesser extent, males with yellow anal fins) were more common in populations with high transmission of UV and blue wavelengths. High UV-blue light transmission should create a blue visual background and may make blue males less conspicuous and red males more conspicuous to conspecifics. Colour contrast with the visual background may be more important than total brightness of the colour pattern. These results indicate that natural selection for effective intraspecific communication drives the relative abundance of male colour morphs in different lighting habitats. PMID:12137575

Fuller, Rebecca C



SingleColour and SingleFlavour Colour Superconductivity  

E-print Network

Chromodynamics (QCD) predicts that at high density, such as that found within the core of a compact star, cold interactions, as is required when modelling compact stars, the situation changes. These e#ects introduce colour a study of single­flavour and other spin­1 colour supercon­ ducting condensates in a survey of generic

Low, Robert


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



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



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



Thermographic method for evaluation of thermal influence of exterior surface colour of buildings  

NASA Astrophysics Data System (ADS)

Architecture colour is an important part in urban designing. It directly affects the expressing and the thermal effect of exterior surface of buildings. It has proved that four factors affect the sign visibility, graphics, colour, lighting condition and age of the observers, and colour is the main aspect. The best method is to prevent the exterior space heating up in the first place, by reflecting heat away room the exterior surface.The colour of paint to coat building's exterior wall can have a huge impact on energy efficiency. While the suitable colour is essential to increasing the energy efficiency of paint colour during the warm summer months, those products also help paint colour efficiency and reduce heat loss from buildings during winter months making the interior more comfortable all year long. The article is based on analyzing the importance of architecture color design and existing urban colour design. The effect of external surface colour on the thermal behaviour of a building has been studied experimentally by Infrared Thermographic method in University of Science and technology Beijing insummer.The experimental results showed that different colour has quietly different thermal effect on the exterior surface of buildings. The thermal effect of carmine and fawn has nearly the same values. The main factor which is color express, give some suggest ting about urban color design. The investigation reveals that the use of suitable surface colour can dramatically reduce maximum the temperatures of the exterior wall. Keywords: architectural colour, thermal, thermographic

Wu, Yanpeng; Li, Deying; Jin, Rendong; Liu, Li; Bai, Jiabin; Feng, Jianming



Individual differences in physiologic measures are stable across repeated exposures to total sleep deprivation  

PubMed Central

Abstract Some individuals show severe cognitive impairment when sleep deprived, whereas others are able to maintain a high level of performance. Such differences are stable and trait?like, but it is not clear whether these findings generalize to physiologic responses to sleep loss. Here, we analyzed individual differences in behavioral and physiologic measures in healthy ethnic?Chinese male volunteers (n = 12; aged 22–30 years) who were kept awake for at least 26 h in a controlled laboratory environment on two separate occasions. Every 2 h, sustained attention performance was assessed using a 10?min psychomotor vigilance task (PVT), and sleepiness was estimated objectively by determining percentage eyelid closure over the pupil over time (PERCLOS) and blink rate. Between?subject differences in heart rate and its variability, and electroencephalogram (EEG) spectral power were also analyzed during each PVT. To assess stability of individual differences, intraclass correlation coefficients (ICC) were determined using variance components analysis. Consistent with previous work, individual differences in PVT performance were reproducible across study visits, as were baseline sleep measures prior to sleep deprivation. In addition, stable individual differences were observed during sleep deprivation for PERCLOS, blink rate, heart rate and its variability, and EEG spectral power in the alpha frequency band, even after adjusting for baseline differences in these measures (range, ICC = 0.67–0.91). These findings establish that changes in ocular, ECG, and EEG signals are highly reproducible across a night of sleep deprivation, hence raising the possibility that, similar to behavioral measures, physiologic responses to sleep loss are trait?like. PMID:25263200

Chua, Eric Chern?Pin; Yeo, Sing?Chen; Lee, Ivan Tian?Guang; Tan, Luuan?Chin; Lau, Pauline; Tan, Sara S.; Ho Mien, Ivan; Gooley, Joshua J.



Determination of total flavonoids content in fresh Ginkgo biloba leaf with different colors using near infrared spectroscopy  

NASA Astrophysics Data System (ADS)

Total flavonoids content is often considered an important quality index of Ginkgo biloba leaf. The feasibility of using near infrared (NIR) spectra at the wavelength range of 10,000-4000 cm-1 for rapid and nondestructive determination of total flavonoids content in G. biloba leaf was investigated. 120 fresh G. biloba leaves in different colors (green, green-yellowish and yellow) were used to spectra acquisition and total flavonoids determination. Partial least squares (PLS), interval partial least squares (iPLS) and synergy interval partial least squares (SiPLS) were used to develop calibration models for total flavonoids content in two colors leaves (green-yellowish and yellow) and three colors leaves (green, green-yellowish and yellow), respectively. The level of total flavonoids content for green, green-yellowish and yellow leaves was in an increasing order. Two characteristic wavelength regions (5840-6090 cm-1 and 6620-6880 cm-1), which corresponded to the absorptions of two aromatic rings in basic flavonoid structure, were selected by SiPLS. The optimal SiPLS model for total flavonoids content in the two colors leaves (r2 = 0.82, RMSEP = 2.62 mg g-1) had better performance than PLS and iPLS models. It could be concluded that NIR spectroscopy has significant potential in the nondestructive determination of total flavonoids content in fresh G. biloba leaf.

Shi, Ji-yong; Zou, Xiao-bo; Zhao, Jie-wen; Mel, Holmes; Wang, Kai-liang; Wang, Xue; Chen, Hong


Antioxidant activity and total phenols in different extracts of four Staphylea L. Species.  


Staphylea L. is a deciduous ornamental shrub that possesses significant cytotoxic and antibacterial activity, although the chemical composition of its extracts and the identity of the structures responsible for these biological activities are not yet known. In this study we have determined the total phenolic content in chloroform and ethyl acetate extracts of four Staphylea species: Staphylea colchica Stev., S. elegans Zab., S. holocarpa Hemsl. and S. pinnata L.. The antioxidant potential (DPPH radical and peroxynitrite scavenging activity) of these extracts was also determined and a correlation between the phenolic content and antioxidant activities of the ethyl acetate extracts has been found. Ethyl acetate extracts were more active and one of them, obtained from S. colchica Stev., possessed the highest activity. PMID:17693956

Lacikova, Lubica; Muselik, Jan; Masterova, Irena; Grancai, Daniel



Ozone total column and surface comparisons during differing meteorological conditions at Edgewood, MD during summer 2011  

NASA Astrophysics Data System (ADS)

Chemical and meteorological measurements were taken during 01 July - 31 July, 2011 in the Mid-Atlantic region as a part of the first year of NASA's DISCOVER-AQ (Deriving Information on Surface Conditions from COlumn and VERtically Resolved Observations Relevant to Air Quality) campaign. The main objective of the project is to relate total column amounts to surface amounts of constituents related to air quality for the improvement of satellite interpretation and diagnosis of surface pollution. The Nittany Atmospheric Trailer and Integrated Validation Experiment (NATIVE) trailer was deployed to Aberdeen Proving Ground in Edgewood, MD during the campaign to provide in-situ, ground-based air quality measurements. NATIVE surface data, as well as coincident free-flying and tethered balloon ozone profiles are compared with observations from a NASA P3B aircraft performing profile spirals directly over the Edgewood site. Phenomena such as bay breeze circulations and their effect on surface and column pollution amounts are also investigated.

Stauffer, R. M.; Martins, D. K.; Halliday, H. S.; Thompson, A. M.; Weinheimer, A. J.; Knapp, D. J.; Montzka, D.; Clark, R. D.




Microsoft Academic Search

The colour terms of Irish have been discussed by a number of scholars, usually with an emphasis on Old Irish or in comparison with other Celtic languages. Lazar-Meyn (1991) has in addition interviewed speakers of the modern Celtic languages in order to study their use of colour terms, although she correctly notes that this area of the lexicon has come

Diarmuid Ó Sé


Total number of planetary nebulae in different galaxies and the PN distance scale.  

NASA Astrophysics Data System (ADS)

RESUMEN A partir de una muestra de quince galaxias se encuentra que la tasa de natalidad de nebulosas planetarias por unidad de luminosidad, , disminuye al aumentar la luminosidad y al aumentar (B - V)0. Se discuten posibles explicaciones para estos resultados. Se estima el valor de para la Galaxia y a partir de el se encuentra que el numero total de nebulosas planetarias en nuestra galaxia con R < 0.64 pc- es de 7200 j 1800. El valor galactico de implica que la mayorfa de las estrellas de masa intermedia pasa por la etapa de nebulosa planetaria. El valor galactico de , la tasa de mortalidad estelar por unidad de luminosidad y la tasa de natalidad de enanas blancas favorecen escalas de distancias largas para nebulosas planetarias, como la de Cudworth (1974) y la de Mallik y Peimbert (1988). ABSTRACT From a sample of fifteen galaxies it is found that the birth rate of PN per unit luminosity, , decreases with increasing luminosity and with increasing (B - V)0 possible reasons for these relationships are discussed. The value for the Galaxy is estimated and, from it, a total number of PN of 7200 # 1800 wid R < 0.64 pc is obtained. The galactic value implies that most of the intermediate mass stars go through the PN stage. The galactic value, the stellar death rate per unit luminosity and the white dwarf birth rate are in favor of long distance scales to PN like those of Cudworth (1974) and Mallik and (1988). Key wonis: NEBULAE.PLANETARY - STARS-EVOLUTION - STARS-SThLIAR STA. S

Peimbert, M.



Relative changes in tocopherols, isoflavones, total phenolic content, and antioxidative activity in soybean seeds at different reproductive stages.  


Immature seeds of soybean are becoming increasingly popular as a snack/vegetable to harness the health benefits of soybean. They are shelled from the immature pods picked from the mother plant at different reproductive stages. Information concerning changes in antioxidant constituents and antioxidant capacity during reproductive phases of soybean seeds is scarce. The aim of the present study was to determine whether immature seeds picked at different reproductive stages differ in tocopherol, isoflavone, total phenolic contents, free radical scavenging activity, and total antioxidative capacity. Seeds shelled from the soybean pods picked at three reproductive stages (R5, R6, and R7) as well as at full maturity were subjected to high-performance liquid chromatography analyses for tocopherol and isoflavone contents. Significantly higher values (P<0.05) were observed for tocopherols and isoflavones in immature seeds picked at late reproductive stages. At the first reproductive stage, that is, R5 stage, delta-tocopherol was the predominant form of tocopherol, whereas in subsequent reproductive stages as well as at complete maturity stage, the gamma-isomer contributed maximum proportion to the total tocopherol content. Genistein was, in general, the major form of isoflavone at all reproductive stages. Reduction in free radical scavenging activity, total antioxidant capacity, and total phenolic content in late-picked seeds concomitant with increased concentration of tocopherol and isoflavone isomers was observed. The results show that bioactive constituents other than isoflavones and tocopherols may decline with the advancement of maturity. PMID:19256542

Kumar, Vineet; Rani, Anita; Dixit, Amit Kumar; Bhatnagar, Deepak; Chauhan, G S



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. PMID:24039297

Baldwin, Carole C



Colouring mechanism of dyed KDP crystal by quantum chemistry  

Microsoft Academic Search

Dye adsorption mechanism, in particular, colouring mechanism of KDP (KH2PO4) crystal was investigated by quantum chemistry in this study. Phenomena, such as different preferentially coloured faces of KDP when co-crystallised with different dyes, are explained by the minimum and maximum values of electrostatic potential (ESP). Furthermore, it is found that the ESP distribution of a dye molecule may not necessarily

Yusuke Asakuma; Motosuke Nishimura; Qin Li; H. Ming Ang; Moses Tade; Kouji Maeda; Keisuke Fukui



Differences in Total Medical Costs Across the SSRIs for the Treatment of Depression and Anxiety  

Microsoft Academic Search

There is growing evidence that adherence to the recommended duration of antidepressant therapy results in reduced medical costs compared with non- adherence, and that the likelihood of adhering to therapy is not equivalent across the selective sero- tonin reuptake inhibitors (SSRIs). As such, the pur- pose of this study was to assess differences in 6-month medical costs between paroxetine con-

David V. Sheehan; Michael T. Eaddy; Manan B. Shah; Robert P. Mauch



Microbiology and Immunology Requirements 2012-13 Course requirements (Total of 8 different courses, not including Research)  

E-print Network

Microbiology and Immunology Requirements 2012-13 Course requirements (Total of 8 different courses, not including Research) Aut: BIOS 200 The Nucleus (8 units) MI 250* Frontiers in Microbiology & Immunology (1 The Responsible Conduct of Research (1 unit) Spr: MI 204 Innate Immunology (3 units) MI 215 Principles

Sonnenburg, Justin L.


Microbiology and Immunology Requirements 2014-15 Course requirements (Total of 8 different courses, not including Graduate Research)  

E-print Network

Microbiology and Immunology Requirements 2014-15 Course requirements (Total of 8 different courses Foundations in Experimental Biology 6 units MI 250* Frontiers in Microbiology & Immunology 1 unit MI 399 The Responsible Conduct of Research 1 unit Spring MI 204 Innate Immunology 3 units MI 215 Principles of Biological

Sonnenburg, Justin L.


Microbiology and Immunology Requirements 2013-14 Course requirements (Total of 8 different courses, not including Graduate Research)  

E-print Network

Microbiology and Immunology Requirements 2013-14 Course requirements (Total of 8 different courses Foundations in Experimental Biology 6 units MI 250* Frontiers in Microbiology & Immunology 1 unit MI 399 of Research 1 unit Spring MI 204 Innate Immunology 3 units MI 215 Principles of Biological Technologies 3

Sonnenburg, Justin L.


Load transfer in Christensen(®) TMJ in alloplastic total joint replacement for two different mouth apertures.  


This study analyses load transfer in the fossa component based on two numerical models of total temporomandibular joint (TMJ) implants for two mouth openings. The TMJ articulation is a very complex system with muscles, ligaments and cartilage. Until now, studies of TMJ implants have analysed only condylar behaviour. The finite element models were constructed based on CT scans of a cadaveric mandible and cranium, considering the bone geometry and position. The influence of five principal muscle actions was simulated for two mouth positions, 5 mm and 15 mm openings at the incisive tooth support. Strain distributions into the surrounding bone tissue were analysed in both models in the condyle and fossa components. The results demonstrate that in Christensen(®) TJR of the temporomandibular joint the fossa component is the more critical part, presenting more stress near the screw holes and contact regions with the cranium. The most critical region is around the first two screws and the least critical is in the condyle component. For the mandible condyle reconstructed with a Christensen(®) prosthesis, the 15 mm mouth opening was more critical, as compression was increased, but for the fossa component the most critical situation occurred with the 5 mm opening. The micromovements observed suggest that the number of screws could be reduced to increase osteointegration of screws in the mandible condyle. PMID:24954763

Ramos, António; Mesnard, Michel



Colours Core palette Colours Core palette APPLYING THE GUIDELINES  

E-print Network

) (web and screen) Bright aqua 3262 C81 M0 Y36 K0 r0 G192 B181 #00C0B5 Dark aqua 309 C99 M27 Y22 K80 r0 G THE GUIDELINES Colours Colour breakdowns for print and web Colour Pantone® CMYK RGB Hex (special) (professional and desktop printing) (web and screen) (web and screen) university red 187 C0 M91 Y72 K23 r171 G31 B45 #B01C2e

Bristol, University of


Perception of colour in unilateral tritanopia.  

PubMed Central

The unilateral tritanope described in the previous paper (Alpern, Kitahara & Krantz, 1983) was able to match every narrow-band light presented to his tritanopic eye with lights from a tristimulus colorimeter viewed in the adjacent field by the normal eye. In two regions of the spectrum (called isochromes) physically identical lights appeared identical to the observer's two eyes. One isochrome was close to 'blue' for the normal eye, the other was in the long-wave spectral region seen by the normal eye predominantly as 'red'. Between these isochromes the normal eye required less than spectral purity to match, dropping to near zero purity at 560-570 nm. A mixture of the two isochromes that appeared purple to the normal eye appeared neutral to the tritanopic eye. Hence dichoptic matches grossly violate Grassmann's additivity law. For the normal eye colour naming conformed to typical normal results. For the tritanopic eye the results were coherent with those found by dichoptic matching: the spectrum was divided into two regions by the achromatic neutral band. To the short-wave side, only the colour names 'blue' and 'white' were ever used. To the long-wave side the predominant colour names were 'red' and 'white' with some 'yellow'. Spectral lights appeared neither 'red-blue' nor greenish. Surrounding the test with an annulus either 430 nm, 650 nm, or a mixture of these, fails to induce any greenish appearance, although the achromatic band shifted in the expected directions. It is concluded that there must be exactly three functionally independent, essentially non-linear central codes for colour perception, and that these codes are different from those suggested in existing theories of colour perception. PMID:6603509

Alpern, M; Kitahara, K; Krantz, D H



Isolation and antisense suppression of flavonoid 3', 5'-hydroxylase modifies flower pigments and colour in cyclamen  

PubMed Central

Background Cyclamen is a popular and economically significant pot plant crop in several countries. Molecular breeding technologies provide opportunities to metabolically engineer the well-characterized flavonoid biosynthetic pathway for altered anthocyanin profile and hence the colour of the flower. Previously we reported on a genetic transformation system for cyclamen. Our aim in this study was to change pigment profiles and flower colours in cyclamen through the suppression of flavonoid 3', 5'-hydroxylase, an enzyme in the flavonoid pathway that plays a determining role in the colour of anthocyanin pigments. Results A full-length cDNA putatively identified as a F3'5'H (CpF3'5'H) was isolated from cyclamen flower tissue. Amino acid and phylogeny analyses indicated the CpF3'5'H encodes a F3'5'H enzyme. Two cultivars of minicyclamen were transformed via Agrobacterium tumefaciens with an antisense CpF3'5'H construct. Flowers of the transgenic lines showed modified colour and this correlated positively with the loss of endogenous F3'5'H transcript. Changes in observed colour were confirmed by colorimeter measurements, with an overall loss in intensity of colour (C) in the transgenic lines and a shift in hue from purple to red/pink in one cultivar. HPLC analysis showed that delphinidin-derived pigment levels were reduced in transgenic lines relative to control lines while the percentage of cyanidin-derived pigments increased. Total anthocyanin concentration was reduced up to 80% in some transgenic lines and a smaller increase in flavonol concentration was recorded. Differences were also seen in the ratio of flavonol types that accumulated. Conclusion To our knowledge this is the first report of genetic modification of the anthocyanin pathway in the commercially important species cyclamen. The effects of suppressing a key enzyme, F3'5'H, were wide ranging, extending from anthocyanins to other branches of the flavonoid pathway. The results illustrate the complexity involved in modifying a biosynthetic pathway with multiple branch points to different end products and provides important information for future flower colour modification experiments in cyclamen. PMID:20540805



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.



Regional difference in intestinal adaptation after total colectomy as judged by the changes of mucosal Na-K ATPase, cyclic AMP, and transmural potential difference.  


Intestinal adaptation and its regional difference after total colectomy were investigated in dogs by measuring mucosal Na-K ATPase, cyclic AMP, and transmural electric potential difference (PD). Twenty-four weeks after the total proctocolectomy, Na-K ATPase activity and PD increased significantly in all intestinal sites, whereas cyclic AMP showed no significant changes. The regional difference in the remaining intestine was examined in the jejunum, ileum, and interposed jejunum (neorectum). Na-K ATPase activity showed no significant regional difference, but the largest increase was found to occur in the ileum. PD also increased markedly in the ileum and there was significant difference between the ileum and other intestinal sites. These facts suggest that the increased active ion transport mediated by mucosal Na-K ATPase and transmural PD in the ileum is closely related to the intestinal adaptation occurring after total colectomy and indicates a greater potential of the ileum for adaptive compensation than either jejunum or neorectum. PMID:2839319

Nakahara, S; Itoh, H; Mibu, R; Ikeda, S; Nakayama, F



Phylogenetic analysis reveals a scattered distribution of autumn colours  

PubMed Central

Background and Aims Leaf colour in autumn is rarely considered informative for taxonomy, but there is now growing interest in the evolution of autumn colours and different hypotheses are debated. Research efforts are hindered by the lack of basic information: the phylogenetic distribution of autumn colours. It is not known when and how autumn colours evolved. Methods Data are reported on the autumn colours of 2368 tree species belonging to 400 genera of the temperate regions of the world, and an analysis is made of their phylogenetic relationships in order to reconstruct the evolutionary origin of red and yellow in autumn leaves. Key Results Red autumn colours are present in at least 290 species (70 genera), and evolved independently at least 25 times. Yellow is present independently from red in at least 378 species (97 genera) and evolved at least 28 times. Conclusions The phylogenetic reconstruction suggests that autumn colours have been acquired and lost many times during evolution. This scattered distribution could be explained by hypotheses involving some kind of coevolutionary interaction or by hypotheses that rely on the need for photoprotection. PMID:19126636

Archetti, Marco



Three-dimensional plasmonic stereoscopic prints in full colour.  


Metal nanostructures can be designed to scatter different colours depending on the polarization of the incident light. Such spectral control is attractive for applications such as high-density optical storage, but challenges remain in creating microprints with a single-layer architecture that simultaneously enables full-spectral and polarization control of the scattered light. Here we demonstrate independently tunable biaxial colour pixels composed of isolated nanoellipses or nanosquare dimers that can exhibit a full range of colours in reflection mode with linear polarization dependence. Effective polarization-sensitive full-colour prints are realized. With this, we encoded two colour images within the same area and further use this to achieve depth perception by realizing three-dimensional stereoscopic colour microprint. Coupled with the low cost and durability of aluminium as the functional material in our pixel design, such polarization-sensitive encoding can realize a wide spectrum of applications in colour displays, data storage and anti-counterfeiting technologies. PMID:25369035

Goh, Xiao Ming; Zheng, Yihan; Tan, Shawn J; Zhang, Lei; Kumar, Karthik; Qiu, Cheng-Wei; Yang, Joel K W



Introduction Colour-impaired vision, where certain colours cannot be  

E-print Network

these colours. Dark green, brown, orange, and dark red in the first row appear as almost indistinguishable olive, where he produces print graphics for daily publication and interactive web graphics. nvkelso

Jenny, Bernhard


Improving the Rainbow Attack by Reusing Colours  

NASA Astrophysics Data System (ADS)

Hashing or encrypting a key or a password is a vital part in most network security protocols. The most practical generic attack on such schemes is a time memory trade-off attack. Such an attack inverts any one-way function using a trade-off between memory and execution time. Existing techniques include the Hellman attack and the rainbow attack, where the latter uses different reduction functions ("colours") within a table.

Ågren, Martin; Johansson, Thomas; Hell, Martin


Floral scent emitted by white and coloured morphs in orchids.  


Polymorphism of floral signals, such as colour and odour, is widespread in flowering plants and often considered to be adaptive, reflecting various pollinator preferences for particular floral traits. Several authors have recently hypothesized that particular associations exist between floral colour and scent, which would result from shared biochemistry between these two floral traits. In this study, we compared the chemical composition of floral volatiles emitted by white- and purple-flowered morphs of three different orchid species, including two food-deceptive species (Orchis mascula and Orchis simia) and a food-rewarding species (Anacamptis coriophora fragrans). We found clear interspecific differences in floral odours. As expected from their pollination strategy, the two deceptive orchids showed high inter-individual variation of floral volatiles, whereas the food-rewarding A. c. fragrans showed low variation of floral scent. Floral volatiles did not differ overall between white- and coloured-flowered morphs in O. mascula and A. c. fragrans, while O. simia exhibited different volatile profiles between the two colour morphs. However, a detailed analysis restricted to benzenoid compounds (which are associated with the production of floral anthocyanin pigments) showed that white inflorescences emitted more volatiles of the shikimic pathway than coloured ones, both for O. mascula and O. simia. These results are consistent with the current hypothesis that shared biochemistry creates pleiotropic links between floral colour and scent. Whether intraspecific variation of floral signals actually affects pollinator attraction and influences the reproductive success of these orchids remains to be determined. PMID:24525191

Dormont, L; Delle-Vedove, R; Bessière, J-M; Schatz, B



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



Total Phenolic Contents and Antioxidant Activities of Different Extracts and Fractions from the Aerial Parts of Artemisia biennis Willd.  


Total phenolic contents (TPC) of five different extracts (petroleum ether, dichloromethane, ethyl acetate, ethanol and ethanol-water) of Artemisia biennis Willd were measured in this work. The antioxidant activity was investigated by three different methods: ?-carotene bleaching (BCB) test, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method and ferrous ion chelating (FIC) assay. Among all the extracts analyzed, the hydroethanolic extract exhibited a significantly higher phenolic content and antioxidant activity than other samples. Vacuum liquid chromatography of this extract yielded seven fractions (A to G) which were subjected to all aforementioned experiments. The highest total phenolic content and free radical scavenging activites were present in the same sample (Fraction D) but the only statistically significant correlation between TPC and EC50 values was observed for BCB. PMID:25237350

Hatami, Tayyebe; Emami, Sayyed Ahmad; Miraghaee, Sayyed Shahram; Mojarrab, Mahdi



Oxidation Efficiency of Different Oxidants of Persulfate Method Used to Determine Total Nitrogen and Phosphorus in Solutions  

Microsoft Academic Search

Its speed, safety, and convenience have made the persulfate oxidation method popular in recent years for determining total N and P in natural water, soil solution and soil extracts. However, the compositions of the oxidizing reagent (i.e., the concentrations of K2S2O8 and NaOH in oxidizing reagent) used by different researchers varied. In this study, a standard urea solution was used

Jianbin Zhou; Zhujun Chen; Shengxiu Li



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



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. PMID:24204864

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



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.



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



Distinct neural processes in grapheme-colour synaesthetes and semantic controls.  


In synaesthetes, stimulation of one sensory pathway provokes a sensory experience (e.g. a colour concurrent) in a different sensory modality or sub-modality. Results of synaesthetic Stroop and priming tests indicate that the perception of a colour concurrent interferes with the processing of a veridical colour in synaesthetes. We here examined the congruency between a stimulus' colour and the colour concurrent both in grapheme-colour synaesthetes and in non-synaesthetes trained on grapheme-colour associations. Electrophysiological (electroencephalogram) and behavioural measurements were collected during a priming task that included grapheme-grapheme and grapheme-colour patch pairs. To investigate covert bidirectional synaesthesia, an additional inverted colour patch-grapheme condition was included. Both groups of participants showed longer reaction time and more negative-going N300 and N400 event-related potential (ERP) components on incongruent trials. Whereas ERP effects in the non-synaesthetes were largely confined to the late cognitive components N300, P300 and N400, the synaesthetes also showed congruency-dependent modulation of the early sensory component N170. Our results suggest that early cognitive processes distinguish cross-modal synaesthetic perceptions from acquired associations. The involvement of both early- and late-stage cognitive components in bidirectional synaesthesia possibly indicates similar feature-binding mechanisms during processing of opposite flow directions of information, namely grapheme-colour and colour-grapheme. PMID:22928962

Niccolai, Valentina; Wascher, Edmund; Stoerig, Petra



The Colour of the Young Universe  

NASA Astrophysics Data System (ADS)

VLT study gives insight on the evolution of the star formation rate Summary An international team of astronomers [1] has determined the colour of the Universe when it was very young. While the Universe is now kind of beige, it was much bluer in the distant past , at a time when it was only 2,500 million years old. This is the outcome of an extensive and thorough analysis of more than 300 galaxies seen within a small southern sky area, the so-called Hubble Deep Field South. The main goal of this advanced study was to understand how the stellar content of the Universe was assembled and has changed over time. Dutch astronomer Marijn Franx , a team member from the Leiden Observatory (The Netherlands), explains: "The blue colour of the early Universe is caused by the predominantly blue light from young stars in the galaxies. The redder colour of the Universe today is caused by the relatively larger number of older, redder stars." The team leader, Gregory Rudnick from the Max-Planck Institut für Astrophysics (Garching, Germany) adds: "Since the total amount of light in the Universe in the past was about the same as today and a young blue star emits much more light than an old red star, there must have been significantly fewer stars in the young Universe than there is now. Our new findings imply that the majority of stars in the Universe were formed comparatively late, not so long before our Sun was born, at a moment when the Universe was around 7,000 million years old." These new results are based on unique data collected during more than 100 hours of observations with the ISAAC multi-mode instrument at ESO's Very Large Telescope (VLT), as part of a major research project, the Faint InfraRed Extragalactic Survey (FIRES) . The distances to the galaxies were estimated from their brightness in different optical near-infrared wavelength bands. PR Photo 34/03 : The Evolving Colour of the Universe . Observing the early Universe It is now well known that the Sun was formed some 4.5 billion years ago. But when did most of the other stars in our home Galaxy form? And what about stars in other galaxies? These are some of the key questions in present-day astronomy, but they can only be answered by means of observations with the world's largest telescopes. One way to address these issues is to observe the very young Universe directly - by looking back in time. For this, astronomers take advantage of the fact that light emitted by very distant galaxies travels a long time before reaching us. Thus, when astronomers look at such remote objects, they see them as they appeared long ago. Those remote galaxies are extremely faint, however, and these observations are therefore technically difficult. Another complication is that, due to the expansion of the Universe, light from those galaxies is shifted towards longer wavelengths [2], out of the optical wavelength range and into the infrared region. In order to study those early galaxies in some detail, astronomers must therefore use the largest ground-based telescopes, collecting their faint light during very long exposures. In addition they must use infrared-sensitive detectors. Telescopes as giant eyes The "Hubble Deep Field South (HDF-S)" is a very small portion of the sky in the southern constellation Tucanae ( "the Toucan" ). It was selected for very detailed studies with the Hubble Space Telescope (HST) and other powerful telescopes. Optical images of this field obtained by the HST represent a total exposure time of 140 hours. Many ground-based telescopes have also obtained images and spectra of objects in this sky area, in particular the ESO telescopes in Chile. A sky area of 2.5 x 2.5 arcmin 2 in the direction of HDF-S was observed in the context of a thorough study (the Faint InfraRed Extragalactic Survey; FIRES, see ESO PR 23/02 ). It is slightly larger than the field covered by the WFPC2 camera on the HST, but still 100 times smaller than the area subtended by the full moon. Whenever this field was visible from the ESO Paranal Observatory and th



Colour naturalness metric for evaluating image quality of mobile displays  

NASA Astrophysics Data System (ADS)

A series of psychophysical experiments using categorical judgment method was carried out to develop a colour naturalness metric (CNM) for evaluating image quality of mobile displays. These experiments included colour naturalness judgment and image-quality difference judgment. Through the former one, CNMs were trained and the latter experiment tested the metrics. Two types of CNMs were newly proposed: nonlinearly decaying CNM and linearly decaying CNM. In the CNMs, it was assumed that one familiar object in an image played a critical role to judge the colour naturalness of the whole image. Through a performance comparison between objects' models, one critical object in a scene was selected and with the critical object's model, the whole scene's colour naturalness was predicted.

Yoo, Jang Jin; Cui, Guihua; Luo, M. Ronnier



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


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. PMID:23768150

Rich, Anina N; Karstoft, Karen-Inge



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



Fixed- vs mobile-bearing total knee arthroplasty: does it make a difference?--a prospective randomized study.  


The purpose of this prospective, randomized study was to compare the early clinical and functional results of primary total knee arthroplasty using a fixed-bearing (FB) and a rotating-platform (RP) prosthesis. Outcomes including range of motion (ROM), Knee Society Score, Western Ontario MacMaster (WOMAC), and Short Form-36 (SF-36) were measured preoperatively and at 6 weeks, 3 months, 6 months, 1 year, and 2 years. Radiographic analysis was performed. There were 72 FB and 68 RP knees. The RP group had a greater ROM at 6 weeks and 1 year. This difference was not statistically significant at 2 years. There were no differences in the ROM at any other period. There were no significant differences in Knee Society Score, Short Form-36, or Western Ontario MacMaster scores at any period. No clinically significant differences were noted in the radiographic analysis. The use of a FB or RP design did not affect the early functional outcomes after total knee arthroplasty. PMID:19553072

Harrington, Melvyn A; Hopkinson, William J; Hsu, Patricia; Manion, Leslie



Synthetic food colours in saffron solutions, saffron rice and saffron chicken from restaurants in Tehran, Iran.  


Saffron solutions, saffron rice and saffron chicken samples were considered for synthetic colours as additives, which are forbidden according to Iranian national standards. Samples were taken from restaurants of three locations and analysed by high-performance liquid chromatography. Of the total 573 samples, 52% were positive for at least one colour. The most prevalent colours were Tartrazine, Quinoline Yellow and Sunset Yellow, with 44%, 9.1% and 8.4% of the samples testing positive for these colours, respectively. Carmoisine and Ponceau were both detected only in 0.5% of the positive samples and found only in saffron solution. In conclusion, synthetic food colours, especially Tartrazine should be regarded as a potential risk in saffron and its related food. Therefore, new attempts for food safety and quality should be undertaken to eliminate the use of these colours in restaurants. PMID:25116149

Moradi-Khatoonabadi, Zhila; Amirpour, Mansooreh; AkbariAzam, Maryam



Influence of grape variety, vine system and enological treatments on the colour stability of young red wines  

Microsoft Academic Search

The short shelf life of wines from the Northwest of the Iberian Peninsula requires careful control of their colour characteristics. In this work, we studied such characteristics in wines made from three different Vitis vinifera red grape varieties grown in northwestern Spain (viz. Sousón, Mencía and Brancellao, in sequence of decreasing colour intensity). The colour of the resulting wines was

C. Pérez-Lamela; M. S. García-Falcón; J. Simal-Gándara; I. Orriols-Fernández



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

NASA Astrophysics Data System (ADS)

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.

Papiorek, Sarah; Rohde, Katja; Lunau, Klaus



Colour cues facilitate learning flower refill schedules in wild hummingbirds.  


Free-living hummingbirds can learn the refill schedules of individual experimental flowers but little is known about what information they use to do this. Colour cues, in particular, may be important to hummingbirds when learning about rewarded flower properties. We investigated, therefore, whether colour cues facilitated the learning of flower refill schedules in wild, free-living rufous hummingbirds (Selasphorus rufus). In the Cued condition, we presented birds with an array of six flowers, three of one colour, each of which were refilled 10min after being emptied by the bird and three of a different colour, which were refilled 20min after being emptied. In the Uncued condition we presented birds with six flowers of the same colour, three of which were refilled after 10min and three of which were refilled after 20min as for the birds in the Cued condition. In the second part of the experiment, we moved the array 2m and changed the shape of the array. Across both phases, birds in the Cued condition learned to discriminate between 10 and 20-min flowers more quickly than did the birds in the Uncued condition. The Cued birds were also better at discriminating between the two distinct refill intervals. Colour cues can, therefore, facilitate learning the refill schedules of experimental flowers in these birds. This article is part of a Special Issue entitled: Cognition in the wild. PMID:25234604

Samuels, Michael; Hurly, T Andrew; Healy, Susan D



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.



Aqueous two-phase based on ionic liquid liquid-liquid microextraction for simultaneous determination of five synthetic food colourants in different food samples by high-performance liquid chromatography.  


A rapid and effective method of aqueous two-phase systems based on ionic liquid microextraction for the simultaneous determination of five synthetic food colourants (tartrazine, sunset yellow, amaranth, ponceau 4R and brilliant blue) in food samples was established. High-performance liquid chromatography coupled with an ultraviolet detector of variable wavelength was used for the determinations. 1-alkyl-3-methylimidazolium bromide was selected as the extraction reagent. The extraction efficiency of the five colourants in the proposed system is influenced by the types of salts, concentrations of salt and [CnMIM]Br, as well as the extracting time. Under the optimal conditions, the extraction efficiencies for these five colourants were above 95%. The phase behaviours of aqueous two-phase system and extraction mechanism were investigated by UV-vis spectroscopy. This method was applied to the analysis of the five colourants in real food samples with the detection limit of 0.051-0.074ng/mL. Good spiked recoveries from 93.2% to 98.9% were obtained. PMID:25529695

Sha, Ou; Zhu, Xiashi; Feng, Yanli; Ma, Weixing



Synaesthesia in a logographic language: the colouring of Chinese characters and Pinyin/Bopomo spellings.  


Studies of linguistic synaesthesias in English have shown a range of fine-grained language mechanisms governing the associations between colours on the one hand, and graphemes, phonemes and words on the other. However, virtually nothing is known about how synaesthetic colouring might operate in non-alphabetic systems. The current study shows how synaesthetic speakers of Mandarin Chinese come to colour the logographic units of their language. Both native and non-native Chinese speakers experienced synaesthetic colours for characters, and for words spelled in the Chinese spelling systems of Pinyin and Bopomo. We assessed the influences of lexical tone and Pinyin/Bopomo spelling and showed that synaesthetic colours are assigned to Chinese words in a non-random fashion. Our data show that Chinese-speaking synaesthetes with very different native languages can exhibit both differences and similarities in the ways in which they come to colour their Chinese words. PMID:21684180

Simner, Julia; Hung, Wan-Yu; Shillcock, Richard



Grey-scale and colour Doppler ultrasound versus Magnetic resonance imaging for the prenatal diagnosis of placenta accreta.  


Abstract Objective: to assess the effectiveness of grey-scale and colour Doppler ultrasound (US) versus magnetic resonance imaging (MRI) for the prenatal diagnosis of placenta accreta. Methods: A prospective observational study including a total of 74 patients with placenta previa and previous uterine scar (n = 74). Gray-scale and colour Doppler US was done followed by MRI by different observers to diagnose adherent placenta. Test validity of of US and MRI were calculated. Maternal morbidity and mortality were also assessed. Results: 53 patients confirmed to have placenta accreta at operation. The overall sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of US was 94.34 %, 91.67 %, 96.15% and 88 % compared to 96.08 %, 87.50 %, 94.23 % and 91.3% for MRI respectively. The most relevant US sign was turbulent blood flow by colour Doppler while dark intra-placental band was the most sensitive MRI sign. Venous thromboembolism (1.3%), bladder injury (29.7%), ureteric injury (18.9%), post-operative fever (10.8%), Admission to ICU (50%) and re-operation (31.1%). Conclusion: Placenta accreta can be successfully diagnosed by grey scale and colour Doppler ultrasound. MRI would be more likely suggested for either posteriorly or laterally situated placenta previa in order to exclude placental invasion. PMID:25434644

Rezk, Mohamed; Shawky, Mohamed



Ecological genomics in full colour.  


Colour patterns in animals have long offered an opportunity to observe adaptive traits in natural populations. Colour plays myriad roles in interactions within and among species, from reproductive signalling to predator avoidance, leading to multiple targets of natural and sexual selection and opportunities for diversification. Understanding the genetic and developmental underpinnings of variation in colour promises a fuller understanding of these evolutionary processes, but the path to unravelling these connections can be arduous. The advent of genomic techniques suitable for nonmodel organisms is now beginning to light the way. Two new studies in this issue of Molecular Ecology use genomic sequencing of laboratory crosses to map colour traits in cichlid fishes, a remarkably diverse group in which coloration has played a major role in diversification. They illustrate how genomic approaches, specifically RAD sequencing, can rapidly identify both simple and more complex genetic variation underlying ecologically important traits. In the first, Henning et al. () detect a single locus that appears to control in a Mendelian fashion the presence of horizontal stripes, a trait that has evolved in numerous cichlid lineages. In the second, Albertson et al. () identify several genes and epistatic interactions affecting multiple colour traits, as well as a novel metric describing integration across colour traits. Albertson et al. () go further, by quantifying differential expression of parental alleles at a candidate locus and by relating differentiation among natural populations at mapped loci to trait divergence. Herein lies the promise of ecological genomics - efficiently integrating genetic mapping of phenotypes with population genomic data to both identify functional genes and unravel their evolutionary history. These studies offer guidance on how genomic techniques can be tailored to a research question or study system, and they also add to the growing body of empirical examples addressing basic questions about how ecologically important traits evolve in natural populations. PMID:25330852

Hohenlohe, Paul A



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.



Differences in the fretting corrosion of metal-metal and ceramic-metal modular junctions of total hip replacements.  


The use of modular interlocking components is a central design feature of total joint replacements. In this investigation we hypothesized that clinically available ceramic-metal modular connections used in total hip arthroplasty release more metal through fretting corrosion than traditional metal-metal modular connections. This was investigated using an in vitro comparison of ceramic (zirconia, ZrO2) and metal (Co-alloy) femoral-head fretting upon Co-alloy stem components. In vitro fretting corrosion testing consisted of potentiodynamic monitoring and analysis of metal release from zirconia and Co-alloy 28 mm femoral heads with similar surface roughnesses (Ra=0.46 microm) on identical Co-alloy stems at 2.2 kN for 1x10(6) cycles at 2 Hz. In contrast to our original hypothesis, we found greater metal release (approximately 11-fold increase in Co and 3-fold increase in Cr) and potentiodynamic fretting of metal-metal modular junctions when compared to ceramic-metal. Potentiodynamic testing demonstrated that lower initial voltages (-266<153 mV), greater maximum voltage changes (116>56 mV, p<0.05, t-test) and voltage variability (3>0.5 mV, p<0.05, t-test) were associated with the open circuit potentials of Co-alloy on Co-alloy junctions when compared to zirconia on Co-alloy junctions. In this study of a single total hip replacement stem and head design, zirconia heads mated with Co-alloy stems produced less fretting than Co-alloy heads mated with Co-alloy stems. Although further studies are necessary with a variety of implant designs and under different experimental conditions, the evidence presented here should, in part, alleviate concerns of increases in fretting corrosion at modular junctions of ceramic-metal coupled components. PMID:15013082

Hallab, Nadim James; Messina, Carlo; Skipor, Anastasia; Jacobs, Joshua J



Texture Variations Suppress Suprathreshold Brightness and Colour Variations  

PubMed Central

Discriminating material changes from illumination changes is a key function of early vision. Luminance cues are ambiguous in this regard, but can be disambiguated by co-incident changes in colour and texture. Thus, colour and texture are likely to be given greater prominence than luminance for object segmentation, and better segmentation should in turn produce stronger grouping. We sought to measure the relative strengths of combined luminance, colour and texture contrast using a suprathreshhold, psychophysical grouping task. Stimuli comprised diagonal grids of circular patches bordered by a thin black line and contained combinations of luminance decrements with either violet, red, or texture increments. There were two tasks. In the Separate task the different cues were presented separately in a two-interval design, and participants indicated which interval contained the stronger orientation structure. In the Combined task the cues were combined to produce competing orientation structure in a single image. Participants had to indicate which orientation, and therefore which cue was dominant. Thus we established the relative grouping strength of each cue pair presented separately, and compared this to their relative grouping strength when combined. In this way we observed suprathreshold interactions between cues and were able to assess cue dominance at ecologically relevant signal levels. Participants required significantly more luminance and colour compared to texture contrast in the Combined compared to Separate conditions (contrast ratios differed by about 0.1 log units), showing that suprathreshold texture dominates colour and luminance when the different cues are presented in combination. PMID:25502555

Schofield, Andrew J.; Kingdom, Frederick A. A.



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



Cross-modal associations in synaesthesia: Vowel colours in the ear of the beholder  

PubMed Central

Human speech conveys many forms of information, but for some exceptional individuals (synaesthetes), listening to speech sounds can automatically induce visual percepts such as colours. In this experiment, grapheme–colour synaesthetes and controls were asked to assign colours, or shades of grey, to different vowel sounds. We then investigated whether the acoustic content of these vowel sounds influenced participants' colour and grey-shade choices. We found that both colour and grey-shade associations varied systematically with vowel changes. The colour effect was significant for both participant groups, but significantly stronger and more consistent for synaesthetes. Because not all vowel sounds that we used are “translatable” into graphemes, we conclude that acoustic–phonetic influences co-exist with established graphemic influences in the cross-modal correspondences of both synaesthetes and non-synaesthetes. PMID:25469218

Moos, Anja; Smith, Rachel; Miller, Sam R.; Simmons, David R.



Cross-modal associations in synaesthesia: Vowel colours in the ear of the beholder.  


Human speech conveys many forms of information, but for some exceptional individuals (synaesthetes), listening to speech sounds can automatically induce visual percepts such as colours. In this experiment, grapheme-colour synaesthetes and controls were asked to assign colours, or shades of grey, to different vowel sounds. We then investigated whether the acoustic content of these vowel sounds influenced participants' colour and grey-shade choices. We found that both colour and grey-shade associations varied systematically with vowel changes. The colour effect was significant for both participant groups, but significantly stronger and more consistent for synaesthetes. Because not all vowel sounds that we used are "translatable" into graphemes, we conclude that acoustic-phonetic influences co-exist with established graphemic influences in the cross-modal correspondences of both synaesthetes and non-synaesthetes. PMID:25469218

Moos, Anja; Smith, Rachel; Miller, Sam R; Simmons, David R



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. PMID:23110638



Removal of total and antibiotic resistant bacteria in advanced wastewater treatment by ozonation in combination with different filtering techniques.  


Elimination of bacteria by ozonation in combination with charcoal or slow sand filtration for advanced sewage treatment to improve the quality of treated sewage and to reduce the potential risk for human health of receiving surface waters was investigated in pilot scale at the sewage treatment plant Eriskirch, Baden-Wuerttemberg/Germany. To determine the elimination of sewage bacteria, inflowing and leaving wastewater of different treatment processes was analysed in a culture-based approach for its content of Escherichia coli, enterococci and staphylococci and their resistance against selected antibiotics over a period of 17 month. For enterococci, single species and their antibiotic resistances were identified. In comparison to the established flocculation filtration at Eriskirch, ozonation plus charcoal or sand filtration (pilot-scale) reduced the concentrations of total and antibiotic resistant E. coli, enterococci and staphylococci. However, antibiotic resistant E. coli and staphylococci apparently survived ozone treatment better than antibiotic sensitive strains. Neither vancomycin resistant enterococci nor methicillin resistant Staphylococcus aureus (MRSA) were detected. The decreased percentage of antibiotic resistant enterococci after ozonation may be explained by a different ozone sensitivity of species: Enterococcus faecium and Enterococcus faecalis, which determined the resistance-level, seemed to be more sensitive for ozone than other Enterococcus-species. Overall, ozonation followed by charcoal or sand filtration led to 0.8-1.1 log-units less total and antibiotic resistant E. coli, enterococci and staphylococci, as compared to the respective concentrations in treated sewage by only flocculation filtration. Thus, advanced wastewater treatment by ozonation plus charcoal or sand filtration after common sewage treatment is an effective tool for further elimination of microorganisms from sewage before discharge in surface waters. PMID:25497174

Lüddeke, Frauke; Heß, Stefanie; Gallert, Claudia; Winter, Josef; Güde, Hans; Löffler, Herbert



Quark interactions and colour chemistry  

Microsoft Academic Search

The interaction between quarks, according to the current theory of quantum chromo-dynamics, is formally rather similar to the electromagnetic interaction between electrons and nucleons, both being governed by locally gauge-invariant field theories. It is tempting therefore to discuss the spectroscopy of hadrons, which are quark composites bound by colour forces, in the same language as the spectroscopy of atoms and

Chan Hong-Mo



Addition table of colours: additive and subtractive mixtures described using a single reasoning model  

NASA Astrophysics Data System (ADS)

Students’ misconceptions concerning colour phenomena and the apparent complexity of the underlying concepts—due to the different domains of knowledge involved—make its teaching very difficult. We have developed and tested a teaching device, the addition table of colours (ATC), that encompasses additive and subtractive mixtures in a single conceptual model and presents colour as a perceptual response to light. The ATC was used as the focus of an introduction to colour phenomena in a middle class setting, showing significant educational gains among the students.

Mota, A. R.; Lopes dos Santos, J. M. B.



The fiddler crab Uca mjoebergi uses colour vision in mate choice  

PubMed Central

Although the role of colour in mate choice is well known, few tests of colour vision have been based on mating behaviour. Females of the fiddler crab Uca mjoebergi have recently been shown to use claw coloration to recognize conspecific males. In this study I demonstrate that the females use colour vision for this task; preferentially approaching yellow claws over grey claws regardless of their intensity while failing to discriminate between yellow claws differing in intensity. This is one of only a handful of studies confirming the involvement of colour vision in mate choice and the first conclusive evidence in fiddler crabs. PMID:17848366

Detto, Tanya



The effect of stress and stress hormones on dynamic colour-change in a sexually dichromatic Australian frog.  


Rapid colour changes in vertebrates have fascinated biologists for centuries, herein we demonstrate dynamic colour change in an anuran amphibian, the stony creek frog (Litoria wilcoxii), which turns from brown to bright (lemon) yellow during amplexus. We show this by comparing the colour of baseline (unpaired males) and amplecting (paired) males. We also investigate the possible role of stress and stress hormones on this colour change. Frogs were subjected to four different levels of stressors (handling, toe-clipping, saline injection and adrenocorticotropic hormone [ACTH] injection) and the colour change was measured using digital photography. A comparison of baseline colour and stress hormone (corticosterone) levels was also conducted to give further insight to this topic. From the images, the Red Blue Green (RGB) colour values were calculated, and a principal components analysis (PCA) was used to create a single colour metric (the major axis) as an index of colour in the visible spectrum. A moderate stressor (toe-clipping) led to a significant change in colour (within 10 min) similar to that of amplecting males. Surprisingly, neither a mild stressor (handling and saline injection) nor the maximum stressor (handling and ACTH injection) led to a lightening response. This study confirms that the dynamic male colour change in this species in response to medium stressors adds new knowledge to the understanding of the functional mechanisms of dynamic colour change in amphibians. PMID:23507571

Kindermann, Christina; Narayan, Edward J; Wild, Francis; Wild, Clyde H; Hero, Jean-Marc



Correlations between the neurobiology of colour vision and the psycholinguistics of colour naming  

Microsoft Academic Search

Summary Neurobiological experiments demonstrate that colour sensation is perceived by the brain by processes which, in principle, follow the opponent colour pairs scheme proposed by Hering in 1874. Tests on colour naming in various European, Asian and Central American languages have shown that the opponent scheme is also reflected in psycholinguistics. The linguistic evolution of colour terms proposed by Berlin

Heinrich Zollinger; Roman Jakobson



Search for colour singlet and colour reconnection effects in hadronic Z decays at LEP  

NASA Astrophysics Data System (ADS)

A search is performed in symmetric 3-jet hadronic Z-decay events for evidence of colour singlet production or colour reconnection effects. Asymmetries in the angular separation of particles are found to be sensitive indicators of such effects. Upper limits on the level of colour singlet production or of colour reconnection effects are established for a variety of models.

Achard, P.; Adriani, O.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M. G.; Anderhub, H.; Andreev, V. P.; Anselmo, F.; Arefiev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay, L.; Baldew, S. V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillère, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.; Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J. J.; Blyth, S. C.; Bobbink, G. J.; Böhm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J. G.; Brochu, F.; Burger, J. D.; Burger, W. J.; Cai, X. D.; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Chamizo, M.; Chang, Y. H.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G. M.; Chen, H. F.; Chen, H. S.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; de la Cruz, B.; Cucciarelli, S.; van Dalen, J. A.; de Asmundis, R.; Déglon, P.; Debreczeni, J.; Degré, A.; Dehmelt, K.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M. T.; Duchesneau, D.; Duda, M.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.; Engler, A.; Eppling, F. J.; Extermann, P.; Falagan, M. A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fesefeldt, H.; Fiandrini, E.; Field, J. H.; Filthaut, F.; Fisher, P. H.; Fisher, W.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Yu.; Ganguli, S. N.; Garcia-Abia, P.; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z. F.; Grenier, G.; Grimm, O.; Gruenewald, M. W.; Guida, M.; van Gulik, R.; Gupta, V. K.; Gurtu, A.; Gutay, L. J.; Haas, D.; Hatzifotiadou, D.; Hebbeker, T.; Hervé, A.; Hirschfelder, J.; Hofer, H.; Hohlmann, M.; Holzner, G.; Hou, S. R.; Hu, Y.; Jin, B. N.; Jones, L. W.; de Jong, P.; Josa-Mutuberr?´a, I.; Käfer, D.; Kaur, M.; Kienzle-Focacci, M. N.; Kim, J. K.; Kirkby, J.; Kittel, W.; Klimentov, A.; König, A. C.; Kopal, M.; Koutsenko, V.; Kräber, M.; Kraemer, R. W.; Krüger, A.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Le Goff, J. M.; Leiste, R.; Levtchenko, M.; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C. H.; Lin, W. T.; Linde, F. L.; Lista, L.; Liu, Z. A.; Lohmann, W.; Longo, E.; Lu, Y. S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W. G.; Malgeri, L.; Malinin, A.; Maña, C.; Mans, J.; Martin, J. P.; Marzano, F.; Mazumdar, K.; McNeil, R. R.; Mele, S.; Merola, L.; Meschini, M.; Metzger, W. J.; Mihul, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G. B.; Muanza, G. S.; Muijs, A. J. M.; Musicar, B.; Musy, M.; Nagy, S.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Nowak, H.; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.; Passaleva, G.; Patricelli, S.; Paul, T.; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.; Pioppi, M.; Piroué, P. A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofiev, D.; Quartieri, J.; Rahal-Callot, G.; Rahaman, M. A.; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P. G.; Ranieri, R.; Raspereza, A.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Riemann, S.; Riles, K.; Roe, B. P.; Romero, L.; Rosca, A.; Rosier-Lees, S.; Roth, S.; Rosenbleck, C.; Rubio, J. A.; Ruggiero, G.; Rykaczewski, H.; Sakharov, A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schäfer, C.; Schegelsky, V.; Schopper, H.; Schotanus, D. J.; Sciacca, C.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.; Steuer, M.; Stickland, D. P.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L. Z.; Sushkov, S.; Suter, H.; Swain, J. D.; Szillasi, Z.; Tang, X. W.; Tarjan, P.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, C.; Ting, Samuel C. C.; Ting, S. M.; Tonwar, S. C.; Tóth, J.; Tully, C.; Tung, K. L.; Ulbricht, J.; Valente, E.; Van de Walle, R. T.; Vasquez, R.; Veszpremi, V.; Vesztergombi, G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobiev, I.; Vorobyov, A. A.; Wadhwa, M.; Wang, Q.; Wang, X. L.; Wang, Z. M.; Weber, M.; Wienemann, P.; Wilkens, H.; Wynhoff, S.; Xia, L.; Xu, Z. Z.; Yamamoto, J.; Yang, B. Z.; Yang, C. G.; Yang, H. J.; Yang, M.; Yeh, S. C.; Zalite, An.; Zalite, Yu.; Zhang, Z. P.; Zhao, J.



Summing large- towers in colour flow evolution  

NASA Astrophysics Data System (ADS)

We consider soft-gluon evolution in the colour flow basis. We give explicit expressions for the colour structure of the (one-loop) soft anomalous dimension matrix for an arbitrary number of partons, and we show how the successive exponentiation of classes of large- contributions can be achieved to provide a systematic expansion of the evolution in terms of colour-suppressed contributions.

Plätzer, Simon



Polymorphism and Adaptation of Primate Colour Vision  

E-print Network

Chapter 13 Polymorphism and Adaptation of Primate Colour Vision Amanda D. Melin, Chihiro Hiramatsu levels. Primates have evolved a unique ability for trichromatic colour vision from a dichromatic in extensive colour vision variability in New World monkeys, where trichromats and dichromats are found

Fedigan, Linda M.


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



Genetics of novel corolla colours in periwinkle  

Microsoft Academic Search

Inheritance of a novel corolla colour in periwinkle [Catharanthus roseus (L) G. Don], viz. magenta, was studied by crossing an accession MJ, possessing this corolla colour, with cultivar Nirmal, possessing white corolla. The accession MJ was also crossed with another accession OR, possessing another novel corolla colour, viz. orange-red, to determine the relationship between genes governing magenta corolla and orange-red

R. N. Kulkarni; K. Baskaran; Y. Sreevalli



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



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



Uncertainty analysis of total phosphorus spatial-temporal variations in the Yangtze River Estuary using different interpolation methods.  


Interpolation processes and results are generally accompanied by uncertainty which affects the spatial and temporal properties of pollutants. Based on the 4 period sample data of total phosphorus (TP) collected from the Yangtze River Estuary (YRE) in 2010 and 2011, the uncertainty of spatial-temporal variation was analyzed with interpolation methods of inverse distance weighted (IDW), local polynomial interpolation (LPI), ordinary kriging (OK) and disjunctive kriging (DK). The root mean square errors (RMSE) and the mean relative errors (MRE) were used to analyze the accuracy of different interpolation methods. The results showed that the uncertainty of DK was the lowest and the uncertainty of LPI was the highest among the 4 methods. The subtraction results between different interpolation methods showed that there was some distinct area of value in the disparate interval (not in [-0.05, 0.05] (mg/L)) in the 4 seasonal results, which was mainly distributed in the boundary region and around some sample sites. Both standard deviation (SD) and coefficient of variance (CV) in August 2010 were the highest in the 4 seasons and annual mean. The uncertainty may be caused by choice of interpolation methods, spatial data discrepancy and the lack of sample data. PMID:25113104

Liu, Ruimin; Chen, Yaxin; Sun, Chengchun; Zhang, Peipei; Wang, Jiawei; Yu, Wenwen; Shen, Zhenyao



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.



An R2R3 MYB transcription factor determines red petal colour in an Actinidia (kiwifruit) hybrid population  

PubMed Central

Background Red colour in kiwifruit results from the presence of anthocyanin pigments. Their expression, however, is complex, and varies among genotypes, species, tissues and environments. An understanding of the biosynthesis, physiology and genetics of the anthocyanins involved, and the control of their expression in different tissues, is required. A complex, the MBW complex, consisting of R2R3-MYB and bHLH transcription factors together with a WD-repeat protein, activates anthocyanin 3-O-galactosyltransferase (F3GT1) to produce anthocyanins. We examined the expression and genetic control of anthocyanins in flowers of Actinidia hybrid families segregating for red and white petal colour. Results Four inter-related backcross families between Actinidia chinensis Planch. var. chinensis and Actinidia eriantha Benth. were identified that segregated 1:1 for red or white petal colour. Flower pigments consisted of five known anthocyanins (two delphinidin-based and three cyanidin-based) and three unknowns. Intensity and hue differed in red petals from pale pink to deep magenta, and while intensity of colour increased with total concentration of anthocyanin, no association was found between any particular anthocyanin data and hue. Real time qPCR demonstrated that an R2R3 MYB, MYB110a, was expressed at significant levels in red-petalled progeny, but not in individuals with white petals. A microsatellite marker was developed that identified alleles that segregated with red petal colour, but not with ovary, stamen filament, or fruit flesh colour in these families. The marker mapped to chromosome 10 in Actinidia. The white petal phenotype was complemented by syringing Agrobacterium tumefaciens carrying Actinidia 35S::MYB110a into the petal tissue. Red pigments developed in white petals both with, and without, co-transformation with Actinidia bHLH partners. MYB110a was shown to directly activate Actinidia F3GT1 in transient assays. Conclusions The transcription factor, MYB110a, regulates anthocyanin production in petals in this hybrid population, but not in other flower tissues or mature fruit. The identification of delphinidin-based anthocyanins in these flowers provides candidates for colour enhancement in novel fruits. PMID:23324587



On the colouring of spheres embedded in R^n  

NASA Astrophysics Data System (ADS)

The work concerns the well-known problem of identifying the chromatic number \\chi( R^n) of the space R^n, that is, finding the minimal number of colours required to colour all points of the space in such a way that any two points at distance one from each other have different colours. A new quantity generalising the chromatic number is introduced in the paper, namely, the speckledness of a subset in a fixed metric space. A series of lower bounds for the speckledness of spheres is derived. These bounds are used to obtain general results lifting lower bounds for the chromatic number of a space to higher dimensions, generalising the well-known 'Moser-Raisky spindle'. As a corollary of these results, the best known lower bound for the chromatic number \\chi( R^{12})\\ge 27 is obtained, and furthermore, the known bound \\chi( R^4)\\ge 7 is reproved in several different ways. Bibliography: 23 titles.

Kupavskii, Andrei B.



[Inherited colour vision deficiencies--from Dalton to molecular genetics].  


In recent years, great advances have been made in our understanding of the molecular basis of colour vision defects, as well as of the patterns of genetic variation in individuals with normal colour vision. Molecular genetic analyses have explained the diversity of types and degrees of severity in colour vision anomalies, their frequencies, pronounced individual variations in test results, etc. New techniques have even enabled the determination of John Dalton's real colour vision defect, 150 years after his death. Inherited colour vision deficiencies most often result from the mutations of genes that encode cone opsins. Cone opsin genes are linked to chromosomes 7 (the S or "blue" gene) and X (the L or "red" gene and the M or "green" gene). The L and M genes are located on the q arm of the X chromosome in a head-to-tail array, composed of 2 to 6 (typically 3) genes--a single L is followed by one or more M genes. Only the first two genes of the array are expressed and contribute to the colour vision phenotype. The high degree of homology (96%) between the L and M genes predisposes them to unequal recombination, leading to gene deletion or the formation of hybrid genes (comprising portions of both the L and M genes), explaining the majority of the common red-green colour vision deficiencies. The severity of any deficiency is influenced by the difference in spectral sensitivity between the opsins encoded by the first two genes of the array. A rare defect, S monochromacy, is caused either by the deletion of the regulatory region of the array or by mutations that inactivate the L and M genes. Most recent research concerns the molecular basis of complete achromatopsia, a rare disorder that involves the complete loss of all cone function. This is not caused by mutations in opsin genes, but in other genes that encode cone-specific proteins, e.g. channel proteins and transducin. PMID:16758855

Cvetkovi?, Dragana; Cvetkovi?, Dobrosav



A candidate-gene association study for berry colour and anthocyanin content in Vitis vinifera L.  


Anthocyanin content is a trait of major interest in Vitis vinifera L. These compounds affect grape and wine quality, and have beneficial effects on human health. A candidate-gene approach was used to identify genetic variants associated with anthocyanin content in grape berries. A total of 445 polymorphisms were identified in 5 genes encoding transcription factors and 10 genes involved in either the biosynthetic pathway or transport of anthocyanins. A total of 124 SNPs were selected to examine association with a wide range of phenotypes based on RP-HPLC analysis and visual characterization. The phenotypes were total skin anthocyanin (TSA) concentration but also specific types of anthocyanins and relative abundance. The visual assessment was based on OIV (Organisation Internationale de la Vigne et du Vin) descriptors for berry and skin colour. The genes encoding the transcription factors MYB11, MYBCC and MYC(B) were significantly associated with TSA concentration. UFGT and MRP were associated with several different types of anthocyanins. Skin and pulp colour were associated with nine genes (MYB11, MYBCC, MYC(B), UFGT, MRP, DFR, LDOX, CHI and GST). Pulp colour was associated with a similar group of 11 genes (MYB11, MYBCC, MYC(B), MYC(A), UFGT, MRP, GST, DFR, LDOX, CHI and CHS(A)). Statistical interactions were observed between SNPs within the transcription factors MYB11, MYBCC and MYC(B). SNPs within LDOX interacted with MYB11 and MYC(B), while SNPs within CHI interacted with MYB11 only. Together, these findings suggest the involvement of these genes in anthocyanin content and on the regulation of anthocyanin biosynthesis. This work forms a benchmark for replication and functional studies. PMID:23029369

Cardoso, Silvana; Lau, Winston; Eiras Dias, José; Fevereiro, Pedro; Maniatis, Nikolas



A frameshift mutation in the melanophilin gene causes the dilute coat colour in rabbit (Oryctolagus cuniculus) breeds.  


In rabbit, the dilute locus is determined by a recessive mutated allele (d) that causes the dilution of both eumelanic and pheomelanic pigmentations. In mice, similar phenotypes are determined by mutations in the myosin VA, Rab27a and melanophilin (MLPH) genes. In this study, we investigated the rabbit MLPH gene and showed that a mutation in this gene appears responsible for the dilute coat colour in this species. Checkered Giant F1 families segregating for black and grey (diluted or blue) coat colour were first genotyped for a complex indel in intron 1 of the MLPH gene that was completely associated with the coat colour phenotype (? = 0.00; LOD = 4.82). Then, we sequenced 6357 bp of the MLPH gene in 18 rabbits of different coat colours, including blue animals. A total of 165 polymorphisms were identified: 137 were in non-coding regions and 28 were in coding exons. One of them was a frameshift deletion in exon 5. Genotyping the half-sib families confirmed the complete cosegregation of this mutation with the blue coat colour. The mutation was analysed in 198 rabbits of 23 breeds. All Blue Vienna and all other blue/grey/ash rabbits in other breeds (Californian, Castor Rex, Checkered Giant, English Spot, Fairy Marburg and Fairy Pearly) were homozygous for this deletion. The identification of MLPH as the responsible gene for the dilute locus in rabbit provides a natural animal model for human Griscelli syndrome type 3 and a new mutant to study the role of this gene on pigmentation. PMID:24320228

Fontanesi, L; Scotti, E; Allain, D; Dall'olio, S



Implant based differences in adverse local tissue reaction in failed total hip arthroplasties: a morphological and immunohistochemical study  

PubMed Central

Background Adverse local tissue reaction (ALTR) is characterized by periprosthetic soft tissue inflammation composed of a mixed inflammatory cell infiltrate, extensive soft tissue necrosis, and vascular changes. Multiple hip implant classes have been reported to result in ALTR, and clinical differences may represent variation in the soft tissue response at the cellular and tissue levels. The purpose of this study was to describe similarities and differences in periprosthetic tissue structure, organization, and cellular composition by conventional histology and immunohistochemistry in ALTR resulting from two common total hip arthroplasty (THA) implant classes. Methods Consecutive patients presenting with ALTR from two major hip implant classes (N?=?54 patients with Dual-Modular Neck implant; N?=?14 patients with Metal-on-Metal implant) were identified from our prospective Osteolysis Tissue Database and Repository. Clinical characteristics including age, sex, BMI, length of implantation, and serum metal ion levels were recorded. Retrieved synovial tissue morphology was graded using light microscopy and cellular composition was assessed using immunohistochemistry. Results Length of implantation was shorter in the DMN group versus MoM THA group (21.3 [8.4] months versus 43.6 [13.8] months respectively; p?differences in implant performance. Morphologic examination revealed a common spectrum of neo-synovial proliferation and necrosis in both groups. Macrophages were more commonly present in diffuse sheets (Grade 3) in the MoM relative to DMN group (p?=?0.016). Perivascular lymphocytes with germinal centers (Grade 4) were more common in the DMN group, which trended towards significance (p?=?0.066). Qualitative differences in corrosion product morphology were seen between the two groups. Immunohistochemistry showed features of a CD4 and GATA-3 rich lymphocyte reaction in both implants, with increased ratios of perivascular T-cell relative to B-cell markers in the DMN relative to the MoM group (p?=?0.032). Conclusion Our results demonstrate that both implant classes display common features of neo-synovial proliferation and necrosis with a CD4 and GATA-3 rich inflammatory infiltrate. Qualitative differences in corrosion product appearance, macrophage morphology, and lymphocyte distributions were seen between the two implant types. Our data suggests that ALTR represents a histological spectrum with implant-based features. PMID:25242891



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 vision in diurnal and nocturnal hawkmoths.  


Diurnal and nocturnal hawkmoths (Sphingidae, Lepidoptera) have three spectral types of receptor sensitive to ultraviolet, blue and green light. As avid flower visitors and pollinators, they use olfactory and visual cues to find and recognise flowers. Moths of the diurnal species Macroglossum stellatarum and the nocturnal species Deilephila elpenor, Hyles lineata and Hyles gallii use and learn the colour of flowers. Nocturnal species can discriminate flowers at starlight intensities when humans and honeybees are colour-blind. M. stellatarum can use achromatic, intensity-related cues if colour cues are absent, and this is probably also true for D. elpenor. Both species can recognise colours even under a changed illumination colour. PMID:21680465

Kelber, Almut; Balkenius, Anna; Warrant, Eric J



Novel Attempts to Change the Colour of Dye Molecules Utilizing the Aggregation Mode of Saccharides  

Microsoft Academic Search

Ten saccharide-dye (azophenol and azonaphthol) conjugate molecules and four methylated reference compounds were synthesized. The purpose of the present study using these molecules is to change the colour of the common dye moiety, both in solution and in solid by the structural difference in the saccharide moieties and eventually to mimic the colour creation mechanism in a nature's flower family.

Masato Amaike; Hideki Kobayashi; Kazuo Sakurai; Seiji Shinkai



The historical frequency of head-colour morphs in the Gouldian Finch (Erythrura gouldiae)  

E-print Network

The historical frequency of head-colour morphs in the Gouldian Finch (Erythrura gouldiae) Amanda J. The endangered Gouldian Finch (Erythura gouldiae) possesses a genetic colour polymorphism in the form of three of the different Gouldian Finch morphs, we surveyed museum collections around the world, identifying 614 wild


Addition Table of Colours: Additive and Subtractive Mixtures Described Using a Single Reasoning Model  

ERIC Educational Resources Information Center

Students' misconceptions concerning colour phenomena and the apparent complexity of the underlying concepts--due to the different domains of knowledge involved--make its teaching very difficult. We have developed and tested a teaching device, the addition table of colours (ATC), that encompasses additive and subtractive mixtures in a single…

Mota, A. R.; Lopes dos Santos, J. M. B.



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



Plasmonic nanoresonators for high-resolution colour filtering and spectral imaging  

Microsoft Academic Search

Colour and spectral imaging systems typically use filters and glass prisms to disperse light of different wavelengths. With the miniaturization of integrated devices, current research on imaging sensors focuses on novel designs aiming at high efficiency, low power consumption and slim dimension, which poses great challenges to the traditional colourant-based filtering and prism-based spectral splitting techniques. In this context, surface

Ting Xu; Yi-Kuei Wu; Xiangang Luo; L. Jay Guo



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



Characterization of the genomic responses in early Senegalese sole larvae fed diets with different dietary triacylglycerol and total lipids levels.  


The aim of this work was to evaluate the genomic responses of premetamorphic sole larvae (9days post-hatching, dph) fed diets with different lipid and triacylglycerol (TAG) content. For this purpose, two diets with high (rotifers enriched with a fish oil-based emulsion; referred to as HTAG) and low (rotifers enriched with a krill oil-based emulsion; LTAG) levels of total lipids and TAG were evaluated. Lipid class and fatty acid (FA) profiles, histological characterization of intestine, liver and pancreas and expression patterns using RNA-seq were determined. Discriminant analysis results showed that larvae could be clearly differentiated on the basis of their FA profile as a function of the diet supplied until 9dph although no difference in growth was observed. RNA-seq analysis showed that larvae fed HTAG activated coordinately the transcription of apolipoproteins (apob, apoa4, apoc2, apoe, and apobec2) and other related transcripts involved in chylomicron formation, likely to facilitate proper lipid absorption and delivery. In contrast, larvae fed LTAG showed higher mRNA levels of several pancreatic enzymes (try1a, try2, cela1, cela3, cela4, chym1, chym2, amy2a and pnlip) and appetite modulators (agrp1) and some intra- and extracellular lipases. Moreover, KEGG analysis also showed that several transcripts related to lipid metabolism and glycolysis were differentially expressed with a higher abundance in larvae fed LTAG diet. All these data suggest that early larvae were able to establish compensatory mechanisms for energy homeostasis regulating key molecules for FA and TAG biosynthesis, FA uptake and intracellular management of TAG and FA to warrant optimal growth rates. PMID:25463059

Hachero-Cruzado, I; Rodríguez-Rua, A; Román-Padilla, J; Ponce, M; Fernández-Díaz, C; Manchado, M



Preoperative Predictors of Ambulation Ability at Different Time Points after Total Hip Arthroplasty in Patients with Osteoarthritis  

PubMed Central

The aims of this study were to identify the preoperative factors influencing ambulation ability at different postoperative time points after total hip arthroplasty (THA) and to examine the cutoff values of predictive preoperative factors by receiver operating characteristic (ROC) curves. Forty-eight women with unilateral THA were measured for hip extensor, hip abductor, and knee extensor muscle strength in both legs; hip pain (visual analog scale, VAS); and the Timed Up and Go (TUG) test pre- and postoperatively. Multiple regression analysis indicated that preoperative knee extensor strength (? = ?0.379, R2 = 0.409) at 3 weeks, hip abductor strength (? = ?0.572, R2 = 0.570) at 4 months, and age (? = 0.758, R2 = 0.561) at 7 months were strongly associated with postoperative ambulation, measured using the TUG test. Optimal preoperative cutoff values for ambulation ability were 0.56?Nm/kg for knee extensor strength, 0.24?Nm/kg for hip abductor strength, and 73 years of age. Our results suggest that preoperative factors predicting ambulation ability vary by postoperative time point. Preoperative knee extensor strength, hip abductor strength, and age were useful predictors of ambulation ability at the early, middle, and late time points, respectively, after THA. PMID:25180097

Kamimura, Akiko; Tsutsumi, Fumio; Sunahara, Nobuhiko



Structural differences of proteins between solution state and solid state probed by attenuated total reflection Fourier transform infrared spectroscopy.  


A Fourier transform infrared (FT-IR) spectroscopic method combined with an attenuated total reflection (ATR) sampling technique has been developed to analyze protein secondary structure in both solid and solution states. The method has been applied to analyze the protein structural differences between solution state and solid state. For alpha-helix dominant proteins, beta-sheet structures increase significantly in the solid state, with significant decrease in alpha-helical structures. For beta-sheet dominant proteins, beta-sheet structures increase only moderately in the solid state. When proteins are re-dissolved in solution, their structures are re-natured to their native structures, as suggested by the fact that their structures in solution state are similar to those determined by X-ray crystallography or other spectroscopic methods in solution state. The ATR sampling technique avoids the high pressure and chemicals that are needed for the conventional potassium bromide (KBr) disc method for solid samples in FT-IR spectroscopy. Our approach from this study demonstrated that ATR sampling is more appropriate for analysis of protein structures in the solid state. PMID:19366513

Sachdeva, Amita; Cai, Shuowei



Plasma membrane associated location of sulfonated meso-tetraphenylporphyrins of different hydrophilicity probed by total internal reflection fluorescence spectroscopy.  


Sulfonated meso-tetraphenylporphyrins of different hydrophilicity were microspectrofluorimetrically examined in endothelial cells using total internal reflection (TIR) illumination or epi-illumination. Since the penetration depth of the evanescent field during TIR illumination is limited to a few hundred nanometers, photosensitizers were almost selectively examined in close vicinity to the plasma membrane. Pronounced fluorescence signals during TIR illumination were observed for the hydrophilic compounds meso-tetraphenylporphyrin tetrasulfonate (TPPS4) and meso-tetraphenylporphyrin trisulfonate (TPPS3), whereas the more lipophilic compounds meso-tetraphenylporphyrin disulfonate (TPPS2a) and meso-tetraphenylporphyrin monosulfonate (TPPS1) could only be detected under epi-illumination. Irradiation of TPPS1 and TPPS2a in the Soret band led to an increase in fluorescence intensity and formation of a photoproduct with an emission maximum around 610 nm, which was limited to intracellular compartments. In contrast, fluorescence spectra of TPPS3 and TPPS4 obtained by TIR and epi-illumination remained almost unchanged after irradiation in the Soret band. Extralysosomal location of TPPS3 and TPPS4 in close proximity to the plasma membrane was deduced from experiments with the lysosomal markers acridine orange (AO) or lysotracker yellow (LY), which were not detectable under TIR illumination. In conclusion, these results provide for the first time direct evidence for a plasma membrane-associated fraction of the hydrophilic compounds TPPS3 and TPPS4 in living cells. PMID:10824598

Sailer, R; Strauss, W S; Emmert, H; Stock, K; Steiner, R; Schneckenburger, H



Matrix models and graph colouring  

NASA Astrophysics Data System (ADS)

We study an edge-colouring problem on random planar graphs which is one of the simplest vertex models that may be analyzed by standard methods of large N matrix models. The main features of the saddle point solution and its critical behaviour are described. At the critical value of the coupling gcr the eigen value density u(?)M is found to vanish at the border of the support as ?-a2/3.

Cicuta, Giovanni M.; Molinari, Luca; Montaldi, Emilio



Colour Image Segmentation: A Survey  

Microsoft Academic Search

Image segmentation, i.e., identi#cation of homogeneous regions in the image, hasbeen the subject of considerable research activityover the last three decades. Manyalgorithms have been elaborated for gray scale images. However, the problem ofsegmentation for colour images, which convey much more information about objectsin scenes, has received much less attention of scienti#c community. While severalsurveys of monochrome image segmentation techniques were

Wladyslaw Skarbek; Andreas Koschan



Organic and total mercury in muscle tissue of five aquatic birds with different feeding habits from the SE Gulf of California, Mexico  

Microsoft Academic Search

We measured organic and total Hg in muscle tissue of five species of aquatic birds from the south-eastern gulf of California region, Mexico. Concentrations of total and organic Hg measured in Pelecanus occidentalis were the highest (2.85 and 2.68?gg?1); lowest values of organic Hg (0.20?gg?1) and total Hg (0.47?gg?1) were detected in Anas discors and Anas clypeata, respectively. Differences of

J. Ruelas-Inzunza; J. Hernández-Osuna; F. Páez-Osuna



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. PMID:21957131

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



Carotenoid accumulation strategies for becoming a colourful House Finch: analyses of plasma and liver pigments in wild moulting birds  

Microsoft Academic Search

Summary 1. Male House Finches (Carpodacus mexicanus) colour their sexually selected plumage with carotenoid pigments, and there has been much interest in the factors that affect their ability to become bright red rather than drab yellow. 2. There is good support for the notions that health, nutritional condition and total carotenoid intake influence colour expression, but there are also suggestions




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



Fruit over sunbed: Carotenoid skin colouration is found more attractive than melanin colouration.  


Skin colouration appears to play a pivotal part in facial attractiveness. Skin yellowness contributes to an attractive appearance and is influenced both by dietary carotenoids and by melanin. While both increased carotenoid colouration and increased melanin colouration enhance apparent health in Caucasian faces by increasing skin yellowness, it remains unclear, firstly, whether both pigments contribute to attractiveness judgements, secondly, whether one pigment is clearly preferred over the other, and thirdly, whether these effects depend on the sex of the face. Here, in three studies, we examine these questions using controlled facial stimuli transformed to be either high or low in (a) carotenoid colouration, or (b) melanin colouration. We show, firstly, that both increased carotenoid colouration and increased melanin colouration are found attractive compared to lower levels of these pigments. Secondly, we show that carotenoid colouration is consistently preferred over melanin colouration when levels of colouration are matched. In addition, we find an effect of the sex of stimuli with stronger preferences for carotenoids over melanin in female compared to male faces, irrespective of the sex of the observer. These results are interpreted as reflecting preferences for sex-typical skin colouration: men have darker skin than women and high melanization in male faces may further enhance this masculine trait, thus carotenoid colouration is not less desirable, but melanin colouration is relatively more desirable in males compared to females. Taken together, our findings provide further support for a carotenoid-linked health-signalling system that is highly important in mate choice. PMID:25014019

Lefevre, Carmen E; Perrett, David I



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.



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



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



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. PMID:22590581

Matrková, Jana; Remeš, Vladimír



Impact parameter dependent colour glass condensate dipole model  

E-print Network

We show that the colour glass condensate dipole model of Iancu, Itakura and Munier, improved to include the impact parameter dependence, gives a good fit to the total gamma* p cross section measured at HERA if the anomalous dimension at the saturation scale, gamma_s, is treated as a free parameter. We find that the optimum value of gamma_s = 0.46 is close to the value determined from numerical solution of the Balitsky-Kovchegov equation. The impact parameter dependent saturation scale is generally less than 0.5 GeV^2 in the HERA kinematic regime for the most relevant impact parameters b ~ 2-3 GeV^{-1}. We compare predictions of the model to data on the longitudinal and heavy flavour structure functions, exclusive diffractive vector meson production and deeply virtual Compton scattering at HERA. The model is found to be deficient for observables sensitive to moderately small dipole sizes, where an alternative model with explicit DGLAP evolution performs better. The energy dependence of exclusive diffractive processes is shown to provide an important discriminator between different dipole model cross sections.

G. Watt; H. Kowalski




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...


Allergy, total IgE and eosinophils in East and West -- serious effects of different degrees of helminthiasis and smoking.  


Allergies are rarer in East Germany than in West Germany, although elevated IgE-levels and blood eosinophil counts can be found in the East. The aim of this study is to control the known results in Slowakia. The total-IgE and the blood eosinophil counts as well as stool samples of 311 plant-workers in Slovakia and 522 in West Germany were checked. In 1999/2000 21% of the plant workers examined in Slovakia suffered from an allergy compared with 32 % of the workers in West Germany. In contrast the total IgE in the East (Slovakia) was 166 IU/ml compared with 99 IU/ml in West Germany. Worms were detected in the stools in 7 % of those examined in the East and in only 1 % of those in the West. The percentage distribution of eosinophils in the blood was on average 7.5% in the East and 2.7% in the West. 39% of the workers in the East were smokers compared with 20% in the West. Nevertheless among non-smoking workers volunteers without parasites, the total IgE and eosinophil count were higher in those from the East than in those from the West. For Slowakia we can show for the first time that allergies are less frequent compared with West-Germany. The total IgE and the blood eosinophils are associated with higher smoking habits and more frequent helminthic diseases. PMID:11891146

Schneider, Michael; Hilgers, R H; Sennekamp, J



Robust colour calibration of an imaging system using a colour space transform and advanced regression modelling.  


A new algorithm for the conversion of device dependent RGB colour data into device independent L*a*b* colour data without introducing noticeable error has been developed. By combining a linear colour space transform and advanced multiple regression methodologies it was possible to predict L*a*b* colour data with less than 2.2 colour units of error (CIE 1976). By transforming the red, green and blue colour components into new variables that better reflect the structure of the L*a*b* colour space, a low colour calibration error was immediately achieved (?E(CAL) = 14.1). Application of a range of regression models on the data further reduced the colour calibration error substantially (multilinear regression ?E(CAL) = 5.4; response surface ?E(CAL) = 2.9; PLSR ?E(CAL) = 2.6; LASSO regression ?E(CAL) = 2.1). Only the PLSR models deteriorated substantially under cross validation. The algorithm is adaptable and can be easily recalibrated to any working computer vision system. The algorithm was tested on a typical working laboratory computer vision system and delivered only a very marginal loss of colour information ?E(CAL) = 2.35. Colour features derived on this system were able to safely discriminate between three classes of ham with 100% correct classification whereas colour features measured on a conventional colourimeter were not. PMID:22464923

Jackman, Patrick; Sun, Da-Wen; Elmasry, Gamal



Why colour in subterranean vertebrates? Exploring the evolution of colour patterns in caecilian amphibians  

Microsoft Academic Search

aposematism; caecilians; colour; crypsis; evolution; Gymnophiona; independent contrasts; pattern; selection. Abstract The proximate functions of animal skin colour are difficult to assign as they can result from natural selection, sexual selection or neutral evolution under genetic drift. Most often colour patterns are thought to signal visual stimuli; so, their presence in subterranean taxa is perplexing. We evaluate the adaptive nature




'Unnatural Colours': An introduction to colouring techniques in silent era movies  

Microsoft Academic Search

'Natural colour' was the term coined for genuine colour photography to separate it from colouring or 'painting' monochrome images, hence the use of the contrasting term 'unnatural'. The intention of this paper is to provide a guide to the technical literature on the subject. It reviews where the technologies originated, the principle literature of the time, and later, that describes

Paul Read



Reproductive isolation caused by colour pattern mimicry.  


Speciation is facilitated if ecological adaptation directly causes assortative mating, but few natural examples are known. Here we show that a shift in colour pattern mimicry was crucial in the origin of two butterfly species. The sister species Heliconius melpomene and Heliconius cydno recently diverged to mimic different model taxa, and our experiments show that their mimetic coloration is also important in choosing mates. Assortative mating between the sister species means that hybridization is rare in nature, and the few hybrids that are produced are non-mimetic, poorly adapted intermediates. Thus, the mimetic shift has caused both pre-mating and post-mating isolation. In addition, individuals from a population of H. melpomene allopatric to H. cydno court and mate with H. cydno more readily than those from a sympatric population. This suggests that assortative mating has been enhanced in sympatry. PMID:11357131

Jiggins, C D; Naisbit, R E; Coe, R L; Mallet, J



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. PMID:10103281

Quednau, M.; Ahrné, S.; Molin, G.



Organic and total mercury in muscle tissue of five aquatic birds with different feeding habits from the SE Gulf of California, Mexico.  


We measured organic and total Hg in muscle tissue of five species of aquatic birds from the south-eastern gulf of California region, Mexico. Concentrations of total and organic Hg measured in Pelecanus occidentalis were the highest (2.85 and 2.68 microgg(-1)); lowest values of organic Hg (0.20 microgg(-1)) and total Hg (0.47 microgg(-1)) were detected in Anas discors and Anas clypeata, respectively. Differences of Hg levels were related to feeding habits, being concentrations in birds of piscivorous habits more elevated than corresponding values in non-piscivorous species. PMID:19419748

Ruelas-Inzunza, J; Hernández-Osuna, J; Páez-Osuna, F



Genetics and chemistry of flower colour variation in Lathyrus odoratus  

Microsoft Academic Search

Summary  1. The inheritance of two new flower colour factors—bright and salmon—is described. Bright is an incomplete recessive, and\\u000a salmon a recessive factor hypostatic to red (e).\\u000a \\u000a 2. Two factors, red (e) and salmon (sm), are associated with a difference in the degree of oxidation of the anthocyanins in the flowers, and with a similar difference\\u000a in the leucoanthocyanins in the

G. H. Beale; G. M. Robinson; Robert Robinson; R. Scott-Moncrieff



Ultraviolet sensitivity and colour vision in raptor foraging.  


Raptors have excellent vision, yet it is unclear how they use colour information. It has been suggested that raptors use ultraviolet (UV) reflections from vole urine to find good hunting grounds. In contrast, UV plumage colours in songbirds such as blue tits are assumed to be 'hidden' communication signals, inconspicuous to raptors. This ambiguity results from a lack of knowledge about raptor ocular media transmittance, which sets the limit for UV sensitivity. We measured ocular media transmittance in common buzzards (Buteo buteo), sparrowhawks (Accipiter nisus), red kites (Milvus milvus) and kestrels (Falco tinnunculus) so that, for the first time, raptor UV sensitivity can be fully described. With this information, and new measurements of vole urine reflectance, we show that (i) vole urine is unlikely to provide a reliable visual signal to hunting raptors and (ii) blue tit plumage colours are more contrasting to blue tits than to sparrowhawks because of UV reflectance. However, as the difference between blue tit and sparrowhawk vision is subtle, we suggest that behavioural data are needed to fully resolve this issue. UV cues are of little or no importance to raptors in both vole and songbird interactions and the role of colour vision in raptor foraging remains unclear. PMID:23785106

Lind, Olle; Mitkus, Mindaugas; Olsson, Peter; Kelber, Almut



Mineralization in Rust-coloured Acarospora  

Microsoft Academic Search

The upper cortex and extracellular hyphal wall matrix are mineralized in both rust-coloured Acarospora sinopica and the paler A. smaragdula ‘f. subochracea’ in the form of microgranular or microbotryoidal phases. Analysis confirmed the distinctive colours are not simply due to hydrated iron oxides, as previously believed, and suggests mixed sulphide and oxide phases with little crystallinity, as well as other

O. William Purvis; Anton Kearsley; Gordon Cressey; Anna T. Crewe; Mats Wedin



Measurement of skin colour in vivo  

Microsoft Academic Search

Synopsis--Surface colours can be measured by a number of METHODS based on REFLECTOMETRY, COLORIMETRY and VISUAL STANDARDS. In both humans and animals, difficulties arise because the SKIN COLOUR may change owing to changes in blood flow, caused by the pressure exerted by the measuring instrument, because the skin surface is easily deformed, and because it may be impossible to take




Quaternionic wavelet transform for colour images  

Microsoft Academic Search

Quaternionic Wavelet Transform (QWT) already exist but it dealt with greyscale images. In this paper we propose a quaternionic wavelet transform aimed to colour image processing. To encode colour information in our new transformation, a pixel in the spatial domain is represented by a quaternion as described by Sangwine. First, we propose to use the discrete quaternionic Fourier transform to

Philippe Carré; Patrice Denis



The Aurora Borealis and its Colours  

Microsoft Academic Search

IN reference to Mr. Backhouse's letter last week (p. 145) we have nowhere stated that ``similarity in colour in electric discharges is sufficient to indicate similarity of constitution, eyen when their spectra are quite unlike'' If Mr. Backhouse will again read our paper on the Auroræ, he will see that we say that in the same gas the colour of

Warren de La Rue; Hugo Müller



Pigment chemistry and colour of Pelargonium flowers  

Microsoft Academic Search

The major factors responsible for colour variation in a range of Pelargonium species and cultivars were shown to be the types and relative levels of pigments present. Variations in pH and copigment levels were not found to contribute significantly. Flowers with colours ranging from cream and pink through to deep purple, including salmon, orange and red, were studied. While either

Kevin A. Mitchell; Kenneth R. Markham; Murray R. Boase



Instant colour photography: chemistry and UV stabilization  

Microsoft Academic Search

An ultraviolet (UV) screening agent precursor, dinonylphenylisophthalate, applied as a component of a surface coating on instant colour positive photographic prints stabilizes the dyes that are used and prevents the fading of colour that otherwise occurs. It is believed that upon exposure to UV light the ester precursor rearrangesin situ to form substituted benzophenones, which are effective UV screening agents.

A. M. Usmani; I. O. Salyer



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



Nectar, not colour, may lure insects to their death  

PubMed Central

We experimentally demonstrate in the field that prey of the carnivorous plant Sarracenia purpurea are attracted to sugar, not to colour. Prey capture (either all taxa summed or individual common taxa considered separately) was not associated with total red area or patterning on pitchers of living pitcher plants. We separated effects of nectar availability and coloration using painted ‘pseudopitchers’, half of which were coated with sugar solution. Unsugared pseudopitchers captured virtually no prey, whereas pseudopitchers with sugar solution captured the same amount of prey as living pitchers. In contrast to a recent study that associated red coloration with prey capture but that lacked controls for nectar availability, we infer that nectar, not colour, is the primary means by which pitcher plants attract prey. PMID:19429649

Bennett, Katherine F.; Ellison, Aaron M.



Nectar, not colour, may lure insects to their death.  


We experimentally demonstrate in the field that prey of the carnivorous plant Sarracenia purpurea are attracted to sugar, not to colour. Prey capture (either all taxa summed or individual common taxa considered separately) was not associated with total red area or patterning on pitchers of living pitcher plants. We separated effects of nectar availability and coloration using painted 'pseudopitchers', half of which were coated with sugar solution. Unsugared pseudopitchers captured virtually no prey, whereas pseudopitchers with sugar solution captured the same amount of prey as living pitchers. In contrast to a recent study that associated red coloration with prey capture but that lacked controls for nectar availability, we infer that nectar, not colour, is the primary means by which pitcher plants attract prey. PMID:19429649

Bennett, Katherine F; Ellison, Aaron M



Colour-rendition properties of solid-state lamps  

Microsoft Academic Search

The applicability of colour-quality metrics to solid-state light sources is validated and the results of the assessment of colour-rendition characteristics of various lamps are presented. The standard colour-rendering index metric or a refined colour-quality scale metric fails to distinguish between two principle colour-rendition properties of illumination: the ability to render object colours with high fidelity and the ability to increase

A. Zukauskas; R. Vaicekauskas; M. S. Shur



Adaptive colour polymorphism of Acrida ungarica H. (Orthoptera: Acrididae) in a spatially heterogeneous environment  

NASA Astrophysics Data System (ADS)

Intra-specific colour polymorphism provides a cryptic camouflage from predators in heterogeneous habitats. The orthoptera species, Acrida ungarica (Herbst, 1786) possess two well-distinguished colour morphs: brown and green and displays several disruptive colouration patterns within each morph to improve the crypsis. This study focused on how the features of the background environment relate to the proportion of the two morphs and to the intensity of disruptive colouration patterns in A. ungarica. As the two sexes are very distinct with respect to mass and length, we also distinctively tested the relationship for each sex. In accordance with the background matching hypothesis, we found that, for both sexes, the brown morph was in higher proportion at sites with a brown-dominant environment, and green morphs were in higher proportion in green-dominant environments. Globally, individuals in drier sites and in the drier year also had more intense disruptive colouration patterns, and brown morphs and females were also more striped. Colour patterns differed largely between populations and were significantly correlated with relevant environmental features. Even if A. ungarica is a polymorphic specialist, disruptive colouration still appears to provide strong benefits, particularly in some habitats. Moreover, because females are larger, they are less able to flee, which might explain the difference between sexes.

Pellissier, Loïc; Wassef, Jérôme; Bilat, Julia; Brazzola, Gregory; Buri, Pierrick; Colliard, Caroline; Fournier, Bertrand; Hausser, Jacques; Yannic, Glenn; Perrin, Nicolas



The HIrisPlex system for simultaneous prediction of hair and eye colour from DNA.  


Recently, the field of predicting phenotypes of externally visible characteristics (EVCs) from DNA genotypes with the final aim of concentrating police investigations to find persons completely unknown to investigating authorities, also referred to as Forensic DNA Phenotyping (FDP), has started to become established in forensic biology. We previously developed and forensically validated the IrisPlex system for accurate prediction of blue and brown eye colour from DNA, and recently showed that all major hair colour categories are predictable from carefully selected DNA markers. Here, we introduce the newly developed HIrisPlex system, which is capable of simultaneously predicting both hair and eye colour from DNA. HIrisPlex consists of a single multiplex assay targeting 24 eye and hair colour predictive DNA variants including all 6 IrisPlex SNPs, as well as two prediction models, a newly developed model for hair colour categories and shade, and the previously developed IrisPlex model for eye colour. The HIrisPlex assay was designed to cope with low amounts of template DNA, as well as degraded DNA, and preliminary sensitivity testing revealed full DNA profiles down to 63pg input DNA. The power of the HIrisPlex system to predict hair colour was assessed in 1551 individuals from three different parts of Europe showing different hair colour frequencies. Using a 20% subset of individuals, while 80% were used for model building, the individual-based prediction accuracies employing a prediction-guided approach were 69.5% for blond, 78.5% for brown, 80% for red and 87.5% for black hair colour on average. Results from HIrisPlex analysis on worldwide DNA samples imply that HIrisPlex hair colour prediction is reliable independent of bio-geographic ancestry (similar to previous IrisPlex findings for eye colour). We furthermore demonstrate that it is possible to infer with a prediction accuracy of >86% if a brown-eyed, black-haired individual is of non-European (excluding regions nearby Europe) versus European (including nearby regions) bio-geographic origin solely from the strength of HIrisPlex eye and hair colour probabilities, which can provide extra intelligence for future forensic applications. The HIrisPlex system introduced here, including a single multiplex test assay, an interactive tool and prediction guide, and recommendations for reporting final outcomes, represents the first tool for simultaneously establishing categorical eye and hair colour of a person from DNA. The practical forensic application of the HIrisPlex system is expected to benefit cases where other avenues of investigation, including STR profiling, provide no leads on who the unknown crime scene sample donor or the unknown missing person might be. PMID:22917817

Walsh, Susan; Liu, Fan; Wollstein, Andreas; Kovatsi, Leda; Ralf, Arwin; Kosiniak-Kamysz, Agnieszka; Branicki, Wojciech; Kayser, Manfred



Geographically Distinct Escherichia coli O157 Isolates Differ by Lineage, Shiga Toxin Genotype, and Total Shiga Toxin Production.  


While the differential association of Escherichia coli O157 genotypes with animal and human hosts has recently been well documented, little is known about their distribution between countries and how this might affect regional disease rates. Here, we used a 48-plex single nucleotide polymorphism (SNP) assay to segregate 148 E. coli O157 isolates from Australia, Argentina, and the United States into 11 SNP lineages. We also investigated the relationship between SNP lineages, Shiga toxin (Stx) gene profiles, and total Stx production. E. coli O157 isolates clearly segregated into SNP lineages that were differentially associated with each country. Of the 11 SNP lineages, seven were detected among isolates from a single country, two were detected among isolates from all three countries, and another two were detected only among U.S. and Argentinean isolates. A number of Australian (30%) and Argentinean (14%) isolates were associated with novel, previously undescribed SNP lineages that were unique to each country. Isolates within SNP lineages that were strongly associated with the carriage of stx2a produced comparatively more Stx on average than did those lacking the stx2a subtype. Furthermore, the proportion of isolates in stx2a-associated SNP lineages was significantly higher in Argentina and the United States than Australia (P < 0.05). This study provides evidence for the geographic divergence of E. coli O157 and for a prominent role of stx2a in total Stx production. These results also highlight the need for more comprehensive studies of the global distribution of E. coli O157 lineages and the impacts of regionally predominant E. coli O157 lineages on the prevalence and severity of disease. PMID:25502531

Mellor, Glen E; Fegan, Narelle; Gobius, Kari S; Smith, Helen V; Jennison, Amy V; D'Astek, Beatriz A; Rivas, Marta; Shringi, Smriti; Baker, Katherine N K; Besser, Thomas E



Structural colouration and optical effects in the wings of Papilio peranthus  

NASA Astrophysics Data System (ADS)

The butterfly Papilio peranthus displays an iridescent green colour. Through optical measurements, structural characterizations and theoretical analyses, we reveal that the colour is actually a mixing effect of green and blue which originates from the interior multilayer structures of scales imbricated in the wings. The chromatic difference between the produced green and blue colour is attributed to the modulations in the butterfly wings. Reflected light by the inclined sides of pits changes its polarization to a perpendicular direction. Besides, elongated pits lead to anisotropic polarization conversion. A wider angle spread reflection caused by the morphology of pits and the nearly 'ideal' multilayer structures in scales may be advantageous to conspecific recognition.

Liu, Feng; Wang, Guobing; Jiang, Liping; Dong, Biqin



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



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



Influence of different temporal sampling strategies on estimating total phosphorus and suspended sediment concentration and transport in small streams  

USGS Publications Warehouse

Various temporal sampling strategies are used to monitor water quality in small streams. To determine how various strategies influence the estimated water quality, frequently collected water quality data from eight small streams (14 to 110 km2) in Wisconsin were systematically subsampled to simulate typically used strategies. These subsets of data were then used to estimate mean, median, and maximum concentrations, and with continuous daily flows used to estimate annual loads (using the regression method) and volumetrically weighted mean concentrations. For each strategy, accuracy and precision in each summary statistic were evaluated by comparison with concentrations and loads of total phosphorus and suspended sediment estimated from all available data. The most effective sampling strategy depends on the statistic of interest and study duration. For mean and median concentrations, the most frequent fixed period sampling economically feasible is best. For maximum concentrations, any strategy with samples at or prior to peak flow is best. The best sampling strategy to estimate loads depends on the study duration. For one-year studies, fixed period monthly sampling supplemented with storm chasing was best, even though loads were overestimated by 25 to 50 percent. For two to three-year load studies and estimating volumetrically weighted mean concentrations, fixed period semimonthly sampling was best.

Robertson, D.M.



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



[Total abstinence or harm reduction--different strategies of alcohol treatment in research studies and international guidelines].  


Alcohol use is considered to be one of the major factors contributing to global health burden as well as social and economic harm. Only about 16% of alcohol dependent individuals enter addiction treatment programs in Poland, with only a few more in Western Europe. The aim of the paper was to present two main treatment strategies of alcohol dependence: total abstinence and harm reduction. The advantages and disadvantages of both treatment goals are presented, pointing to a possibility of treating them as complementary strategies. A need to choose a proper, personalised patient-oriented aim of a treatment program is emphasised, with an option to revise the objective during long-term therapy. The paper describes implications from investigating the problem of alcohol dependence from a population health perspective. The surprisingly high amount of individuals remitting spontaneously from alcohol dependence without treatment is also discussed, and a possible bias resulting from analysing data on alcoholic subjects coming only from addiction centres, not from general population is taken into consideration. In the second part of the paper, American as well as British alcohol treatment guidelines are presented. PMID:23045891

Jakubczyk, Andrzej; Wojnar, Marcin



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. PMID:19692390

Vereecken, Nicolas J.; Schiestl, Florian P.



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.



Strategies for Prompt Searches for GRB Afterglows: The Discovery of GRB 001011 Optical/Near-Infrared Counterpart Using Colour-Colour Selection  

NASA Technical Reports Server (NTRS)

We report the discovery of the optical and near-infrared counterpart to GRB 001011. The GRB 001011 error box determined by Beppo-SAX was simultaneously imaged in the near-infrared by the 3.58-m. New Technology Telescope and in the optical by the 1.54-m Danish Telescope - 8 hr after the gamma-ray event. We implement the colour-colour discrimination technique proposed by Rhoads (2001) and extend it using near-IR data as well. We present the results provided by an automatic colour-colour discrimination pipe-line developed to discern the different populations of objects present in the GRB 001011 error box. Our software revealed three candidates based on single-epoch images. Second-epoch observations carried out approx. 3.2 days after the burst revealed that the most likely candidate had faded thus identifying it with the counterpart to the GRB. In deep R-band images obtained 7 months after the burst a faint (R=25.38 plus or minus 0.25) elongated object, presumably the host galaxy of GRB 001011, was detected at the position of the afterglow. The GRB 001011 afterglow is the first discovered with the assistance of colour-colour diagram techniques. We discuss the advantages of using this method and its application to boxes determined by future missions.

Gorosabel, J.; Fynbo, J. U.; Hjorth, J.; Wolf, C.; Andersen, M. I.; Pedersen, H.; Christensen, L.; Jensen, B. L.; Moller, P.; Afonso, J.; Whitaker, Ann F. (Technical Monitor)



Do feather-degrading bacteria actually degrade feather colour? No significant effects of plumage microbiome modifications on feather colouration in wild great tits.  


Parasites are known to exert selective pressures on host life history traits since the energy and nutrients needed to mount an immune response are no longer available to invest in other functions. Bird feathers harbour numerous microorganisms, some of which are able to degrade feather keratin (keratinolytic microorganisms) and affect feather integrity and colouration in vitro. Although named "feather-degrading" microorganisms, experimental evidence for their effects on feathers of free-living birds is still lacking. Here, we tested whether (i) keratinolytic microorganisms can degrade feathers in vivo and thus modify the colour of feathers during the nesting period and (ii) whether feather microorganisms have a long-term effect on the investment in colouration of newly moulted feathers. We designed treatments to either favour or inhibit bacterial growth, thus experimentally modifying plumage bacterial communities, in a wild breeding population of great tits (Parus major). Our analyses revealed no significant effects of the treatments on feather colours. Moreover, we found that differences in bacterial exposure during nesting did not significantly affect the colouration of newly moulted feathers. Our results suggest that significant feather degradation obtained during in vitro studies could have led to an overestimation of the potential of keratinolytic microorganisms to shape feather colouration in free-living birds. PMID:25228345

Jacob, Staffan; Colmas, Léa; Parthuisot, Nathalie; Heeb, Philipp



Studying the influence of package shape and colour on consumer expectations of milk desserts using word association and conjoint analysis  

Microsoft Academic Search

Food packaging plays a major role in attracting consumer attention and generating sensory and hedonic expectations; which could affect their product perception and purchase decisions. In the present study word association and conjoint analysis were used to study the influence of package shape and colour on consumer expectations of milk desserts. Six images of milk dessert packages with different colour

Gastón Ares; Rosires Deliza



Colour as an Environmental Cue when Learning a Route in a Virtual Environment: Typical and Atypical Development  

ERIC Educational Resources Information Center

Typically developing (TD) 6-year-olds and 9-year-olds, and older children and adults with Williams syndrome (WS) navigated through brick-wall mazes in a virtual environment. Participants were shown a route through three mazes, each with 6 turns. In each maze the floor of each path section was a different colour such that colour acted as an…

Farran, Emily K.; Courbois, Yannick; Van Herwegen, Jo; Cruickshank, Alice G.; Blades, Mark



Effects of differences in serum total homocysteine, folate, and vitamin B 12 on cognitive impairment in stroke patients.  


BackgroundVascular cognitive impairment-no dementia (VCIND) refers to the early or mild cognitive impairment induced by cerebral vascular injury. Research shows that serum total homocysteine (tHcy) level is an independent risk factor for cerebral vascular disease and may be closely related to cognitive function.Current studies on the tHcy level in VCIND patients are limited, and the relationship of tHcy with cognitive function remains unclear. This study aims to investigate the tHcy levels in patients with VCIND and to determine their correlation with cognitive function, as well as to provide useful clues for preventing and treating VCIND.MethodsThe tHcy, folate, and vitamin B12 levels in 82 patients with VCIND were reviewed retrospectively and compared with those of 80 stroke patients without cognitive impairment and 69 healthy controls by using the Montreal Cognitive Assessment (MoCA) scale and the event-related potential P300 to evaluate cognitive function.ResultsThe tHcy levels in the VCIND group were higher than those in the other two groups, whereas the folate and Vitamin B12 levels in the VCIND group were lower than those of the other two groups. The tHcy levels in the stroke group were higher than those in the control group, and the folate and vitamin B12 levels in the stroke group were lower than those in the control group. The patients in the VCIND group with high tHcy exhibited lower MoCA scores and prolonged P300 latency than those in with normal tHcy. Correlation analysis showed that tHcy level is positively correlated with P300 latency period and negatively correlated with MoCA score.ConclusionThe tHcy levels were significantly higher and the vitamin B12 and folate levels were significantly lower in the patients with VCIND than those in the other groups. The high tHcy levels in the VCIND patients may be correlated with impaired cognitive function. PMID:25433800

Jiang, Bo; Chen, Yumei; Yao, Guoen; Yao, Cunshan; Zhao, Hongmei; Jia, Xiangdong; Zhang, Yunyan; Ge, Junling; Qiu, Enchao; Ding, Chengyun



Why colour in subterranean vertebrates? Exploring the evolution of colour patterns in caecilian amphibians.  


The proximate functions of animal skin colour are difficult to assign as they can result from natural selection, sexual selection or neutral evolution under genetic drift. Most often colour patterns are thought to signal visual stimuli; so,their presence in subterranean taxa is perplexing. We evaluate the adaptive nature of colour patterns in nearly a third of all known species of caecilians, an order of amphibians most of which live in tropical soils and leaf litter. We found that certain colour pattern elements in caecilians can be explained based on characteristics concerning above-ground movement. Our study implies that certain caecilian colour patterns have convergently evolved under selection and we hypothesize their function most likely to be a synergy of aposematism and crypsis, related to periods when individuals move overground. In a wider context, our results suggest that very little exposure to daylight is required to evolve and maintain a varied array of colour patterns in animal skin. PMID:21462404

Wollenberg, K C; Measey, C John



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


Kinetic models for colour changes in pear puree during heating at relatively high temperatures  

Microsoft Academic Search

The effect of thermal treatments on 11° Brix pear purée were studied at temperatures from 80°C to 98°C. Changes in colour measured with colorimetric parameters (reflectance spectra, colour difference, L*, a* and b* parameters), and the variation in 5-hydroxymethylfurfural (HMF) and sugars (hexoses and sucrose) content were used to evaluate non-enzymatic browning. A kinetic model based on a two-stage mechanism

A. Ibarz; J. Pagán; S. Garza



Strong effects of various incidence and observation angles on spectrometric assessment of plumage colouration in birds  

Microsoft Academic Search

The assessment of plumage colouration has become a common procedure in many ornithological studies, especially after the discovery\\u000a of differences between avian and human visual systems, namely the avian ability to perceive ultraviolet wavelengths. There\\u000a are many techniques available for plumage colour assessment. Nevertheless, unidirectional reflectance spectrometry seems actually\\u000a to be the method of choice and is used in most

S. I. C. O. Santos; L. De Neve; J. T. Lumeij; M. I. Förschler



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.



The influence of ambient illumination on colour adaptation in three fringe photoelasticity  

NASA Astrophysics Data System (ADS)

In three fringe photoelasticity, a single colour isochromatic image is used to estimate the total fringe order by comparing the colour at each point with that of a calibration table. The generation of the calibration table is critical, and certain nuances involved therein are brought out in this paper. Ideally, the same specimen material and lighting conditions must be used for both the calibration and application experiments, which are often not possible in an industrial scenario, and colour adaptation is a simple way of suitably modifying the calibration table. Till date, only experimental analyses of the colour adaptation procedures are available in the literature; in this paper, the colour adaptation procedures are investigated from an analytical viewpoint. This study has brought out that a two-point colour adaptation scheme accounts not only for tint variation between the calibration and application specimens, but also for ambient illumination. This finding has also been experimentally verified for a benchmark problem, and thereafter extended for reflection photoelastic analyses.

Neethi Simon, B.; Kasimayan, T.; Ramesh, K.



David R. Hilbert Colour, Theories of  

E-print Network

views as Democritus and Galileo. Although the metaphysics is no longer atomistic in a strict sense, many be a property of external objects as were Democritus and Galileo. Colours as perceived are commonly seen

Hilber, David


Colour vision: parallel pathways intersect in Drosophila.  


In the last one hundred years, colour vision has been demonstrated in bees and many other insects. But the underlying neural wiring remained elusive. A new study on Drosophila melanogaster combining behavioural and genetic tools yields surprising insights. PMID:24309280

Kelber, Almut; Henze, Miriam J



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



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



The inheritance of fruit colour in apple (Malus pumila Mill.)  

E-print Network

The inheritance of fruit colour in apple (Malus pumila Mill.) Allan G. WHITE Yves LESPINASSE that red fruit colour was determined by two dominant complementary genes. Blush and red colour did key words : Skin colour, hybridization. R�SUM� Hérédité de la couleur du fruit chez le pommier (Malus

Paris-Sud XI, Université de


Salience of Primary and Secondary Colours in Infancy  

ERIC Educational Resources Information Center

Primary colour terms ("black", "white", "red", "green", "yellow", and "blue") are more fundamental in colour language than secondary colour terms ("pink", "purple", "orange", "brown", and "grey"). Here, we assess whether this distinction exists in the absence of language, by investigating whether primary colours attract and sustain preverbal…

Franklin, Anna; Pitchford, Nicola; Hart, Lynsey; Davies, Ian R. L.; Clausse, Samantha; Jennings, Siobhan



Lack of uniformity in colour matching.  

PubMed Central

1. The fraction of red in a red--green mixture matched to yellow increased as the intensities of the match constituents were increased sufficiently to bleach appreciable chlorolabe and erythrolabe. 2. All changes in matching found for a given normal trichromat, (i) with increase in the intensities of the matching components, (ii) as a function of time after the onset of very intense components, (iii) with change in the pupil region through which light enters the eye, and (iv) with change in the region of the retina under test, are consistent with the assumption that matching depends upon the absorption of light in three kinds of (individually colour blind) cones, each with its own visual pigment, provided that the lambda max densities of the latter can vary in the range 0.25--1.0 (common logarithmic units) depending upon the subject. 3. Individual differences in matching among normal (as well as among both varieties of red--green anomalous) trichromats, on the other hand, suggest that the extinction spectra of the cone pigments sensitive to long and medium wave lengths may differ from one trichromat to the next. PMID:313984

Alpern, M



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. PMID:23378925

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.




Colouring Solutions of the Ice Problem  

NASA Astrophysics Data System (ADS)

The ice problem on a lattice can be expressed in terms of arrow configurations on bonds with equal numbers of arrows pointing to and away from the vertices. In some cases vertex (ice) models can be expressed as colouring problems. We use the colouring association in conjunction with an old heuristic argument of Pauling to (re)derive the exact results for the residual entropy of ice on the square and triangular lattices.

Thompson, Colin J.



Robustness study of the different immittance spectra and frequency ranges in bioimpedance spectroscopy analysis for assessment of total body composition.  


The estimation of body fluids is a useful and common practice for assessment of disease status and therapy outcomes. Electrical bioimpedance spectroscopy (EBIS) methods are noninvasive, inexpensive and efficient alternatives for determination of body fluids. One of the main source of errors in EBIS measurements in the estimation of body fluids is capacitive coupling. In this paper an analysis of capacitive coupling in EBIS measurements was performed and the robustness of the different immittance spectra against it tested. On simulations the conductance (G) spectrum presented the smallest overall error, among all immittance spectra, in the estimation of the impedance parameters used to estimate body fluids. Afterwards the frequency range of 10-500 kHz showed to be the most robust band of the G spectrum. The accuracy of body fluid estimations from the resulting parameters that utilized G spectrum and parameters provided by the measuring device were tested on EBIS clinical measurements from growth hormone replacement therapy patients against estimations performed with dilution methods. Regarding extracellular fluid, the correlation between each EBIS method and dilution was 0.93 with limits of agreement of 1.06 ± 2.95 l for the device, 1.10 ± 2.94 l for G [10-500 kHz] and 1.04 ± 2.94 l for G [5-1000 kHz]. Regarding intracellular fluid, the correlation between dilution and the device was 0.91, same as for G [10-500 kHz] and 0.92 for G [5-1000 kHz]. Limits of agreement were 0.12 ± 4.46 l for the device, 0.09 ± 4.45 for G [10-500 kHz] and 0.04 ± 4.58 for G [5-1000 kHz]. Such close results between the EBIS methods validate the proposed approach of using G spectrum for initial Cole characterization and posterior clinical estimation of body fluids status. PMID:24854791

Buendia, R; Seoane, F; Bosaeus, I; Gil-Pita, R; Johannsson, G; Ellegård, L; Lindecrantz, K



Impact of colour adjustment on flavour stability of pale lager beers with a range of distinct colouring agents  

Microsoft Academic Search

The impact of colour adjustment on the flavour stability of five pale lager beers with a range of colouring agents such as specialty malts, colouring beer and artificial caramel colourant was investigated. The research focused on determination of the endogenous anti-oxidative potential (EAP) of the beer samples using a novel Electron Spin Resonance (ESR) method. The results were correlated with

Andrés Furukawa Suárez; Thomas Kunz; Natalia Cortés Rodríguez; James MacKinlay; Paul Hughes; Frank-Jürgen Methner



Colour coding for blood collection tube closures - a call for harmonisation.  


Abstract At least one in 10 patients experience adverse events while receiving hospital care. Many of the errors are related to laboratory diagnostics. Efforts to reduce laboratory errors over recent decades have primarily focused on the measurement process while pre- and post-analytical errors including errors in sampling, reporting and decision-making have received much less attention. Proper sampling and additives to the samples are essential. Tubes and additives are identified not only in writing on the tubes but also by the colour of the tube closures. Unfortunately these colours have not been standardised, running the risk of error when tubes from one manufacturer are replaced by the tubes from another manufacturer that use different colour coding. EFLM therefore supports the worldwide harmonisation of the colour coding for blood collection tube closures and labels in order to reduce the risk of pre-analytical errors and improve the patient safety. PMID:25324449

Simundic, Ana-Maria; Cornes, Michael P; Grankvist, Kjell; Lippi, Giuseppe; Nybo, Mads; Ceriotti, Ferruccio; Theodorsson, Elvar; Panteghini, Mauro



Effect of fining on the colour and pigment composition of young red wines.  


This work aimed to evaluate the effect of four fining agents on the colour and pigment composition of red wines of Tannat. The wines were analysed 15 days after fining and immediately after separation of sediments and bottling. Colour was evaluated by spectrophotometry and polyphenols were analysed by spectrophotometry and HPLC-DAD. The colour intensity of wine was significantly decreased by bentonite and egg albumin. The most remarkable effects on wine phenolic composition were produced by bentonite and gelatin, which significantly decreased anthocyanin and tannin concentrations, respectively. Results show that each fining agent has very different impact on the wine attributes, and their effects depended as well on the composition of the clarified wine. The use of non-traditional agents of fining, as vegetable proteins, may have less impact on the colour and anthocyanin content of red wines. PMID:24679795

González-Neves, Gustavo; Favre, Guzmán; Gil, Graciela



Colour cues proved to be more informative for dogs than brightness  

PubMed Central

The results of early studies on colour vision in dogs led to the conclusion that chromatic cues are unimportant for dogs during their normal activities. Nevertheless, the canine retina possesses two cone types which provide at least the potential for colour vision. Recently, experiments controlling for the brightness information in visual stimuli demonstrated that dogs have the ability to perform chromatic discrimination. Here, we show that for eight previously untrained dogs colour proved to be more informative than brightness when choosing between visual stimuli differing both in brightness and chromaticity. Although brightness could have been used by the dogs in our experiments (unlike previous studies), it was not. Our results demonstrate that under natural photopic lighting conditions colour information may be predominant even for animals that possess only two spectral types of cone photoreceptors. PMID:23864600

Kasparson, Anna A.; Badridze, Jason; Maximov, Vadim V.



Pleiotropic effects of coat colour-associated mutations in humans, mice and other mammals.  


The characterisation of the pleiotropic effects of coat colour-associated mutations in mammals illustrates that sensory organs and nerves are particularly affected by disorders because of the shared origin of melanocytes and neurocytes in the neural crest; e.g. the eye-colour is a valuable indicator of disorders in pigment production and eye dysfunctions. Disorders related to coat colour-associated alleles also occur in the skin (melanoma), reproductive tract and immune system. Additionally, the coat colour phenotype of an individual influences its general behaviour and fitness. Mutations in the same genes often produce similar coat colours and pleiotropic effects in different species (e.g., KIT [reproductive disorders, lethality], EDNRB [megacolon] and LYST [CHS]). Whereas similar disorders and similar-looking coat colour phenotypes sometimes have a different genetic background (e.g., deafness [EDN3/EDNRB, MITF, PAX and SNAI2] and visual diseases [OCA2, RAB38, SLC24A5, SLC45A2, TRPM1 and TYR]). The human predilection for fancy phenotypes that ignore disorders and genetic defects is a major driving force for the increase of pleiotropic effects in domestic species and laboratory subjects since domestication has commenced approximately 18,000 years ago. PMID:23583561

Reissmann, Monika; Ludwig, Arne



Ultraviolet nuptial colour determines fight success in male European green lizards (Lacerta viridis)  

PubMed Central

Animal communication through colour signals is a central theme in sexual selection. Structural colours can be just as costly and honest signals as pigment-based colours. Ultraviolet (UV) is a structural colour that can be important both in intrasexual competition and mate choice. However, it is still unknown if a UV signal alone can determine the outcome of male–male fights. European green lizard (Lacerta viridis) males develop a nuptial throat coloration with a strong UV component. Among males differing only in their manipulated UV colour, females prefer males with higher UV. Here, we experimentally decreased the UV coloration of randomly chosen males from otherwise similar male pairs to test the hypothesis that a difference in UV colour alone can affect fight success during male–male competition. Our results fully supported the hypotheses: in almost 90 per cent of the contests the male with reduced UV lost the fight. Our results show that UV can be an important signal, affecting both female mate choice and determining male fight success. PMID:21715397

Bajer, Katalin; Molnár, Orsolya; Török, János; Herczeg, Gábor



Differences in the stress distribution in the distal femur between patellofemoral joint replacement and total knee replacement: a finite element study  

PubMed Central

Background Patellofemoral joint replacement is a successful treatment option for isolated patellofemoral osteoarthritis. However, results of later conversion to total knee replacement may be compromised by periprosthetic bone loss. Previous clinical studies have demonstrated a decrease in distal femoral bone mineral density after patellofemoral joint replacement. It is unclear whether this is due to periprosthetic stress shielding. The main objective of the current study was to evaluate the stress shielding effect of prosthetic replacement with 2 different patellofemoral prosthetic designs and with a total knee prosthesis. Methods We developed a finite element model of an intact patellofemoral joint, and finite element models of patellofemoral joint replacement with a Journey PFJ prosthesis, a Richards II prosthesis, and a Genesis II total knee prosthesis. For each of these 4 finite element models, the average Von Mises stress in 2 clinically relevant regions of interest were evaluated during a simulated squatting movement until 120 degrees of flexion. Results During deep knee flexion, in the anterior region of interest, the average Von Mises stress with the Journey PFJ design was comparable to the physiological knee, while reduced by almost 25% for both the Richards II design and the Genesis II total knee joint replacement design. The average Von Mises stress in the supracondylar region of interest was similar for both patellofemoral prosthetic designs and the physiological model, with slightly lower stress for the Genesis II design. Conclusions Patellofemoral joint replacement results in periprosthetic stress-shielding, although to a smaller degree than in total knee replacement. Specific patellofemoral prosthetic design properties may result in differences in femoral stress shielding. PMID:22704638



Flower colour and cytochromes P450.  


Cytochromes P450 play important roles in biosynthesis of flavonoids and their coloured class of compounds, anthocyanins, both of which are major floral pigments. The number of hydroxyl groups on the B-ring of anthocyanidins (the chromophores and precursors of anthocyanins) impact the anthocyanin colour, the more the bluer. The hydroxylation pattern is determined by two cytochromes P450, flavonoid 3'-hydroxylase (F3'H) and flavonoid 3',5'-hydroxylase (F3'5'H) and thus they play a crucial role in the determination of flower colour. F3'H and F3'5'H mostly belong to CYP75B and CYP75A, respectively, except for the F3'5'Hs in Compositae that were derived from gene duplication of CYP75B and neofunctionalization. Roses and carnations lack blue/violet flower colours owing to the deficiency of F3'5'H and therefore lack the B-ring-trihydroxylated anthocyanins based upon delphinidin. Successful redirection of the anthocyanin biosynthesis pathway to delphinidin was achieved by expressing F3'5'H coding regions resulting in carnations and roses with novel blue hues that have been commercialized. Suppression of F3'5'H and F3'H in delphinidin-producing plants reduced the number of hydroxyl groups on the anthocyanidin B-ring resulting in the production of monohydroxylated anthocyanins based on pelargonidin with a shift in flower colour to orange/red. Pelargonidin biosynthesis is enhanced by additional expression of a dihydroflavonol 4-reductase that can use the monohydroxylated dihydrokaempferol (the pelargonidin precursor). Flavone synthase II (FNSII)-catalysing flavone biosynthesis from flavanones is also a P450 (CYP93B) and contributes to flower colour, because flavones act as co-pigments to anthocyanins and can cause blueing and darkening of colour. However, transgenic plants expression of a FNSII gene yielded paler flowers owing to a reduction of anthocyanins because flavanones are precursors of anthocyanins and flavones. PMID:23297355

Tanaka, Yoshikazu; Brugliera, Filippa



Flower colour and cytochromes P450†  

PubMed Central

Cytochromes P450 play important roles in biosynthesis of flavonoids and their coloured class of compounds, anthocyanins, both of which are major floral pigments. The number of hydroxyl groups on the B-ring of anthocyanidins (the chromophores and precursors of anthocyanins) impact the anthocyanin colour, the more the bluer. The hydroxylation pattern is determined by two cytochromes P450, flavonoid 3?-hydroxylase (F3?H) and flavonoid 3?,5?-hydroxylase (F3?5?H) and thus they play a crucial role in the determination of flower colour. F3?H and F3?5?H mostly belong to CYP75B and CYP75A, respectively, except for the F3?5?Hs in Compositae that were derived from gene duplication of CYP75B and neofunctionalization. Roses and carnations lack blue/violet flower colours owing to the deficiency of F3?5?H and therefore lack the B-ring-trihydroxylated anthocyanins based upon delphinidin. Successful redirection of the anthocyanin biosynthesis pathway to delphinidin was achieved by expressing F3?5?H coding regions resulting in carnations and roses with novel blue hues that have been commercialized. Suppression of F3?5?H and F3?H in delphinidin-producing plants reduced the number of hydroxyl groups on the anthocyanidin B-ring resulting in the production of monohydroxylated anthocyanins based on pelargonidin with a shift in flower colour to orange/red. Pelargonidin biosynthesis is enhanced by additional expression of a dihydroflavonol 4-reductase that can use the monohydroxylated dihydrokaempferol (the pelargonidin precursor). Flavone synthase II (FNSII)-catalysing flavone biosynthesis from flavanones is also a P450 (CYP93B) and contributes to flower colour, because flavones act as co-pigments to anthocyanins and can cause blueing and darkening of colour. However, transgenic plants expression of a FNSII gene yielded paler flowers owing to a reduction of anthocyanins because flavanones are precursors of anthocyanins and flavones. PMID:23297355

Tanaka, Yoshikazu; Brugliera, Filippa



Colour preferences and coloured bait consumption by weka Gallirallus australis, an endemic New Zealand rail  

Microsoft Academic Search

Native birds are among the non-target species that are killed in poisoning operations directed at introduced mammalian pests in New Zealand. By identifying colours that birds find unattractive, and incorporating them into poisonous baits, some deaths may be avoided. The colour preferences of weka, Gallirallus australis, an endemic New Zealand rail, were tested over 6 days by offering individual weka

Lynette Hartley; Joseph Waas; Cheryl O'Connor; Lindsay Matthews



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


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. PMID:18445554

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



Local adaptation and divergence in colour signal conspicuousness between monomorphic and polymorphic lineages in a lizard.  


Population differences in visual environment can lead to divergence in multiple components of animal coloration including signalling traits and colour patterns important for camouflage. Divergence may reflect selection imposed by different receivers (conspecifics, predators), which depends in turn on the location of the colour patch. We tested for local adaptation of two genetically and phenotypically divergent lineages of a rock-inhabiting lizard, Ctenophorus decresii, by comparing the visual contrast of colour patches to different receivers in native and non-native environments. The lineages differ most notably in male throat coloration, which is polymorphic in the northern lineage and monomorphic in the southern lineage, but also differ in dorsal and lateral coloration, which is visible to both conspecifics and potential predators. Using models of animal colour vision, we assessed whether lineage-specific throat, dorsal and lateral coloration enhanced conspicuousness to conspecifics, increased crypsis to birds or both, respectively, when viewed against the predominant backgrounds from each lineage. Throat colours were no more conspicuous against native than non-native rock but contrasted more strongly with native lichen, which occurs patchily on rocks inhabited by C. decresii. Conversely, neck coloration (lateral) more closely matched native lichen. Furthermore, although dorsal coloration of southern males was consistently more conspicuous to birds than that of northern males, both lineages had similar absolute conspicuousness against their native backgrounds. Combined, our results are consistent with local adaptation of multiple colour traits in relation to multiple receivers, suggesting that geographic variation in background colour has influenced the evolution of lineage-specific coloration in C. decresii. PMID:25330209

McLean, C A; Moussalli, A; Stuart-Fox, D



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. PMID:20711258

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



Performance of Spodoptera litura Fabricius on different host plants: influence of nitrogen and total phenolics of plants and mid-gut esterase activity of the insect.  


Five host plants [castor, Ricinus communis (Carolus Linnaeus); cotton, Gossypium hirsutm (Carolus Linnaeus); tomato, Lycopersicum esculentum (Philip Miller); mint, Mentha arvensis (Carolus Linnaeus) and cabbage, Brassica oleracea (Carolus Linnaeus)] belonging to different families were used to study the performance of the Asian armyworm, Spodoptera litura larvae. Highest consumption of food and dry weight gain was observed in larvae fed on castor. Mint did not support optimum larval growth because of low digestibility and low efficiency of conversion of digested food to body matter. Dry weight gain ranged from 26.64 mg on mint to 86.80 mg in castor. These differences tend to be related to nitrogen and total phenolics content of the leaf tissues; however, the most clear-cut correlation is an inverse one between the host plant preference and the ratio of total phenolics to nitrogen in the leaf tissues. Mid-gut esterase activity in larvae showed an increasing trend with the increase in total phenolics: nitrogen ratio in the test plants and the order of mid-gut esterase activity in larvae was mint > cabbage > cotton > tomato > castor. PMID:15248492

Ghumare, S S; Mukherjee, S N



Experimental demonstration of singular-optical colouring of regularly scattered white light  

NASA Astrophysics Data System (ADS)

Experimental interference modelling of the effects of colouring of a beam traversing a light-scattering medium is presented. It is shown that the result of colouring of the beam at the output of the medium depends on the magnitudes of the phase delays of the singly forward scattered partial signals. The colouring mechanism has for the first time experimentally been illustrated for a forward propagating beam through a light-scattering medium. This is showed in video-fragments of the interferograms recorded within the zero interference fringe with a gradual change of the path difference of the interfering polychromatic wave trains. Spectral investigation of the effects of colouring has been carried out using a solution of liquid crystal in a polymer matrix. The amplitude ratio of the non-scattered and the singly forward scattered interfering components significantly affects the colour intensity. It has further been established that the spectral content of the illuminating beam strongly influences the colour of the resulting radiation.

Angelsky, O. V.; Hanson, S. G.; Maksimyak, P. P.; Maksimyak, A. P.; Negrych, A. L.



Dichromatic Colour Vision in Wallabies as Characterised by Three Behavioural Paradigms  

PubMed Central

Despite lacking genetic evidence of a third cone opsin in the retina of any Australian marsupial, most species tested so far appear to be trichromatic. In the light of this, we have re-examined colour vision of the tammar wallaby which had previously been identified as a dichromat. Three different psychophysical tests, based on an operant conditioning paradigm, were used to confirm that colour perception in the wallaby can be predicted and conclusively explained by the existence of only two cone types. Firstly, colour-mixing experiments revealed a Confusion Point between the three primary colours of a LCD monitor that can be predicted by the cone excitation ratio of the short- and middle-wavelength sensitive cones. Secondly, the wavelength discrimination ability in the wallaby, when tested with monochromatic stimuli, was found to be limited to a narrow range between 440 nm and 500 nm. Lastly, an experiment designed to test the wallaby’s ability to discriminate monochromatic lights from a white light provided clear evidence for a Neutral Point around 485 nm where discrimination consistently failed. Relative colour discrimination seemed clearly preferred but it was possible to train a wallaby to perform absolute colour discriminations. The results confirm the tammar wallaby as a dichromat, and so far the only behaviourally confirmed dichromat among the Australian marsupials. PMID:24489742

Ebeling, Wiebke; Hemmi, Jan M.



Exploring iris colour prediction and ancestry inference in admixed populations of South America.  


New DNA-based predictive tests for physical characteristics and inference of ancestry are highly informative tools that are being increasingly used in forensic genetic analysis. Two eye colour prediction models: a Bayesian classifier - Snipper and a multinomial logistic regression (MLR) system for the Irisplex assay, have been described for the analysis of unadmixed European populations. Since multiple SNPs in combination contribute in varying degrees to eye colour predictability in Europeans, it is likely that these predictive tests will perform in different ways amongst admixed populations that have European co-ancestry, compared to unadmixed Europeans. In this study we examined 99 individuals from two admixed South American populations comparing eye colour versus ancestry in order to reveal a direct correlation of light eye colour phenotypes with European co-ancestry in admixed individuals. Additionally, eye colour prediction following six prediction models, using varying numbers of SNPs and based on Snipper and MLR, were applied to the study populations. Furthermore, patterns of eye colour prediction have been inferred for a set of publicly available admixed and globally distributed populations from the HGDP-CEPH panel and 1000 Genomes databases with a special emphasis on admixed American populations similar to those of the study samples. PMID:25051225

Freire-Aradas, A; Ruiz, Y; Phillips, C; Maroñas, O; Söchtig, J; Tato, A Gómez; Dios, J Álvarez; de Cal, M Casares; Silbiger, V N; Luchessi, A D; Luchessi, A D; Chiurillo, M A; Carracedo, Á; Lareu, M V



Psychophysiological evidence for the genuineness of swimming-style colour synaesthesia.  


Recently, swimming-style colour synaesthesia was introduced as a new form of synaesthesia. A synaesthetic Stroop test was used to establish its genuineness. Since Stroop interference can occur for any type of overlearned association, in the present study we used a modified Stroop test and psychophysiological synaesthetic conditioning to further establish the genuineness of this form of synaesthesia. We compared the performance of a swimming-style colour synaesthete and a control who was trained on swimming-style colour associations. Our results showed that behavioural aspects of swimming-style colour synaesthesia can be mimicked in a trained control. Importantly, however, our results showed a psychophysiological conditioning effect for the synaesthete only. We discuss the theoretical relevance of swimming-style colour synaesthesia according to different models of synaesthesia. We conclude that swimming-style colour synaesthesia is a genuine form of synaesthesia, can be mimicked behaviourally in non-synaesthetes, and is best explained by a re-entrant feedback model. PMID:23247309

Rothen, Nicolas; Nikoli?, Danko; Jürgens, Uta Maria; Mroczko-W?sowicz, Aleksandra; Cock, Josephine; Meier, Beat



Coloured loops in 4D and their effective field representation  

E-print Network

Gaining insight about ensembles of magnetic configurations, that could originate the confining string tension between quarks, constitutes a major concern in current lattice investigations. This interest also applies to a different approach, where gauge models with spontaneous symmetry breaking are constructed to describe the confining string as a smooth vortex solution. In this article, we initially show how to incorporate non Abelian information into an ensemble of monopoles in $4D$, characterized by phenomenological parameters. Next, using some recent techniques developed for polymers, we were able to relate the coloured ensemble with a non Abelian gauge model. This could offer an interesting perspective to discuss some of the different approaches to describe confinement.

L. E. Oxman; G. C. Santos Rosa; B. F. I. Teixeira



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. PMID:18819948

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



Evaluation of (241)Am deposited in different parts of the leg bones and skeleton to justify in vivo measurements of the knee for estimating total skeletal activity.  


The percentage of Am deposited in different parts of leg bones relative to the total leg activity was calculated from radiochemical analysis results from six whole body donors participating in the U.S. Transuranium and Uranium Registries (USTUR). In five of these six USTUR cases, the percentage of Am deposited in the knee region as well as in the entire leg was separately calculated relative to total skeletal activity. The purpose of this study is to find a region in the leg that is both suitable for in vivo measurement of Am deposited in the bones and has a good correlation with the total skeletal Am burden. In all analyzed cases, the femur was the bone with the highest percentage of Am deposited in the leg (48.8%). In the five cases that have complete whole skeletal analysis, the percentage of Am activity in the knee relative to entire skeletal activity was 4.8%, and the average value of its coefficient of variation was 10.6%. The percentage of Am in the leg relative to total skeletal activity was 20% with an average coefficient of variation of 13.63%. The Am activity in the knee as well as in the leg was strongly correlated (R = 99.5% and R = 99.1%, respectively) with the amount of Am activity in the entire skeleton using a simple linear relationship. The highest correlation was found between the amount of Am deposited in the knee and the amount of Am deposited in the entire skeleton. This correlation is important because it might enable an accurate assessment of the total skeletal Am burden to be performed from in vivo monitoring of the knee region. In all analyzed cases, an excellent correlation (R = 99.9%) was found between the amount of Am activity in the knee and the amount of Am activity in the entire leg. The results of this study suggest three simple models: two models to predict the total skeletal activity based on either leg or knee activity, and the third model to predict the total leg activity based on knee activity. The results also suggest that the knee region is a suitable position for in vivo measurements of Am deposited in the bones and also for an accurate and efficient detection system. Detector efficiency should be apparently calibrated based on only the Am burden in the knee region bones instead of Am activity deposited in the entire leg. PMID:23192087

Khalaf, Majid; Brey, Richard R; Derryberry, DeWayne



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



Photonic-crystal full-colour displays  

NASA Astrophysics Data System (ADS)

In our information-rich world, it is becoming increasingly important to develop technologies capable of displaying dynamic and changeable data, for reasons ranging from value-added advertising to environmental sustainability. There is an intense drive at the moment towards paper-like displays, devices having a high reflectivity and contrast to provide viewability in a variety of environments, particularly in sunlight where emissive or backlit devices perform very poorly. The list of possible technologies is extensive, including electrophoretic, cholesteric liquid crystalline, electrochromic, electrodewetting, interferometric and more. Despite tremendous advances, the key drawback of all these existing display options relates to colour. As soon as an RGB (red, green and blue) colour filter or spatially modulated colour scheme is implemented, substantial light losses are inevitable even if the intrinsic reflectivity of the material is very good.

Arsenault, André C.; Puzzo, Daniel P.; Manners, Ian; Ozin, Geoffrey A.



Application of the total reflection X-ray fluorescence method to the elemental analysis of brain tumors of different types and grades of malignancy  

NASA Astrophysics Data System (ADS)

The process of carcinogenesis may influence normal biochemical reactions leading to alterations in the elemental composition of the tissue. Total reflection X-ray fluorescence analysis (TXRF) was applied to the elemental analysis of different brain tumors. The following elements were present in all the neoplastic tissues analyzed: K, Ca, Fe, Cu, Zn and Rb. The results of the analysis showed that the elemental composition of a relatively small fragment of tissue represents satisfactorily the biochemical “signature” of a cancer. On the basis of the element concentrations determined, it was possible to differentiate between some types of brain tumors.

Lankosz, M. W.; Grzelak, M.; Ostachowicz, B.; Wandzilak, A.; Szczerbowska-Boruchowska, M.; Wrobel, P.; Radwanska, E.; Adamek, D.



Effect of tea, coffee and turmeric solutions on the colour of denture base acrylic resin: an in vitro study.  


Discoloration of acrylic resin denture base when it comes in contact with various food materials and beverages in the oral cavity may cause aesthetic concern to a denture wearer. The objective of this study was to evaluate the effect of tea, coffee and turmeric solutions on the colour of different brands of heat cure acrylic resin denture base materials commonly used in India. Spectrophotometer was used to evaluate the colour change. A significant difference was found when change in colour was statistically analysed. PMID:23997464

Singh, S V; Aggarwal, Priyanki



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. PMID:24790110

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



Multi-colour detection of gravitational arcs  

NASA Astrophysics Data System (ADS)

Strong gravitational lensing provides fundamental insights into the understanding of the dark matter distribution in massive galaxies, galaxy clusters, and the background cosmology. Despite their importance, few gravitational arcs have been discovered so far. The urge for more complete, large samples and unbiased methods of selecting candidates increases. Several methods for the automatic detection of arcs have been proposed in the literature, but large amounts of spurious detections retrieved by these methods force observers to visually inspect thousands of candidates per square degree to clean the samples. This approach is largely subjective and requires a huge amount of checking by eye, especially considering the actual and upcoming wide-field surveys, which will cover thousands of square degrees. In this paper we study the statistical properties of the colours of gravitational arcs detected in the 37 deg2 of the CFHTLS-Archive-Research Survey (CARS). Most of them lie in a relatively small region of the (g' - r', r' - i') colour-colour diagram. To explain this property, we provide a model that includes the lensing optical depth expected in a ?CDM cosmology that, in combination with the sources' redshift distribution of a given survey, in our case CARS, peaks for sources at redshift z ~ 1. By furthermore modelling the colours derived from the spectral energy distribution of the galaxies that dominate the population at that redshift, the model reproduces the observed colours well. By taking advantage of the colour selection suggested by both data and model, we automatically detected 24 objects out of 90 detected by eye checking. Compared with the single-band arcfinder, this multi-band filtering returns a sample complete to 83% and a contamination reduced by a factor of ~6.5. New gravitational arc candidates are also proposed.

Maturi, Matteo; Mizera, Sebastian; Seidel, Gregor



Obtaining Online Ecological Colourings by Generalizing First-Fit  

NASA Astrophysics Data System (ADS)

A colouring of a graph is ecological if every pair of vertices that have the same set of colours in their neighbourhood are coloured alike. We consider the following problem: if a graph G and an ecological colouring c of G are given, can further vertices added to G, one at a time, be coloured using colours from some finite set C so that at each stage the current graph is ecologically coloured? If the answer is yes, then we say that the pair (G,c) is ecologically online extendible. By generalizing the well-known First-Fit algorithm, we are able to characterize when (G,c) is ecologically online extendible. For the case where c is a colouring of G in which each vertex is coloured distinctly, we give a simple characterization of when (G,c) is ecologically online extendible using only the colours of c, and we also show that (G,c) is always online extendible if we permit ourselves to use one extra colour. We also study (off-line) ecological H-colourings where the colouring must satisfy further restrictions imposed by some fixed pattern graph H. We characterize the computational complexity of this problem. This solves an open question posed by Crescenzi et al.

Johnson, Matthew; Patel, Viresh; Paulusma, Daniël; Trunck, Théophile


Classification of pre-sliced pork and Turkey ham qualities based on image colour and textural features and their relationships with consumer responses.  


Images of three qualities of pre-sliced pork and Turkey hams were evaluated for colour and textural features to characterize and classify them, and to model the ham appearance grading and preference responses of a group of consumers. A total of 26 colour features and 40 textural features were extracted for analysis. Using Mahalanobis distance and feature inter-correlation analyses, two best colour [mean of S (saturation in HSV colour space), std. deviation of b*, which indicates blue to yellow in L*a*b* colour space] and three textural features [entropy of b*, contrast of H (hue of HSV colour space), entropy of R (red of RGB colour space)] for pork, and three colour (mean of R, mean of H, std. deviation of a*, which indicates green to red in L*a*b* colour space) and two textural features [contrast of B, contrast of L* (luminance or lightness in L*a*b* colour space)] for Turkey hams were selected as features with the highest discriminant power. High classification performances were reached for both types of hams (>99.5% for pork and >90.5% for Turkey) using the best selected features or combinations of them. In spite of the poor/fair agreement among ham consumers as determined by Kappa analysis (Kappa-value<0.4) for sensory grading (surface colour, colour uniformity, bitonality, texture appearance and acceptability), a dichotomous logistic regression model using the best image features was able to explain the variability of consumers' responses for all sensorial attributes with accuracies higher than 74.1% for pork hams and 83.3% for Turkey hams. PMID:20374810

Iqbal, Abdullah; Valous, Nektarios A; Mendoza, Fernando; Sun, Da-Wen; Allen, Paul



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

PubMed Central

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, David Joachim; Kempenaers, Bart; Quillfeldt, Petra



Ripening of salami: Assessment of colour and aspect evolution using image analysis and multivariate image analysis.  


During ripening of salami, colour changes occur due to oxidation phenomena involving myoglobin. Moreover, shrinkage due to dehydration results in aspect modifications, mainly ascribable to fat aggregation. The aim of this work was the application of image analysis (IA) and multivariate image analysis (MIA) techniques to the study of colour and aspect changes occurring in salami during ripening. IA results showed that red, green, blue, and intensity parameters decreased due to the development of a global darker colour, while Heterogeneity increased due to fat aggregation. By applying MIA, different salami slice areas corresponding to fat and three different degrees of oxidised meat were identified and quantified. It was thus possible to study the trend of these different areas as a function of ripening, making objective an evaluation usually performed by subjective visual inspection. PMID:25437453

Fongaro, Lorenzo; Alamprese, Cristina; Casiraghi, Ernestina



Stamping colloidal photonic crystals: a facile way towards complex pixel colour patterns for sensing and displays.  


Patterning of colloidal photonic crystals (CPCs) has been strongly investigated in recent years for sensing and image displays. Rather than using traditional template-directed approaches, here microimprint lithography along with convective self-assembly is applied to generate complex CPC patterns that can be adjusted to show single- or dual-colour patterns or composite CPC patterns possessing two different colours. These composite CPC patterns show different wettability with water because of the surface chemistry of the polymers and silica used. This dramatically transforms the structural colours upon liquid infiltration. By mixing different ethanol concentrations with water, the infiltration efficiency can be further improved and easily read out from changes in reflection intensity and spectral peak shifts. Integrating these nano-architectures into devices can thus yield function as image displays and as sensors for solvents. PMID:25522262

Ding, Tao; Smoukov, Stoyan K; Baumberg, Jeremy J



Advances in methods for colour marking of mosquitoes  

PubMed Central

Background Different techniques are available for colour marking insects and each technique may be suitable for different insect species. Mosquitoes can be marked to determine population size, distribution and flight distance or distinguish closely related species. In this study, two methods of colour marking mosquitoes were described in detail and the impact of both methods on the survival and host-seeking behaviour of the malaria mosquito Anopheles gambiae sensu stricto was investigated. Methods Mosquitoes were marked in groups with fluorescent powder or fluorescent dye. The powder was applied by creating a cloud of powder in a paper cup and the dye was applied with an airbrush. The effect of marking on the survival of mosquitoes of different age groups was tested under controlled conditions. The effect of marking on the host seeking response of the mosquitoes was tested in an olfactometer with human and cow odour as baits. Results No effect of either of the marking methods was found on the survival of mosquitoes that were treated 1 or 3 days after emergence, however, the survival of mosquitoes treated 5 or 9 days after emergence was significantly reduced. The host-seeking response of mosquitoes to human or cow odour was tested in a dual-port olfactometer and was not found to be affected by treatment with fluorescent powder or dye. Conclusions Both methods are suitable for colour marking large groups of mosquitoes. Marking with fluorescent powder, however, is preferred because the method is simpler, visible without a UV light and no specific materials are required. PMID:23835091



Physicochemical and bioactive properties of different floral origin honeys from Romania  

Microsoft Academic Search

In this study, we investigated and compared the physico-chemical properties (moisture, colour, ash, and sugars content) as well as total phenols, total flavonoids and antioxidant activity of several honey samples (24) collected from different regions of Romania. The physico-chemical values were in the range of approved limits (conforming to EU legislation); excepting the monosaccharide values for one sample (T2). For

M?rghita? Liviu Al; Dezmirean Daniel; Adela Moise; Otilia Bobis; Laura Laslo; Stefan Bogdanov



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



ORIGINAL PAPER Seasonal ontogenetic colour plasticity in the adult striated  

E-print Network

February 2008 # Springer-Verlag 2008 Abstract Camouflage and warning colouration are two important forms provides a benefit of increased camouflage. Keywords Aposematism . Conspicuousness . Camouflage . Crypsis animals: cryptic colouration or camouflage, which decreases the risk of detection, and warning

Tullberg, Birgitta


Introduction With the exception of bioluminescence, animal colour pat-  

E-print Network

iridescent colouration of male damselflies is determined by variation in surface nanostructures (cuticular that are stunningly bright and iridescent in their appearance, yet functionally obscure. These colours are often

Macedonia, Joseph


Adaptive plasticity during the development of colour vision.  


Colour vision greatly enhances the discriminatory and cognitive capabilities of visual systems and is found in a great majority of vertebrates and many invertebrates. However, colour coding visual systems are confronted with the fact that the external stimuli are ambiguous because they are subject to constant variations of luminance and spectral composition. Furthermore, the transmittance of the ocular media, the spectral sensitivity of visual pigments and the ratio of spectral cone types are also variable. This results in a situation where there is no fixed relationship between a stimulus and a colour percept. Colour constancy has been identified as a powerful mechanism to deal with this set of problems; however, it is active only in a short-term time range. Changes covering longer periods of time require additional tuning mechanisms at the photoreceptor level or at postreceptoral stages of chromatic processing. We have used the trichromatic blue acara (Aequidens pulcher, Cichlidae) as a model system and studied retinal morphology and physiology, and visually evoked behaviour after rearing fish for 1-2 years under various conditions including near monochromatic lights (spectral deprivation) and two intensities of white light (controls). In general, long-term exposure to long wavelengths light had lesser effects than light of middle and short wavelengths. Within the cone photoreceptors, spectral deprivation did not change the absorption characteristics of the visual pigments. By contrast, the outer segment length of middle and long-wave-sensitive cones was markedly increased in the blue rearing group. Furthermore, in the same group, we observed a loss of 65% short-wave-sensitive cones after 2 years. These changes may be interpreted as manifestations of compensatory mechanisms aimed at restoring the balance between the chromatic channels. At the horizontal cell level, the connectivity between short-wave-sensitive cones and the H2 cone horizontal cells, and the spinule dynamics were both affected in the blue light group. This observation rules out the role of spinules as sites of chromatic feedback synapses. The light-evoked responses of H2 horizontal cells were also sensitive to spectral deprivation showing a shift of the neutral point towards short wavelengths in the blue rearing group. Interestingly, we also found an intensity effect because in the group reared in bright white light the neutral point was more towards longer wavelength than in the dim light group. Like the changes in the cones, the reactions of horizontal cells to spectral deprivation in the long wave domain can be characterised as compensatory. We also tested the spectral sensitivity of the various experimental groups of blue acara in visually evoked behaviour using the optomotor response paradigm. In this case, the changes in the relative spectral sensitivity were more complex and could not be explained by a simple extrapolation of the adaptive and compensatory processes in the outer retina. We conclude that the inner retina, and/or the optic tectum are also involved and react to the changes of the spectral environment. In summary, we have shown a considerable developmental plasticity in the colour vision system of the blue acara, where epigenetic adaptive processes at various levels of the visual system respond to the specific spectral composition of the surroundings and provide a powerful mechanism to ensure functional colour vision in different visual environments. We suggest that processes involving an active fine-tuning of the photoreceptors and the postreceptoral processing of chromatic information during ontogenetic development are a general feature of all colour vision systems. Such mechanisms would establish a functional balance between the various chromatic channels. This appears to be an essential condition for the cognitive systems to extract the relevant and stable information from the unstable and changing stimulus situation. PMID:15845347

Wagner, Hans-Joachim; Kröger, Ronald H H



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



Stamping colloidal photonic crystals: a facile way towards complex pixel colour patterns for sensing and displays  

NASA Astrophysics Data System (ADS)

Patterning of colloidal photonic crystals (CPCs) has been strongly investigated in recent years for sensing and image displays. Rather than using traditional template-directed approaches, here microimprint lithography along with convective self-assembly is applied to generate complex CPC patterns that can be adjusted to show single- or dual-colour patterns or composite CPC patterns possessing two different colours. These composite CPC patterns show different wettability with water because of the surface chemistry of the polymers and silica used. This dramatically transforms the structural colours upon liquid infiltration. By mixing different ethanol concentrations with water, the infiltration efficiency can be further improved and easily read out from changes in reflection intensity and spectral peak shifts. Integrating these nano-architectures into devices can thus yield function as image displays and as sensors for solvents.Patterning of colloidal photonic crystals (CPCs) has been strongly investigated in recent years for sensing and image displays. Rather than using traditional template-directed approaches, here microimprint lithography along with convective self-assembly is applied to generate complex CPC patterns that can be adjusted to show single- or dual-colour patterns or composite CPC patterns possessing two different colours. These composite CPC patterns show different wettability with water because of the surface chemistry of the polymers and silica used. This dramatically transforms the structural colours upon liquid infiltration. By mixing different ethanol concentrations with water, the infiltration efficiency can be further improved and easily read out from changes in reflection intensity and spectral peak shifts. Integrating these nano-architectures into devices can thus yield function as image displays and as sensors for solvents. Electronic supplementary information (ESI) available: SEM images of the stamps, optical image, reflection spectra, and table of peak wavelength and intensity. See DOI: 10.1039/c4nr05934d

Ding, Tao; Smoukov, Stoyan K.; Baumberg, Jeremy J.



Supersymmetric coloured/hairy black holes  

NASA Astrophysics Data System (ADS)

We discuss all possible spherically symmetric black hole type solutions to an N = 2 supergravity model with SO (3) gauging. The solutions consist of a one parameter family of black hole solutions evading the no-hair theorem and an isolated solution that is a supersymmetric analogue of a coloured black hole.

Meessen, Patrick



Computer analysis of Van Gogh's complementary colours  

Microsoft Academic Search

Traditionally, the analysis of visual arts is performed by human art experts only. The availability of advanced artificial intelligence techniques makes it possible to support art experts in their judgement of visual art. In this article currently available image-analysis techniques are applied. Our aim is (1) to determine how successful the usage of complementary colours was in the oeuvre of

Igor Berezhnoy; Eric O. Postma; H. Jaap Van Den Herik



How feather colour reflects its carotenoid content  

Microsoft Academic Search

Summary 1. Many birds sequester carotenoid pigments in colourful patches of feathers to advertise or compete for mates. Because carotenoids can be scarce in nature and serve valuable physiological functions, only the highest-quality individuals are thought to acquire or allocate more pigments for use in sexual displays. 2. A critical but rarely tested assumption of carotenoid-based signals is that the

Lauri Saks; Kevin McGraw; Peeter Horak



All the colours of the rainbow  

NASA Astrophysics Data System (ADS)

Our perception of colour has always been a source of fascination, so it's little wonder that studies of the phenomenon date back hundreds of years. What, though, can modern scientists learn from medieval literature -- and how do we go about it?

Smithson, Hannah E.; Gasper, Giles E. M.; McLeish, Tom C. B.



Time Optimal d-List Colouring of a Graph  

NASA Astrophysics Data System (ADS)

We present the first linear time algorithm for d-list colouring of a graph - i.e. a proper colouring of each vertex v by colours coming from lists L(v) of sizes at least deg(v). Previously, procedures with such complexity were only known for ?-list colouring, where for each vertex v one has |L(v)|??, the maximum of the vertex degrees. An implementation of the procedure is available.

Gravin, Nick


Detection of concealed substances in sealed opaque plastic and coloured glass containers using SORS  

NASA Astrophysics Data System (ADS)

The reliable detection of concealed substances in sealed opaque plastic and coloured glass containers, with low falsealarm rate, is a problem in numerous areas of security. For example, in aviation security, there is no reliable methodology for alarm resolution of substances with high chemical specificity unless the substances are in optically transparent containers. We present a recently developed method called Spatially Offset Raman Spectroscopy (SORS) which enables the discrimination of the Raman spectrum of the content substance from the Raman spectrum of the container material with no prior knowledge of either, thereby allowing unambiguous identification of the container contents. The method is effective with coloured plastic containers that are several millimetres thick and which are not see-through to the eye and also for coloured glass bottles. Such cases do not typically yield to conventional backscatter Raman spectroscopy (or have poor false-alarm rates) since the content signal is often overwhelmed by the signal from the container, which may in addition have a strong interfering fluorescence background. SORS measurement can be performed in a few seconds by shining a laser light onto the container and then measuring the Raman signal at the excitation point but also at one or more offset positions. Each measurement has different relative orthogonal contributions from the container and contents Raman spectra, so that, with no prior knowledge, the pure spectra of both the container and contents can be extracted - either by scaled subtraction or via multivariate statistical methods. The content spectrum can then be compared to a reference library of pure materials to give a threat evaluation with a confidence level not compromised by interfering signals originating from the container wall. In this paper, we describe the methods and their optimization, and characterize their performance in practical screening applications. The study shows that there is frequently a well-defined optimum spatial offset that maximizes the signal to noise ratio (SNR) of the resultant SORS spectrum and that this optimum can vary greatly depending on content and container material. It is also shown for the first time that, for a fixed total acquisition time available, a very high fraction of this time should be spent acquiring the offset spectrum. For common samples, the best results were obtained where the offset measurement was acquired for 20x longer than the zero offset position.

Bloomfield, Matthew; Loeffen, Paul W.; Matousek, Pavel



Analytical method for determining colour intensities based on Cherenkov radiation colour Quenching  

Microsoft Academic Search

In the present work a study was made for determining colour intensities using as luminous non-monochromatic source the Cherenkov\\u000a emission produced in the walls of a glass capillary which acts as luminous source itself inside of a coloured solution to\\u000a be evaluated. The reproducibility of this method has been compared with the spectrophotometric assay; the relative errors\\u000a of both analytical

C. González-Gómez; J. de D. López-González; M. A. Ferro-García



Analysis of organic colouring and binding components in colour layer of art works  

Microsoft Academic Search

Two methods of analysis of organic components of colour layers of art works have been tested: IR microspectroscopy of indigo, Cu-phthalocyanine, and Prussian blue, and MALDI-TOF-MS of proteinaceous binders and a protein-containing red dye. The IR spectra distortion common for smooth outer surfaces and polished cross sections of colour layer of art works is suppressed by reflectance measurement of microtome

S. Kuckova; I. Nemec; R. Hynek; J. Hradilova; T. Grygar



Evaluation of specific semi-empirical coastal colour algorithms using historic data sets  

Microsoft Academic Search

In this study, historic data from airborne campaigns more or less coincident with in situ sampling points in four different coastal areas were used to test the validity and robustness of semi-empirical coastal colour algorithms developed during a separate Dutch coastal water research program. Three different remote sensing devices were used for this exercise which could all simulate the spectral

M. R. Wernand; S. J. Shimwell; S. Boxall; H. M. van Aken



Effect of corn silage hybrids differing in starch and neutral detergent fiber digestibility on lactation performance and total-tract nutrient digestibility by dairy cows.  


Selection for hybrids with greater starch and NDF digestibility may be beneficial for dairy producers. The objective of this study was to determine the effect of feeding a TMR containing a floury-leafy corn silage hybrid (LFY) compared with a brown midrib corn silage hybrid (BMR) for intake, lactation performance, and total-tract nutrient digestibility in dairy cows. Ninety-six multiparous Holstein cows, 105±31d in milk at trial initiation, were stratified by DIM and randomly assigned to 12 pens of 8 cows each. Pens were randomly assigned to 1 of 2 treatments, BMR or LFY, in a completely randomized design; a 2-wk covariate period with cows fed a common diet followed by a 14-wk treatment period with cows fed their assigned treatment diet. Starch digestibilities, in situ, in vitro, and in vivo, were greater for LFY compared with BMR; the opposite was observed for NDF digestibility. Cows fed BMR consumed 1.7kg/d more dry matter than LFY. Although, actual-, energy-, and solids-corrected milk yields were greater for BMR than LFY, feed conversions (kg of milk or component-corrected milk per kg of DMI) did not differ. Fat-corrected milk and milk fat yield were similar, as milk fat content was greater for cows fed LFY (4.05%) than BMR (3.83%). Cows fed BMR had lower milk urea nitrogen concentration, but greater milk protein and lactose yields compared with LFY. Body weight change and condition score were unaffected by treatment. Total-tract starch digestibility was greater for cows fed the LFY corn silage; however, dry matter intake and milk and protein yields were greater for cows fed the BMR corn silage. Although total-tract starch digestibility was greater for cows fed the LFY corn silage, feed efficiency was not affected by hybrid type due to greater dry matter intake and milk and protein yields by cows fed the BMR corn silage. PMID:25465561

Ferraretto, L F; Fonseca, A C; Sniffen, C J; Formigoni, A; Shaver, R D



Simultaneous and successive colour discrimination in the honeybee ( Apis mellifera )  

Microsoft Academic Search

The colour discrimination of individual free-flying honeybees (Apis mellifera) was tested with simultaneous and successive viewing conditions for a variety of broadband reflectance stimuli. For simultaneous viewing bees used form vision to discriminate patterned target stimuli from homogeneous coloured distractor stimuli, and for successive discrimination bees were required to discriminate between homogeneously coloured stimuli. Bees were significantly better at a

Adrian G Dyer; Christa Neumeyer



Then and now: James Clerk Maxwell and colour  

Microsoft Academic Search

A survey of the researches of James Clerk Maxwell into the production and perception of colour is presented, and links to a selection of present day applications of colour science are indicated. Although false colour photography was not known in Maxwell's time, aspects of his work, suitably interpreted, have a bearing on the wide applicability of the technique. An outline

Richard C. Dougal; Clive A. Greated; Alan E. Marson



Colour image retrieval based on DCT-domain vector quantisation  

E-print Network

Colour image retrieval based on DCT-domain vector quantisation index histograms Z.-M. Lu and H. Burkhardt A new kind of feature for colour image retrieval based on DCT-domain vector quantisation (VQ for each colour component) are calculated from 12 DCT-VQ index sequences, respectively. The retrieval


Skin Blood Perfusion and Oxygenation Colour Affect Perceived Human Health  

Microsoft Academic Search

Skin blood perfusion and oxygenation depends upon cardiovascular, hormonal and circulatory health in humans and provides socio-sexual signals of underlying physiology, dominance and reproductive status in some primates. We allowed participants to manipulate colour calibrated facial photographs along empirically-measured oxygenated and deoxygenated blood colour axes both separately and simultaneously, to optimise healthy appearance. Participants increased skin blood colour, particularly oxygenated,

Ian D. Stephen; Vinet Coetzee; Miriam Law Smith; David I. Perrett



Inheritance of coat colour in the field spaniel dog  

E-print Network

Note Inheritance of coat colour in the field spaniel dog R Robinson St Stephens Nursery, Stephens known as roan. dog genetics / coat colour / field spaniel / breed Résumé - Hérédité de la couleur du for the heredity of coat colour in the dog (Little, 1957; Robinson, 1990), it has become apparent as work

Paris-Sud XI, Université de


they form juxtaposed pointillistic colour centres which, to our  

E-print Network

EX4 4QL, UK. E-mail: The nature of Drosophila melanogaster C.J. Reaume and M their wing colours and patterns. We seek to know how changes in genes and development can control colour weighting of inter-specific and intra-specific selection pressures affect wing colour intensity, hue

Sokolowski, Marla


The chemistry and analysis of annatto food colouring: a review  

Microsoft Academic Search

Annatto food colouring (E160b) has a long history of use in the food industry for the colouring of a wide range of food commodities. The principal colouring component of annatto is the oil-soluble diapo carotenoid bixin, which is the methyl ester of the dicarboxylic acid norbixin and soluble in aqueous alkali. Bixin and norbixin, therefore, exhibit not only physicochemical properties

M. Scotter



Performance Characterization of Clustering Algorithms for Colour Image Segmentation  

E-print Network

Performance Characterization of Clustering Algorithms for Colour Image Segmentation Dana Elena Ilea to extract the colour information that is used in the image segmentation process. The aim of this paper on a large suite of mosaic images. Index terms: Colour image segmentation, Fuzzy clustering, Competitive

Whelan, Paul F.


The Proportional Colouring Problem: Optimizing Buffers in Wireless Mesh Networks  

E-print Network

The Proportional Colouring Problem: Optimizing Buffers in Wireless Mesh Networks Florian Huc 1 I3S optimization: the proportional edge colouring problem. Given a graph G with positive weights associated to its edges, we want to find a proper edge colouring which assigns to each edge at least a proportion (given

Paris-Sud XI, Université de


Balanced colourings of strongly regular R. A. Bailey  

E-print Network

Balanced colourings of strongly regular graphs R. A. Bailey School of Mathematical Sciences, Queen is balanced if every pair of distinct colours occurs equally often on the ends of an edge. When the graph is the complete regular multipartite graph a balanced colouring is just a balanced incomplete-block design, or 2

Queen Mary, University of London


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. PMID:20802049

Tang, Xiao-Xin; Huang, Shuang-Quan



Influence of light colours on growth and stress response of rainbow trout (Oncorhynchus mykiss) under laboratory conditions.  


The influence of light colours on growth and stress response in rainbow trout Oncorhyncus mykiss (15.16?±?0.29?cm; 32.27?±?1.18?g) was studied. Fish were reared in 16 glass aquaria (140?×?30?×?80?cm) each with 12 fish under one of four different lighting spectra: yellow (546?nm), red (605?nm), blue (470?nm) and white (full spectrum, control). Experiments lasted 125?days. The stress response was evaluated by measuring cortisol levels. Body weight and total length of the fish reared under yellow light were greater compared with the other colour regimes while feed conversion ratio significantly lowers. Condition factor and specific growth rate, however, were not differentiated among experimental light treatments. Stressed fish showed lower cortisol levels under yellow light compared with other light exposures. The study indicates that under laboratory conditions, rainbow trout grow best under yellow light and that yellow light lowers the stress-induced cortisol response in this fish species. PMID:22017568

Heydarnejad, M Saeed; Parto, M; Pilevarian, A A



Totally implantable venous access devices: retrospective analysis of different insertion techniques and predictors of complications in 796 devices implanted in a single institution  

PubMed Central

Background The aim of this study was to assess the efficacy and safety of totally implanted vascular devices (TIVAD) using different techniques of insertion. Methods We performed a retrospective study using a prospective collected database of 796 consecutive oncological patients in which TIVADs were inserted. We focused on early and late complications following different insertion techniques (surgical cutdown, blind and ultrasound guided percutaneous) according to different techniques. Results Ultrasound guided technique was used in 646 cases, cephalic vein cutdown in 102 patients and percutaneous blind technique in 48 patients. The overall complication rate on insertion was 7.2% (57 of 796 cases). Early complications were less frequent using the ultrasound guided technique: arterial puncture (p?=?0.009), technical failure (p?=?0.009), access site change after first attempt (p?=?0.002); pneumothorax occurred in 4 cases, all using the blind percutaneus technique. Late complications occurred in 49 cases (6.1%) which required TIVAD removal in 43 cases and included: sepsis (29 cases), thrombosis (3 cases), dislocation (7 cases), skin dehiscence (3 cases), and severe pain (1 case). Conclusion Ultrasound guided technique is the safest option for TIVAD insertion, with the lowest rates of immediate complications. PMID:24886342



Determination of total mercury in chicken feed, its translocation to different tissues of chicken and their manure using cold vapour atomic absorption spectrometer.  


In this study, the contents of total mercury (Hg) present in poultry feed, tissues of broiler chicken and manure were assessed. For this purpose, chicken feeds (five brands), different tissues of broiler chicken of two age groups (1-3 and 4-6 week) and manure samples were collected from five commercial poultry farms of Hyderabad, Pakistan. The Hg concentrations in feeds, chicken tissues (leg, muscle, liver and heart) and manure samples were determined by CVAAS, prior to microwave assisted acid digestion in closed vessels. For validation, a certified reference material, DORM-2 was used. The limit of detection and quantitation were 0.117 and 0.382 microg/kg, respectively The Hg concentration in different chicken feed were found in the range of 8.57-16.5 microg/kg. The concentration of Hg in chicken tissues were found in the range of 2.54-5.54 microg/kg (liver), 1.27-3.86 microg/kg (muscles) and 2.13-3.27 microg/kg (heart). The bioaccumulation factors (BAF) for Hg in different tissues were found in the range of 0.092-0.269. The obtained data shows the high correlation coefficient between feed and manure, while low r-values were obtained between Hg levels in feed and tissues of broiler chicken of two age groups. PMID:20304027

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



Gender differences in distal femoral morphology and the role of gender specific implants in total knee replacement: a prospective clinical study.  


Gender differences in distal femoral morphology may affect femoral component fit using a standard range of prostheses. The clinical relevance of this is controversial. Standardised measurements were taken from the distal femora of 50 males and 50 females during total knee replacement (TKR). Corresponding measurements were taken from the respective gender specific and standard femoral components. No demographic differences were noted. Significant differences in both frequency and magnitude existed in the medial-lateral femoral component overhang between the sexes. In females, standard implants overhung at the anterior flange width (AFW) by >2mm in 24/50 (48%) and by >3mm in 17/50 (34%) (p<0.001). Also at the anterior medial-lateral width (MLA) 29/50 (58%) overhung by >2mm and 24/50 (48%) by >3mm (p<0.001). In males, standard implants overhung by >2mm in 1/50 (2%). In females, gender specific implants overhung by >2mm in 3/50 (6%). Females had a mean aspect ratio of 1.02 (0.82 to 1.35) and men 0.98 (0.79 to 1.19). Femoral component overhang can occur in females undergoing TKR and a gender specific implant would reduce the potential for medial-lateral overhang. Long term studies are awaited to quantify the clinical implications of overhang. PMID:21277212

Guy, S P; Farndon, M A; Sidhom, S; Al-Lami, M; Bennett, C; London, N J



Use of different spices as potential natural antioxidant additives on cooked beans (Phaseolus vulgaris). Increase of DPPH radical scavenging activity and total phenolic content.  


Herbs and spices, excellent sources of phenolic compounds, can be considered potential antioxidant additives. The use of spices must strike a balance between their potential antioxidant capabilities during preparation and the flavor acceptance, in order to avoid rejection of the food. The aimed of this study is to evaluate the influence of different spices and their concentrations on cooked common beans, focusing its potential as antioxidant additives. Onion, parsley, spring onion, laurel and coriander increased the antioxidant activity of preparation when used at 7.96 g of onion, 1.06 g parsley, 3.43 g spring onion, 0.25 g laurel (dry leaves), and 0.43 g coriander/100 g of cooked beans. Besides, these spices concentrations enhance total phenolics and alter the mixture protein digestibility minimally. For garlic samples it was not possible to establish a concentration that increases the antioxidant activity of cooked beans. PMID:25179942

Pereira, Marina Pelincer; Tavano, Olga Luisa



Effects of different enzyme treatments in extraction of total folate from infant formula, baby foods and other food products prior to microbiological assay and radioassay  

SciTech Connect

Four different enzyme treatments-conjugase alone, conjugase and alpha-amylase, conjugase and Pronase{reg sign} and a triple enzyme combination of conjugase, Pronase {reg sign} and alpha-amylase were applied in the extraction of total folate from infant formula, baby foods and various other foods by microbiological and radioassay methods. Significant increases (P < 0.05) in measurable folate were obtained using the triple enzyme system in spinach, Camembert cheese, soy-based infant formula and cereal-based, meat-based and fruit-based infant foods over the use of conjugase alone by the microbiological method. Increases were also observed in many of the same foods using Pronase{reg sign} or alpha-amylase in addition to conjugase alone. Increases obtained by microbiological assay were confirmed by radioassay in a number of foods studied.

De Souza, S.C.



Beyond colour perception: auditory-visual synaesthesia induces experiences of geometric objects in specific locations.  


Our brain constantly integrates signals across different senses. Auditory-visual synaesthesia is an unusual form of cross-modal integration in which sounds evoke involuntary visual experiences. Previous research primarily focuses on synaesthetic colour, but little is known about non-colour synaesthetic visual features. Here we studied a group of synaesthetes for whom sounds elicit consistent visual experiences of coloured 'geometric objects' located at specific spatial location. Changes in auditory pitch alter the brightness, size, and spatial height of synaesthetic experiences in a systematic manner resembling the cross-modal correspondences of non-synaesthetes, implying synaesthesia may recruit cognitive/neural mechanisms for 'normal' cross-modal processes. To objectively assess the impact of synaesthetic objects on behaviour, we devised a multi-feature cross-modal synaesthetic congruency paradigm and asked participants to perform speeded colour or shape discrimination. We found irrelevant sounds influenced performance, as quantified by congruency effects, demonstrating that synaesthetes were not able to suppress their synaesthetic experiences even when these were irrelevant for the task. Furthermore, we found some evidence for task-specific effects consistent with feature-based attention acting on the constituent features of synaesthetic objects: synaesthetic colours appeared to have a stronger impact on performance than synaesthetic shapes when synaesthetes attended to colour, and vice versa when they attended to shape. We provide the first objective evidence that visual synaesthetic experience can involve multiple features forming object-like percepts and suggest that each feature can be selected by attention despite it being internally generated. These findings suggest theories of the brain mechanisms of synaesthesia need to incorporate a broader neural network underpinning multiple visual features, perceptual knowledge, and feature integration, rather than solely focussing on colour-sensitive areas. PMID:22673231

Chiou, Rocco; Stelter, Marleen; Rich, Anina N



Preparation of multi-coloured different sized fluorescent gold clusters from blue to NIR, structural analysis of the blue emitting Au7 cluster, and cell-imaging by the NIR gold cluster.  


Blue, green, orange-red, red and NIR emitting gold quantum clusters have been prepared in aqueous media by using a bioactive peptide glutathione (reduced) at physiological pH. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) analyses show that the core structure sizes of the five different gold clusters are Au7 (blue), Au16 (green), Au19 (orange-red), Au21 (red) and Au22 (NIR). The photo-stability and pH-stability of these quantum clusters have been measured, and these are photo-stable against continuous UV irradiation for a few hours. They also exhibit moderate to good pH-stability within the pH range of 5-12.5. A computational study reveals the organisation of gold atoms in the thiolate-protected blue quantum cluster and its several structural parameters, including the mode of interaction of ligand molecules with Au atoms in the Au7 cluster. Interestingly, it has been found that NIR emitting gold quantum cluster can easily be internalized into the adenocarcinomic human alveolar basal epithelial cell line (A549 cell line). Moreover, a MTT assay indicates that our NIR emitting gold quantum cluster show very low cytotoxicy to A549 cancer cells. PMID:25529745

Roy, Subhasish; Baral, Abhishek; Bhattacharjee, Rameswar; Jana, Batakrishna; Datta, Ayan; Ghosh, Surajit; Banerjee, Arindam



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



Representation or context as a cognitive strategy in colour constancy?  


If an identification task with colour constancy as its objective is carried out under drastically changing illumination, do people rely mainly on colour information or do they rely on other sources of information? This question suggested two hypotheses for testing: (i) context hypothesis: people rely mainly on colour information (spectral reflectance or illumination chromaticity) to achieve colour constancy; (ii) representation hypothesis: people rely mainly on all other clues associated with colour to achieve colour constancy, including form information (any shape elements) and space information (spatial coordinates or spatial correlation). Experiment 1 showed that form information was readily associated with colour information to produce implicit representation. This gave the best colour-constancy performance (95.72%) and the fastest processing speed, so it probably used a top-down process. However, it was also prone to error owing to assumptions. Space information was not readily associated with colour information so colour-constancy performance was halved (48.73%) and processing time doubled. When the subject was deprived of both information sources and only given colour information, this resulted in the longest reaction times and the worst colour-constancy performance (41.38%). These results clearly support the representation hypothesis rather than the context hypothesis. When all three clues were available at the same time, the order of preference was: symbol, location, then colour. Experiment 2 showed that when form information was the main clue, colour-constancy performance was conceptually driven and processed more quickly; this supports the representation hypothesis. However, when form information was not used, colour constancy was data-driven, processed more slowly, and achieved an inferior identification rate overall; this supports the context hypothesis. PMID:18986062

Lin, Ta-Wei; Sun, Chun-Wang



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. PMID:12611925

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



Colour and Optical Properties of Materials: An Exploration of the Relationship Between Light, the Optical Properties of Materials and Colour  

Microsoft Academic Search

Colour is an important and integral part of everyday life, and an understanding and knowledge of the scientific principles behind colour, with its many applications and uses, is becoming increasingly important to a wide range of academic disciplines, from physical, medical and biological sciences through to the arts. Colour and the Optical Properties of Materials carefully introduces the science behind

Richard J. D. Tilley



Preparation of multi-coloured different sized fluorescent gold clusters from blue to NIR, structural analysis of the blue emitting Au7 cluster, and cell-imaging by the NIR gold cluster  

NASA Astrophysics Data System (ADS)

Blue, green, orange-red, red and NIR emitting gold quantum clusters have been prepared in aqueous media by using a bioactive peptide glutathione (reduced) at physiological pH. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) analyses show that the core structure sizes of the five different gold clusters are Au7 (blue), Au16 (green), Au19 (orange-red), Au21 (red) and Au22 (NIR). The photo-stability and pH-stability of these quantum clusters have been measured, and these are photo-stable against continuous UV irradiation for a few hours. They also exhibit moderate to good pH-stability within the pH range of 5-12.5. A computational study reveals the organisation of gold atoms in the thiolate-protected blue quantum cluster and its several structural parameters, including the mode of interaction of ligand molecules with Au atoms in the Au7 cluster. Interestingly, it has been found that NIR emitting gold quantum cluster can easily be internalized into the adenocarcinomic human alveolar basal epithelial cell line (A549 cell line). Moreover, a MTT assay indicates that our NIR emitting gold quantum cluster show very low cytotoxicy to A549 cancer cells.Blue, green, orange-red, red and NIR emitting gold quantum clusters have been prepared in aqueous media by using a bioactive peptide glutathione (reduced) at physiological pH. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) analyses show that the core structure sizes of the five different gold clusters are Au7 (blue), Au16 (green), Au19 (orange-red), Au21 (red) and Au22 (NIR). The photo-stability and pH-stability of these quantum clusters have been measured, and these are photo-stable against continuous UV irradiation for a few hours. They also exhibit moderate to good pH-stability within the pH range of 5-12.5. A computational study reveals the organisation of gold atoms in the thiolate-protected blue quantum cluster and its several structural parameters, including the mode of interaction of ligand molecules with Au atoms in the Au7 cluster. Interestingly, it has been found that NIR emitting gold quantum cluster can easily be internalized into the adenocarcinomic human alveolar basal epithelial cell line (A549 cell line). Moreover, a MTT assay indicates that our NIR emitting gold quantum cluster show very low cytotoxicy to A549 cancer cells. Electronic supplementary information (ESI) available: material, instrumentation, cellular uptake studies, cytotoxicity studies, synthesis of gold clusters, UV-Vis, fluorescence, plots, reaction details in tabulated form, ESI videos. See DOI: 10.1039/c4nr04338c

Roy, Subhasish; Baral, Abhishek; Bhattacharjee, Rameswar; Jana, Batakrishna; Datta, Ayan; Ghosh, Surajit; Banerjee, Arindam



A transparent look at the measurement and application of colour rendering in the use of LED light sources  

NASA Astrophysics Data System (ADS)

The technology for the measurement of colour rendering and colour quality is not new, but many parameters related to this issue are currently changing. A number of standard methods were developed and are used by different specialty areas of the lighting industry. CIE 13.3 has been the accepted standard implemented by many users and used for many years. Light-emitting Diode (LED) technology moves at a rapid pace and, as this lighting source finds wider acceptance, it appears that traditional colour-rendering measurement methods produce inconsistent results. Practical application of various types of LEDs yielded results that challenged conventional thinking regarding colour measurement of light sources. Recent studies have shown that the anatomy and physiology of the human eye is more complex than formerly accepted. Therefore, the development of updated measurement methodology also forces a fresh look at functioning and colour perception of the human eye, especially with regard to LEDs. This paper includes a short description of the history and need for the measurement of colour rendering. Some of the traditional measurement methods are presented and inadequacies are discussed. The latest discoveries regarding the functioning of the human eye and the perception of colour, especially when LEDs are used as light sources, are discussed. The unique properties of LEDs when used in practical applications such as luminaires are highlighted.

Leuschner, F. W.; Van Der Westhuyzen, J. G. J.



Intrasexual competition among females and the stabilization of a conspicuous colour polymorphism in a Lake Victoria cichlid fish  

PubMed Central

The maintenance of colour polymorphisms within populations has been a long-standing interest in evolutionary ecology. African cichlid fish contain some of the most striking known cases of this phenomenon. Intrasexual selection can be negative frequency dependent when males bias aggression towards phenotypically similar rivals, stabilizing male colour polymorphisms. We propose that where females are territorial and competitive, aggression biases in females may also promote coexistence of female morphs. We studied a polymorphic population of the cichlid fish Neochromis omnicaeruleus from Lake Victoria, in which three distinct female colour morphs coexist: one plain brown and two blotched morphs. Using simulated intruder choice tests in the laboratory, we show that wild-caught females of each morph bias aggression towards females of their own morph, suggesting that females of all three morphs may have an advantage when their morph is locally the least abundant. This mechanism may contribute to the establishment and stabilization of colour polymorphisms. Next, by crossing the morphs, we generated sisters belonging to different colour morphs. We find no sign of aggression bias in these sisters, making pleiotropy unlikely to explain the association between colour and aggression bias in wild fish, which is maintained in the face of gene flow. We conclude that female–female aggression may be one important force for stabilizing colour polymorphism in cichlid fish. PMID:18077255

Dijkstra, Peter D; Seehausen, Ole; Groothuis, Ton G.G



Total protein  


The total protein test measures the total amount of two classes of proteins found in the fluid portion of your blood. These are albumin and globulin. Proteins are important parts of all cells and tissues. ...


Standardized Total Average Toxicity Score: A Scale- and Grade-Independent Measure of Late Radiotherapy Toxicity to Facilitate Pooling of Data From Different Studies  

SciTech Connect

Purpose: The search for clinical and biologic biomarkers associated with late radiotherapy toxicity is hindered by the use of multiple and different endpoints from a variety of scoring systems, hampering comparisons across studies and pooling of data. We propose a novel metric, the Standardized Total Average Toxicity (STAT) score, to try to overcome these difficulties. Methods and Materials: STAT scores were derived for 1010 patients from the Cambridge breast intensity-modulated radiotherapy trial and 493 women from University Hospitals of Leicester. The sensitivity of the STAT score to detect differences between patient groups, stratified by factors known to influence late toxicity, was compared with that of individual endpoints. Analysis of residuals was used to quantify the effect of these covariates. Results: In the Cambridge cohort, STAT scores detected differences (p < 0.00005) between patients attributable to breast volume, surgical specimen weight, dosimetry, acute toxicity, radiation boost to tumor bed, postoperative infection, and smoking (p < 0.0002), with no loss of sensitivity over individual toxicity endpoints. Diabetes (p = 0.017), poor postoperative surgical cosmesis (p = 0.0036), use of chemotherapy (p = 0.0054), and increasing age (p = 0.041) were also associated with increased STAT score. When the Cambridge and Leicester datasets were combined, STAT was associated with smoking status (p < 0.00005), diabetes (p = 0.041), chemotherapy (p = 0.0008), and radiotherapy boost (p = 0.0001). STAT was independent of the toxicity scale used and was able to deal with missing data. There were correlations between residuals of the STAT score obtained using different toxicity scales (r > 0.86, p < 0.00005 for both datasets). Conclusions: The STAT score may be used to facilitate the analysis of overall late radiation toxicity, from multiple trials or centers, in studies of possible genetic and nongenetic determinants of radiotherapy toxicity.

Barnett, Gillian C., E-mail: [University of Cambridge Department of Oncology, Oncology Centre, Cambridge (United Kingdom); Cancer Research-UK Centre for Genetic Epidemiology and Department of Oncology, Strangeways Research Laboratories, Cambridge (United Kingdom); West, Catharine M.L. [School of Cancer and Enabling Sciences, Manchester Academic Health Science Centre, University of Manchester, Christie Hospital, Manchester (United Kingdom); Coles, Charlotte E. [University of Cambridge Department of Oncology, Oncology Centre, Cambridge (United Kingdom); Pharoah, Paul D.P. [Cancer Research-UK Centre for Genetic Epidemiology and Department of Oncology, Strangeways Research Laboratories, Cambridge (United Kingdom); Talbot, Christopher J. [Department of Genetics, University of Leicester, Leicester (United Kingdom); Elliott, Rebecca M. [School of Cancer and Enabling Sciences, Manchester Academic Health Science Centre, University of Manchester, Christie Hospital, Manchester (United Kingdom); Tanteles, George A. [Department of Clinical Genetics, University Hospitals of Leicester, Leicester (United Kingdom); Symonds, R. Paul [Department of Cancer Studies and Molecular Medicine, University Hospitals of Leicester, Leicester (United Kingdom); Wilkinson, Jennifer S. [University of Cambridge Department of Oncology, Oncology Centre, Cambridge (United Kingdom); Dunning, Alison M. [Cancer Research-UK Centre for Genetic Epidemiology and Department of Oncology, Strangeways Research Laboratories, Cambridge (United Kingdom); Burnet, Neil G. [University of Cambridge Department of Oncology, Oncology Centre, Cambridge (United Kingdom); Bentzen, Soren M. [University of Wisconsin, School of Medicine and Public Health, Department of Human Oncology, Madison, WI (United States)



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. PMID:18990672

Théry, Marc; Casas, Jérôme



Kinetics of colour change of raspberry, sweet ( Prunus avium) and sour ( Prunus cerasus) cherries preserves packed in glass containers: light and room temperature effects  

Microsoft Academic Search

This work studied the kinetics of colour change in preserves of raspberries, sweet and sour cherries exposed to different lighting conditions (light and darkness), at constant temperature, as well as stored at several temperatures. In all the preserves and treatments, the colour diminished noticeably during the first 90 days of storage to remain constant from then on. The kinetics of

Mónica R Ochoa; Alicia G Kesseler; Antonio De Michelis; Alicia Mugridge; Alicia R Chaves



The Anatomy and Chemistry of the Colour Bands of Grasstree Stems (Xanthorrhoea preissii) used for Plant Age and Fire History Determination  

Microsoft Academic Search

A new method of ageing and determining the fire history of grasstrees, based on colour bands running along the stem, has been developed. As part of our evaluation of the technique, we examined the structural and chemical basis of the colour differences. Exposed ends of the leaf bases are cream, brown and black, with the inner cor- tex, especially in




Attenuated total reflectance (ATR) GeO2 hollow infrared waveguides deposited from aqueous germanate ion solutions with different GeO2 concentrations  

NASA Astrophysics Data System (ADS)

The attenuated total reflectance (ATR) hollow waveguides capable of transmitting CO2 laser have attracted wide research interest due to its advantages of simple structure, no end reflection, small beam divergence and good transmission modes. In this work, GeO2 ATR hollow waveguides for delivery of CO2 laser radiations were fabricated via an acid-induced liquid phase deposition (LPD) process. GeO2 hollow waveguide samples were deposited from acidic aqueous germanate ion solutions with different GeO2 concentrations. The morphology, compactness and surface roughness of the LPD-derived GeO2 ceramic film were examined by SEM. The crystalline structure of the film sample was determined using XRD. The low-loss window of the GeO2 waveguide tube was observed by a FTIR spectrometer. We measured the transmission loss of the sample for delivery of a 10.6 ?m TEM00 CO2 laser beam. The results show that the variations in loss are consistent with the quality change of the GeO2 ceramic films grown in solutions at different concentrations.

Li, Yi; Jing, Chengbin; Chu, Junhao



Quantitative assessment of tissue sections by Reverse Colour Coding.  


Stains and dyes are frequently used to emphasise tissue structures for viewing under microscopy but few simple objective quantification methods exist. We describe the derivation of a mathematical formula enabling calculation of the relative contribution of three different coloured components to an image, which can be applied to rapid batch assessment of tissue sections for quantification of area proportions of differently stained elements. In order to validate this method, termed Reverse Colour Coding (RCC), we compared RCC estimations with known area proportions in artificially created images to calculate absolute accuracy, and compared RCC with panel visual estimation (VE) for the assessment of actual NCAM-stained muscle slides. Our results indicate that RCC has an absolute accuracy of 98-98.5% and superior inter-observer agreement and both inter- and intra-observer variability compared with VE. Results also suggest that cognitive bias occurring with VE may be eliminated by use of RCC. We submit RCC as a more accurate and less labour-intensive method of quantifying area proportions of stained tissues on microscopic images. PMID:18006070

Urso-Baiarda, Fulvio; MacQuillan, Anthony; Grobbelaar, Adriaan O



Comparison of total haemoglobin mass measured with the optimized carbon monoxide rebreathing method across different Radiometer™ ABL-80 and OSM-3 hemoximeters.  


A new Radiometer™ hemoximeter (ABL-80) has recently become available to measure carboxyhaemoglobin concentration for the optimized CO-rebreathing method (oCOR-method). Within the English Institute of Sport (EIS), hemoximeters are used in three different laboratories; therefore, precision and agreement of total haemoglobin mass (tHbmass) determination across sites is essential, and comparison to the previous model OSM-3 is desirable. Six male and one female (age 30 ± 6 years, body mass 78.1 ± 10.6 kg) undertook the oCOR-method. Venous blood (~2 ml) was sampled immediately before and at 7 min during the oCOR-method; with seven replicates from each time point simultaneously analysed on five different Radiometer™ hemoximeters [OSM-3(1), OSM-3(2), ABL-80(1), ABL-80(2) and ABL-80(3)]. There were no differences (p > 0.05) between ?%HbCO or mean tHbmass analysed with five different hemoximeters (OSM-3(1): 886 ± 167 g; OSM-3(2): 896 ± 160 g: ABL-80(1): 904 ± 157 g; ABL-80(2): 906 ± 163 g: ABL-80(3): 906 ± 162 g). However, the Bland-Altman plot revealed that there was closer agreement between ABL-80 machines for tHbmass than for the OSM-3. The variance (i.e. % error) across replicate samples decreased as the number of samples increased, with the error derived from the 'worse-case' scenario (single samples) being 1.2 to 1.6 fold greater in the OSM-3 than the ABL-80. Although there were no differences in the average tHbmass measured with five different hemoximeters, the new ABL-80 were in better agreement with each other compared to the old OSM-3. Previously, five replicates were required to achieve a low error using the OSM-3; however, three replicates are sufficient with the ABL-80 model to produce an error of ? 1% in tHbmass. PMID:25420054

Turner, G; Richardson, A J; Maxwell, N S; Pringle, J S M



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



Dissecting the mechanism of Solanum lycopersicum and Solanum chilense flower colour formation.  


Flowers are the defining feature of angiosperms, and function as indispensable organs for sexual reproduction. Flower colour typically plays an important role in attracting pollinators, and can show considerable variation, even between closely related species. For example, domesticated tomato (S. lycopersicum) has orange/yellow flowers, while the wild relative S. chilense (accession LA2405) has bright yellow flowers. In this study, the mechanism of flower colour formation in these two species was compared by evaluating the accumulation of carotenoids, assessing the expression genes related to carotenoid biosynthetic pathways and observing chromoplast ultrastructure. In S. chilense petals, genes associated with the lutein branch of the carotenoid biosynthetic pathway, phytoene desaturase (PDS), ?-carotene desaturase (ZDS), lycopene ?-cyclase (LCY-B), ?-ring hydroxylase (CRTR-B) and ?-ring hydroxylase (CRTR-E), were highly expressed, and this was correlated with high levels of lutein accumulation. In contrast, PDS, ZDS and CYC-B from the neoxanthin biosynthetic branch were highly expressed in S. lycopersicum anthers, leading to increased ?-carotene accumulation and hence an orange/yellow colour. Changes in the size, amount and electron density of plastoglobules in chromoplasts provided further evidence of carotenoid accumulation and flower colour formation. Taken together, these results reveal the biochemical basis of differences in carotenoid pigment accumulation and colour between petals and anthers in tomato. PMID:24750468

Gao, M; Qu, H; Gao, L; Chen, L; Sebastian, R S J; Zhao, L



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. PMID:23222447

Hancox, Daniel; Wilson, Robbie S.; White, Craig R.



Two-dimensional Fourier analysis of the spongy medullary keratin of structurally coloured feather barbs  

PubMed Central

We conducted two-dimensional (2D) discrete Fourier analyses of the spatial variation in refractive index of the spongy medullary keratin from four different colours of structurally coloured feather barbs from three species of bird: the rose-faced lovebird, Agapornis roseicollis (Psittacidae), the budgerigar, Melopsittacus undulatus (Psittacidae), and the Gouldian finch, Poephila guttata (Estrildidae). These results indicate that the spongy medullary keratin is a nanostructured tissue that functions as an array of coherent scatterers. The nanostructure of the medullary keratin is nearly uniform in all directions. The largest Fourier components of spatial variation in refractive index in the tissue are of the appropriate size to produce the observed colours by constructive interference alone. The peaks of the predicted reflectance spectra calculated from the 2D Fourier power spectra are congruent with the reflectance spectra measured by using microspectrophotometry. The alternative physical models for the production of these colours, the Rayleigh and Mie theories, hypothesize that medullary keratin is an incoherent array and that scattered waves are independent in phase. This assumption is falsified by the ring-like Fourier power spectra of these feathers, and the spacing of the scattering air vacuoles in the medullary keratin. Structural colours of avian feather barbs are produced by constructive interference of coherently scattered light waves from the optically heterogeneous matrix of keratin and air in the spongy medullary layer.

Prum, R. O.; Torres, R.; Williamson, S.; Dyck, J.



Diurnal lighting patterns and habitat alter opsin expression and colour preferences in a killifish  

PubMed Central

Spatial variation in lighting environments frequently leads to population variation in colour patterns, colour preferences and visual systems. Yet lighting conditions also vary diurnally, and many aspects of visual systems and behaviour vary over this time scale. Here, we use the bluefin killifish (Lucania goodei) to compare how diurnal variation and habitat variation (clear versus tannin-stained water) affect opsin expression and the preference to peck at different-coloured objects. Opsin expression was generally lowest at midnight and dawn, and highest at midday and dusk, and this diurnal variation was many times greater than variation between habitats. Pecking preference was affected by both diurnal and habitat variation but did not correlate with opsin expression. Rather, pecking preference matched lighting conditions, with higher preferences for blue at noon and for red at dawn/dusk, when these wavelengths are comparatively scarce. Similarly, blue pecking preference was higher in tannin-stained water where blue wavelengths are reduced. In conclusion, L. goodei exhibits strong diurnal cycles of opsin expression, but these are not tightly correlated with light intensity or colour. Temporally variable pecking preferences probably result from lighting environment rather than from opsin production. These results may have implications for the colour pattern diversity observed in these fish. PMID:23698009

Johnson, Ashley M.; Stanis, Shannon; Fuller, Rebecca C.



Male courtship preferences demonstrate discrimination against allopatric colour morphs in a cichlid fish  

PubMed Central

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



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



Spatially resolved colours and stellar population properties in early-type galaxies at z ˜ 1.5  

NASA Astrophysics Data System (ADS)

We present F850LP - F160W colour gradients for 11 early-type galaxies (ETGs) at 1.0 < zspec < 1.9 selected from the GOODS-South field. Significant negative F850LP - F160W colour gradients (core redder than the outskirts) have been detected in ˜70 per cent of our sample within the effective radius Re, the remaining 30 per cent having a flat colour profile consistent with a null gradient. Extending the analysis to R > Re, enclosing the whole galaxy, we have found that the fraction of high-z ETGs with negative F850LP - F160W colour gradients rises up to 100 per cent. For each galaxy, we investigate the origin of the radial colour variation with an innovative technique based on the matching of both the spatially resolved colour and the global spectral energy distribution (SED) to predictions of composite stellar population models. In fact, we find that the age of the stellar populations is the only parameter whose radial variation alone can fully account for the observed colour gradients and global SEDs for six ETGs in our sample, without the need of radial variation of any other stellar population property. For four out of these six ETGs, a pure metallicity variation can also reproduce the detected colour gradients. None the less, a minor contribution to the observed colour gradients from the radial variation of star formation time-scale, abundance of low- to high-mass stars and dust cannot be completely ruled out. For the rest of the sample, our analysis suggests a more complex scenario whereby more properties of the stellar populations need to simultaneously vary, likely with comparable weights, to generate the observed colour gradients and global SEDs. Our results show that, despite the young mean age of our galaxies (<3-4 Gyr), they already exhibit significant differences among their stellar content. We have discussed our results within the framework of the widest accepted scenarios of galaxy formation and conclude that none of them can satisfactorily account for the observed distribution of colour gradients and for the spatially resolved content of high-z ETGs. Our results suggest that the distribution of colour gradients may be due to different initial conditions in the formation mechanisms of ETGs.

Gargiulo, A.; Saracco, P.; Longhetti, M.; La Barbera, F.; Tamburri, S.



Effect of Different Light Intensities on Total Phenolics and Flavonoids Synthesis and Anti-oxidant Activities in Young Ginger Varieties (Zingiber officinale Roscoe)  

PubMed Central

Nowadays, phytochemicals and antioxidants in plants are raising interest in consumers for their roles in the maintenance of human health. Phenolics and flavonoids are known for their health-promoting properties due to protective effects against cardiovascular disease, cancers and other disease. Ginger (Zingiber officinale) is one of the traditional folk medicinal plants and it is widely used in cooking in Malaysia. In this study, four levels of glasshouse light intensities (310, 460, 630 and 790 ?mol m?2s?1) were used in order to consider the effect of light intensity on the production, accumulation and partitioning of total phenolics (TP), total flavonoids (TF) and antioxidant activities in two varieties of Malaysian young ginger (Zingiber officinale). TF biosynthesis was highest in the Halia Bara variety under 310 ?mol m?2s?1 and TP was high in this variety under a light intensity of 790 ?mol m?2s?1. The highest amount of these components accumulated in the leaves and after that in the rhizomes. Also, antioxidant activities determined by the 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) assay in both of varieties, increased significantly (p ? 0.01) with increasing TF concentration, and high antioxidant activity was observed in the leaves of Halia Bara grown under 310 ?mol m?2s?1. The ferric reducing (FRAP) activity of the rhizomes was higher than that of the leaves in 310 ?mol m?2s?1 of sun light. This study indicates the ability of different light intensities to enhance the medicinal components and antioxidant activities of the leaves and young rhizomes of Zingiber officinale varieties. Additionally, this study also validated their medicinal potential based on TF and TP contents. PMID:21152306

Ghasemzadeh, Ali; Jaafar, Hawa Z. E.; Rahmat, Asmah; Wahab, Puteri Edaroyati Megat; Halim, Mohd Ridzwan Abd



Extremal problems for colourings of uniform hypergraphs  

NASA Astrophysics Data System (ADS)

We study a classical problem (first posed by Erd?s) in the extremal theory of hypergraphs. According to Erd?s, a hypergraph possesses property B if its set of vertices admits a 2-colouring such that no edge of the hypergraph is monochromatic. The problem is to find the minimum m(n) of all m such that there is an n-uniform (each edge contains exactly n vertices) hypergraph with exactly m edges that does not possess property B. We consider more general problems (including the case of polychromatic colourings) and introduce a number of parametric properties of hypergraphs. We obtain estimates for analogues of m(n) for extremal problems on various classes of hypergraphs.

Shabanov, D. A.



A mutation in the MATP gene causes the cream coat colour in the horse  

PubMed Central

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



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.



Theory and practice of colour vision testing: A review. Part 2  

PubMed Central

Lakowski, R. (1969).Brit. J. industr. Med.,26, 265-288. Theory and practice of colour vision testing: A review. Part 2. The more modern tests of colour confusion, hue discrimination, metamerism, and special aptitudes measure a wide variety of attributes. Norms, including variations among normal as well as among defective observers, are given for each test, along with any other information we require to understand them. Finally there is the problem of choice, and factors influencing it, of which tests should be used in different circumstances. Some advice is given on the most useful combinations of tests. PMID:4899666

Lakowski, R.



Colour and light variations of PLEIONE between the Be and shell phases.  

NASA Astrophysics Data System (ADS)

Pleione (28 Tau, HD 23862) has been measured in the Geneva photometric system since 1962, particularly throughout the latest shell episode (1973-1982). Here, we present and discuss the data of the 152 measurements obtained until 1993 in the special context of the properties of the Geneva system. The photometry allows us to evaluate a reliable colour excess and quantifies the very different behaviours of the Balmer and Paschen continua during the shell phase. Apart from its long term variability, both the magnitudes and colours of Pleione show significant variability on a night-to-night timescale during that phase.

Cramer, N.; Doazan, V.; Nicolet, B.; de La Fuente, A.; Barylak, M.



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



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



Differences in Coloured Obsidians From Sierra de Pachuca, Mexico  

Microsoft Academic Search

The structural and chemical features of two obsidians from the pre-Hispanic quarry in the town of Nopalillo, Sierra de Pachuca, Hidalgo, Mexico are presented here. The obsidians were collected at a single site. The most common sample is green, glassy and transparent and the other is green-greyish and opaque. Both samples were found to have similar elemental composition.In order to

D. Tenorio; A. Cabral; P. Bosch; M. Jiménez-Reyes; S. Bulbulian



Do distinct water chemistry reservoir age and disturbance make any difference on phosphatase activity?  

Microsoft Academic Search

ABSTRACT Alkaline phosphatase activity was assessed concomitantly with total phosphorus, orthophosphate and phosphomonoester con- centrations in two ,meso-eutrophic reservoirs ,with distinct age and subjected to different kinds of environmental, influence. Differ- ences in conductivity,temperature and pH were found. However, during the study period alkaline phosphatase activity was similar in both reservoirs. Water colour was higher in S. Serrada Reservoir. This

Ana Maria Geraldes; Maria-josé Boavida


The colour of galaxies in distant groups  

NASA Astrophysics Data System (ADS)

We present new optical and near-infrared imaging for a sample of 98 spectroscopically selected galaxy groups at 0.25 < z < 0.55, most of which have velocity dispersions ? < 500kms-1. We use point spread function matched aperture photometry to measure accurate colours for group members and the surrounding field population. The sample is statistically complete above a stellar mass limit of approximately M = 1 × 1010Msolar. The overall colour distribution is bimodal in both the field and group samples; but, at fixed luminosity the fraction of group galaxies populating the red peak is larger, by ~20 +/- 7 per cent, than that of the field. In particular, group members with early-type morphologies, as identified in Hubble Space Telescope imaging, exhibit a tight red sequence, similar to that seen for more massive clusters. Using optical and near-infrared colours, including data from the Spitzer Space Telescope, we show that approximately 20-30 per cent of galaxies on the red sequence may be dust-reddened galaxies with non-negligible star formation and early-spiral morphologies. This is true of both the field and group samples, and shows little dependence on near-infrared luminosity. Thus, the fraction of bright (0.4MK < -22) group members with no sign of star formation or active galactic nuclei activity, as identified by their colours or [OII] emission, is 54 +/- 6 per cent. Our field sample, which includes galaxies in all environments, contains 35 +/- 3 per cent of such inactive galaxies, consistent with the amount expected if all such galaxies are located in groups and clusters. This reinforces our earlier conclusions that dense environments at z <~ 0.5 are associated with a premature cessation of star formation in some galaxies; in particular, we find no evidence for significantly enhanced star formation in these environments. Simple galaxy formation models predict a quenching of star formation in groups that is too efficient, overpopulating the red sequence. Attempts to fix this by increasing the time-scale of this quenching equally for all group members distort the colour distribution in a way that is inconsistent with observations.

Balogh, Michael L.; McGee, Sean L.; Wilman, Dave; Bower, Richard G.; Hau, George; Morris, Simon L.; Mulchaey, J. S.; Oemler, A., Jr.; Parker, Laura; Gwyn, Stephen



Detection of total and PRRSV-specific antibodies in oral fluids collected with different rope types from PRRSV-vaccinated and experimentally infected pigs  

PubMed Central

Background Oral fluid collected by means of ropes has the potential to replace serum for monitoring and surveillance of important swine pathogens. Until now, the most commonly used method to collect oral fluid is by hanging a cotton rope in a pen. However, concerns about the influence of rope material on subsequent immunological assays have been raised. In this study, we evaluated six different rope materials for the collection of oral fluid and the subsequent detection of total and PRRSV-specific antibodies of different isotypes in oral fluid collected from PRRSV-vaccinated and infected pigs. Results An initial experiment showed that IgA is the predominant antibody isotype in porcine saliva. Moreover, it was found that synthetic ropes may yield higher amounts of IgA, whereas all rope types seemed to be equally suitable for IgG collection. Although IgA is the predominant antibody isotype in porcine oral fluid, the PRRSV-specific IgA-based IPMA and ELISA tests were clearly not ideal for sensitive detection of PRRSV-specific IgA antibodies. In contrast, PRRSV-specific IgG in oral fluids was readily detected in PRRSV-specific IgG-based IPMA and ELISA tests, indicating that IgG is a more reliable isotype for monitoring PRRSV-specific antibody immunity in vaccinated/infected animals via oral fluids with the currently available tests. Conclusions Since PRRSV-specific IgG detection seems more reliable than PRRSV-specific IgA detection for monitoring PRRSV-specific antibody immunity via oral fluids, and since all rope types yield equal amounts of IgG, it seems that the currently used cotton ropes are an appropriate choice for sample collection in PRRSV monitoring. PMID:24938323



[Quantitative evaluation of the genetic divergence of amphibian taxa of different rank by the spectra of total proteins and nonspecific esterases].  


Based on the PAAG disc-electrophoretic spectra of water-soluble total proteins (Pr) and non-specific esterases (Est) from several types of tissues in representatives of Urodela (Triturus vulgaris vulgaris, T. v. lantzi, T. cristatus, T. montandoni, T. dobrogicus) and Anura amphibians (Rana ridibunda, R. lessonae, R. temporaria, R. arvalis; Bufo bufo, B. viridis, Bombina bombina; Xenopus laevis, X. borealis; Hymenochirus boettgeri), mean genetic distances (D = -ln[2i/(2i + d)], where i is the number of fractions identical and d is the number of fractions different by Rf-bands, were estimated within and between taxa of intra-, inter-, and superspecific ranks. The most stable estimates were obtained for Pr and Est spectra of skeletal muscles and eyes. In most cases, the spectra of tissues of the digestive system gave higher D values than those of the other organs. The levels of intraspecific differentiation by D (both Pr and Est) were higher in the studied representatives of the order Urodela, probably due to their lower migration ability and more conservative choice of water-bodies for spawning than in the representatives of the other order; the same trend is true for the interspecific differentiation by Pr spectra. Est, on the contrary, gave lighter interspecific differentiation level in Anura than in Urodela, evidently due to the prevalence of sympatric species pairs able to hybridize among the studied representatives of the latter order. PMID:17484154

Chernyshov, K I; Truveller, K A



Studies on a colony of colour-ringed Herring Gulls Larus argentatus: I. Adult survival rates  

Microsoft Academic Search

Colour-ringed Herring Gulls breeding in a small colony in NE England were used to estimate the average annual adult survival rates of males and females in 6 successive years. Although the female survival rate was higher than that of the males in most years, the difference was not significant. The average annual survival rate for both sexes combined was 91.7%,

J. C. Coulson; J. Butterfield



Optimisation of a three-colour luminescent solar concentrator daylighting system  

Microsoft Academic Search

Electrical power consumption in buildings may be reduced considerably by more efficient use of sunlight for indoor lighting. A stack of luminescent solar concentrator sheets has been developed, which utilises three different coloured fluorescent dyes to produce a concentrated near-white light source to be coupled into flexible polymer sheets and transported up to 10m. Thus in clear sky conditions a

Alan A. Earp; Geoff B. Smith; Jim Franklin; Paul Swift



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



The Optical/Near-IR Colours of Red Quasars  

E-print Network

We present quasi-simultaneous multi-colour optical/near-IR photometry for 157 radio selected quasars, forming an unbiassed sub-sample of the Parkes Flat-Spectrum Sample. Data are also presented for 12 optically selected QSOs, drawn from the Large Bright QSO Survey. The spectral energy distributions of the radio- and optically-selected sources are quite different. The optically selected QSOs are all very similar: they have blue spectral energy distributions curving downwards at shorter wavelengths. Roughly 90% of the radio-selected quasars have roughly power-law spectral energy distributions, with slopes ranging from Fnu=nu^0 to Fnu=nu^-2. The remaining 10% have spectral energy distributions showing sharp peaks: these are radio galaxies and highly reddened quasars. Four radio sources were not detected down to magnitude limits of H ~ 19.6. These are probably high redshift (z >3) galaxies or quasars. We show that the colours of our red quasars lie close to the stellar locus in the optical: they will be hard to identify in surveys such as the Sloan Digital Sky Survey. If near-IR photometry is added, however, the red power-law sources can be clearly separated from the stellar locus: IR surveys such as 2MASS should be capable of finding these sources on the basis of their excess flux in the K-band.

Paul J. Francis; Matthew T. Whiting; Rachel L. Webster



Stochastic spineless expression creates the retinal mosaic for colour vision.  


Drosophila colour vision is achieved by R7 and R8 photoreceptor cells present in every ommatidium. The fly retina contains two types of ommatidia, called 'pale' and 'yellow', defined by different rhodopsin pairs expressed in R7 and R8 cells. Similar to the human cone photoreceptors, these ommatidial subtypes are distributed stochastically in the retina. The choice between pale versus yellow ommatidia is made in R7 cells, which then impose their fate onto R8. Here we report that the Drosophila dioxin receptor Spineless is both necessary and sufficient for the formation of the ommatidial mosaic. A short burst of spineless expression at mid-pupation in a large subset of R7 cells precedes rhodopsin expression. In spineless mutants, all R7 and most R8 cells adopt the pale fate, whereas overexpression of spineless is sufficient to induce the yellow R7 fate. Therefore, this study suggests that the entire retinal mosaic required for colour vision is defined by the stochastic expression of a single transcription factor, Spineless. PMID:16525464

Wernet, Mathias F; Mazzoni, Esteban O; Celik, Arzu; Duncan, Dianne M; Duncan, Ian; Desplan, Claude



Colour transformations for isochrones in the VI-plane  

E-print Network

Reliable temperature-colour transformations are a necessary ingredient for isochrones to be compared with observed colour-magnitude-diagrams of globular clusters. We show that both theoretical and empirical published transformations to (V-I) to a large extend exhibit significant differences between them. Based on these comparisons we argue for particular transformations for dwarfs and giants to be preferred. We then show that our selected combination of transformations results in fits of V-(V-I)-CMDs of a quality which is comparable to that of our earlier V-(B-V) isochrones for a wide range of cluster metallicities. The cluster parameters, such as reddening, are consistent with those derived in (B-V). Therefore, at least in the case of the fit with our own isochrones - based on the particular distance scale provided by our own horizontal branch models, and on the treatment of convection by the mixing-length theory having l/H_p calibrated on our solar model - the chosen transformations appear to lead to self-consistent (V-I) isochrones. Our isochrones are now well tested and self-consistent for B, V and I photometric data.

Achim Weiss; Maurizio Salaris



Changing the colour of light in a silicon resonator  

NASA Astrophysics Data System (ADS)

As the demand for high bandwidths in microelectronic systems increases, optical interconnect architectures are now being considered that involve schemes commonly used in telecommunications, such as wavelength-division multiplexing (WDM) and wavelength conversion. In such on-chip architectures, the ability to perform wavelength conversion is required. So far wavelength conversion on a silicon chip has only been demonstrated using schemes that are fundamentally all-optical, making their integration on a microelectronic chip challenging. In contrast, we show wavelength conversion obtained by inducing ultrafast electro-optic tuning of a microcavity. It is well known that tuning the parameters of an optical cavity induces filtering of different colours of light. Here we demonstrate that it can also change the colour of light. This is an effect often observed in other disciplines, for example, in acoustics, where the sound generated by a resonating guitar string can be modified by changing the length of the strings (that is, the resonators). Here we show this same tuning effect in optics, enabling compact on-chip electrical wavelength conversion. We demonstrate a change in wavelength of up to 2.5 nm with up to 34% on-off conversion efficiency.

Preble, Stefan F.; Xu, Qianfan; Lipson, Michal