Intraspecific floral colour variation in three Pedicularis species

Flower constancy describes the phenomenon that pollinators tend to successively visit flowers of a single species during foraging,reducing reproductive interference in natural communities.The extent of flower constancy is largely determined by the floral traits of co-flowering species.Both higher inter-specific and lower intraspecific differences of floral traits should contribute to a higher level of flower constancy.However,previous studies mainly focused on interspecific difference,and the intraspecific variation(consistency)of floral traits received much less attention.We hypothesise that selection may favour lower intraspecific floral trait variation in communities composed of multiple co-flowering congeners.We investigated the floral colour variation of three focal Pedicularis species that share pollinators in 19communities composed of either single or multiple Pedicularis species.Colour was quantified using image-based colour analysis as perceived by pollinators.We found that most of the intrapopulation floral colour variation was below the colour discrimination threshold of bumblebees,implying strongly constrained by the visual selection by pollinators.Contrary to the hypothesis,there is no significant difference in intraspecific floral colour variation between different community contexts.It may be due to the relatively large interspecific floral colour differences of most co-flowering species.The influence of community context on intraspecific variation may be reflected in floral traits other than colours.

Upper bound for the time derivative of entropy for a dynamical system driven by coloured cross-correlated white noises

It is shown how the cross-correlation time and strength of coloured cross-correlated white noises can set an upper bound for the time derivative of entropy in a nonequilibrium system. The value of upper bound can be calculated directly based on the Schwartz inequality principle and the Fokker-Planck equation of the dynamical system driven by coloured cross-correlated white noises. The present calculations can be used to interpret the interplay of the dissipative constant and cross-correlation time and strength of coloured cross-correlated white noises on the upper bound.

Time dependence of entropy flux and entropy production for a dynamical system driven by noises with coloured cross-correlation

This paper shows the Fokker-Planck equation of a dynamical system driven by coloured cross-correlated white noises in the absence and presence of a small external force. Based on the Fokker-Planck equation and the definition of Shannon＇s information entropy, the time dependence of entropy flux and entropy production can be calculated. The present results can be used to explain the extremal behaviour of time dependence of entropy flux and entropy production in view of the dissipative parameter γ of the system, coloured cross-correlation time τ and coloured cross-correlation strength λ.

Colour Removal from Aqueous Solutions of the Reactive Azo Dye Remazol Black B Using the Immobilised Cells (Shewanella Strain J18 143) –Cellulose-g.co-Monomer System

Consideration is given here to colour removal, carried out using immobilised biological cells, Shewanella strain J18 143. In order to provide greater control of an overall colour removal process and to give a basis for the effective recovery of the cell culture species, cell immobilisation has been established on chemically modified cellulose. The modification was achieved by chemically inducing the graft copolymerisation of methacrylic acid onto cotton fabric. The immobilised cells were able to decolorise the dye. The immobilisation methods, physical adsorption, “growing-in” and chemical coupling, were compared. Each of the methods was effective to some extent. However, the latter two immobilisation methods provided the greater effect in decoloration. Each of these immobilised systems is relatively simple to achieve, whether by adsorption, physical interlocking or covalent coupling. The graft copolymer is able to offer versatility in use. The decoloration was shown to be rapid under relatively simple processing conditions. Thus, compared with the established controls, complete decoloration of solutions of Remazol Black B was observed. The potential use of the graft copolymer substrate as support for a biochemical agent was confirmed.

Stochastic resonance in an asymmetric bistable system driven by coloured noises

The phenomenon of stochastic resonance is investigated in an asymmetric bistable system with coloured noises. The approximate Fokker Planck equation is derived based on the Novikov theorem and the Fox approach. By applying the two-state theory, the expression of the signal-to-noise ratio is obtained in the adiabatic limit. The effects of the noise parameters on signal-to-ratio are discussed. It is found that the stochastic resonance phenomena appear in most cases and disappear in some special cases.

Mean first-passage time of an asymmetric bistable system driven by colour-correlated noise

In this paper, the effect of every parameter （including p, q, r, λ, τ） on the mean first-passage time （MFPT） is investigated in an asymmetric bistable system driven by colour-correlated noise. The expression of MFPT has been obtained by applying the steepest-descent approximation. Numerical results show that （1） the intensity of multiplicative noise p and the intensity of additive noise q play different roles in the MFPT of the system, （2） suppression appears on the curve of the MFPT with small λ （e.g. λ 〈 0.5） but there is a peak on the curve of the MFPT when λ is big （e.g. λ 〉 0.5）, and （3） with different values of r （e.g. r = 0.1, 0.5, 1.5）, the effort of τ on the MFPT is diverse.

COLOUR SYSTEMS OF MIXED POLYNUCLEAR COMPLEXES OF LANTHANUM-2,7-BISAZOCHROMOTROPIC ACID DYES-ZINC-O-PHENANTHROLINE

In the preceding work we discussed the formation of mixed polynuclear complexes (MPC) of rare earth-arsenazo Ⅲ-copper-o-phenanthroline. This note reports the action rule of various 2, 7-bisazochromotropic acid dyes with different structures in this kind of colour reactions. The experiments showed that only those symmetric 2, 7-bisazochromotropic

COLOUR-CHANGING MECHANISM IN P_2O_5-Nb_2O_5-Li_2O NONCRYSTALLINE SYSTEM

Raman, IR spectra, RDF and visible spectrum were used to study the glass structure and the valence states of niobium ions in P_2O_5-Nb_2O_5-Li_2O noncrystalling system. The colour-changing mechanism was studied. For 10Nb_2O_5xP_2O_5(90-x)Li_2O (x=40,45,50,55) system glasses, it was known that the glass colout changing from light gold-yellow to blue with increasing is aroused by the Nb^(3+) ion increasing, not by the change of niobium ion coordination.

Colour Features Extraction Techniques and Approaches for Content-Based Image Retrieval (CBIR) System

An image retrieval system was developed purposely to provide an efficient tool for a set of images from a collection of images in the large database that matches the user’s requirements in similarity evaluations such as image content similarity, edge, and colour similarity. Retrieving images based on the contents which are colour, texture, and shape is called content-based image retrieval (CBIR). This paper discusses and describes about the colour features technique for image retrieval systems. Several colour features technique and algorithms produced by the previous researcher are used to calculate the similarity between extracted features. This paper also describes about the specific technique about the colour basis features and combined features (hybrid techniques) between colour and shape features.

Why is the beautyberry so colourful? Evolution,biogeography,and diversification of fruit colours in Callicarpa(Lamiaceae)

Fruit colour is essential to seed dispersal,speciation,and biological diversity in global ecosystems.The relationship between fruit-colour variation and species diversification has long been of interest in evolutionary biology,but remains poorly understood at the genus level.Here,we used Callicarpa,a typical representative of pantropical angiosperm,to analyse whether fruit colours are correlated with biogeographic distribution,dispersal events,and diversification rate.We estimated a time-calibrated phylogeny for Callicarpa and reconstructed ancestral fruit colour.Utilizing phylogenetic methods,we estimated the major dispersal events across the phylogenetic tree and the most likely fruit colours related to each dispersal event,and tested whether the dispersal frequencies and distances of the four fruit colours between major biogeographical areas were equal.We then tested whether fruit colours are correlated with latitude,elevation,and diversification rate.Biogeographical reconstructions showed that Callicarpa originated in the East Asia and Southeast Asia during the Eocene(-35.53 Ma) and diverse species diverged mainly in the Miocene and lasted into the Pleistocene.Large-scale dispersal events were significantly associated with violet-fruited lineages.Furthermore,different fruit colours were markedly correlated with different latitudes and elevations(e.g.,violet fruits were correlated with higher latitudes and elevations;red fruits and black fruits with lower latitudes;white fruits with higher elevations).Notably,violet fruits were statistically associated with highest diversification rates,driving fruit colour variation among different regions globally.Our results contribute to further understanding why fruit colour is so variable at the genus level of angiosperms in different areas around the world.

Bare-throated spurfowl(Pternistis spp.)males across Africa impress females with bright throat colours during courtship

The role of bare body parts in sexual signalling in birds has received relatively little attention.I describe how the bare-throated spurfowl males saturate the colours of their throats to attract females.Of the 23 Afrotropical spurfowl species,the bare-throated subgroup includes Yellow-necked Spurfowl(Pternistis leucosceptus),Rednecked Spurfowl(P.afer),Grey-breasted Spurfowl(P.rufopictus) and Swainson’s Spurfowl(P.swainsonii).The rest of the species include fully feathered throated spurfowls.Throat colour intensity of bare throats was scored using an extensive online digital photographic archive encompassing the four species across the year’s seasons.Each throat(n=836) was assigned to one of four colour-intensity categories to explore the relationship between colour intensities,breeding cycles,and environmental variation.Except for Swainson’s Spurfowl male saturation of throat colours correlated with monthly rainfall,which peaks one or two months before egg laying.Swainson’s Spurfowl peaks during egg laying.Yellow-necked Spurfowl has the largest bare throat.Bare-throated spurfowl males perform an elevated courtship display posture above the female to feature their throat colour.No such displays occur in feather-throated spurfowl.Males with low throat colour saturation harbour more ectoparasites on their bare throats than birds with saturated throats.Male Red-necked Spurfowls have significantly larger bare throats than females.The primary function of bare throats probably assists in thermoregulation,particularly in arid regions.The bare throat may have evolved a secondary role in mating.Yellow-necked,Red-necked,and Greybreasted Spurfowls use their saturated throat colours as ornaments to court females during the breeding season.Unobtrusive female throat colours(unsaturated) may discourage male interlopers and predation during egg laying.Saturation appears to be carotenoid-food based.The different colours among the bare-throated species may serve as prezygotic mechanisms that inhibit cross-breeding and explain why females also have coloured throats.

Complexity of Injective Homomorphisms to Small Tournaments, and of Injective Oriented Colourings

Several possible definitions of local injectivity for a homomorphism of an oriented graph G to an oriented graph H are considered. In each case, we determine the complexity of deciding whether there exists such a homomorphism when G is given and H is a fixed tournament on three or fewer vertices. Each possible definition leads to a locally-injective oriented colouring problem. A dichotomy theorem is proved in each case.

Analysis of Students’ Preferences and Engagement with Mobile Games: A Study of Game Assets and Colour Impact

Mobile games are gaining in popularity among students, although the factors driving engagement remain poorly understood. This study, conducted among 378 students studying for a Bachelor’s degree in Computer and Digital Sciences at the Université Virtuelle de Côte d’Ivoire, explores the influence of game assets and colours on player engagement. Using an online questionnaire, the study identified students’ gaming preferences and their perception of colours. The results show that the key elements most favoured by students are graphics, sound design, the game system, narrative, interactivity and accessibility. What’s more, colour plays a decisive role in their preferences and commitment to educational mobile games.

古代立春节气迎春礼俗纺织品之“青”色探析

纺织品色彩是中国古代二十四节气的重要标志之一,在立春节气中标志性色彩为“青”。通过节气文化和纺织色彩文化挖掘,以及纺织品“青”色界定,为古代色彩体系研究提供更多视角,推动中华传统文化复兴。文章综合古籍梳理迎春官方礼仪和民间礼俗两条发展脉络,探讨了立春古代纺织品色彩范式特征、“青”色释意与现代表达,并提出一种基于现代色彩体系与古代立春青色的对照关系,建立色彩范围。研究发现,纺织品青色是立春迎春礼俗中的标志性色彩,古代“青”在指代纺织品时,以源于天然靛青染成的蓝色为主要色相,在PCCS色彩体系中归类为蓝色、蓝绿色相与饱和度中等、明度中等的色彩特征。

关于正整数有序分拆的一些恒等式和n-colour有序分拆的两个组合性质

研究了正整数的无序分拆与有序分拆的关系.给出了正整数的无序分拆与有序分拆的一些恒等式.并且利用菲波拉契数与正整数n分拆成不含分部量1的有序分拆数的关系给出了n-colour有序分拆的两个组合性质.

岭南四大名园色彩风貌研究

以岭南四大名园(清晖园、余荫山房、梁园、可园)为研究对象,运用孟塞尔(Munsell)国际标准颜色系统,从垂直界面、水平界面和园林特色要素入手,采集色彩数据,对其色彩风貌特征进行研究。结果表明:(1)岭南四大名园在垂直界面上以中明度无彩度灰色和中高明度、中低彩度的黄绿色为主题色,搭配中明度、中低彩度的红色和低明度、极低彩度的红黄色,呈现“沉稳雅致”的色彩风貌特征;(2)水平界面整体呈现“黄绿-赤黄-灰”的色彩序列,呈现“低调清雅”的色彩风貌;(3)园林特色要素色彩作为点缀,呈“鲜绚明快”的特点,对园林气氛起到活跃作用。在此基础上,提出了保护策略,强调历史文脉保留,鼓励社区参与,推动现代技术应用,促进传统与现代色彩的有机交融,以期为岭南园林色彩文脉的传承和发展提供参考,同时为城市色彩的特色塑造提供一定的文化支撑。

都用What colour吗?

英语中表示颜色的形容词很多，同学们学过的有black，red，yellow，blue，white，green，purple，brown，orange，grey等词。由于这些词在句中所作的成分不同，故提问的方式也不同。请看下面三道对划线部分提问的题：

Colour and organic removal of biologically treated coffee curing wastewater by electrochemical oxidation method

The treatment of biologically treated wastewater of coffee-curing industry by the electrochemical oxidation using steel anode was investigated. Bench-scale experiments were conducted for activated sludge process on raw wastewater and the treated effluents were further treated by electrochemical oxidation method for its colour and organic content removal. The efficiency of the process was determined in terms of removal percentage of COD, BOD and colour during the course of reaction. Several operating parameters like time, pH and current density were examined to ascertain their effects on the treatment efficiency. Steel anode was found to be effective for the COD and colour removal with anode efficiency of 0.118 kgCOD\5h -1\5A -1\5m -2 and energy consumption 20.61 kWh\5kg -1 of COD at pH 9. The decrease in pH from 9 to 3 found to increase the anode efficiency from 0.118 kgCOD\5h -1\5A -1\5m -2 to 0.144 kWh\5kg -1 of COD while decrease the energy consumption from 20.61 kWh\5kg -1 of COD to 12.86 kWh\5kg -1 of COD. The pH of 5 was considered an ideal from the present treatment process as it avoids the addition of chemicals for neutralization of treated effluents and also economical with respect to energy consumption. An empirical relation developed for relationship between applied current density and COD removal efficiency showed strong predictive capability with coefficient of determination of 96.5%.

Response of colour and hygroscopic properties of Scots pine wood to thermal treatment

The effect of heat treatment on the surface colour and hygro- scopic properties of pine wood were investigated in this study. Boards of Scots pine wood （Pinus sylvestris L.） were subjected to thermal treatment at 200℃, for 4, 6, and 8 h. The change of equilibrium moisture content and density values of the specimens in order to facilitate the understand- ing of the treated material behavior. The colour parameters L＊ a＊ and b＊, used to depict the total colour change （dE） of wood surface, were shown to change proportionally to the treatment intensity. Moreover, swelling in the tangential and radial directions and absorption of the specimens ap- peared to be enhanced in great extent by the thermal treatment process. The mean value of swelling percentage in the tangential direction de- creased 10.26%, 17.22%, and 19.60% for specimens treated for 4, 6, and 8 h, respectively, referring to the final measurement after 72 h of immer- sion. In radial direction, mean value of swelling percentage decreased 19.56%, 32.75%, and 34.65% for treated for 4, 6 and 8 h, respectively, after 72 h immersion, which attests the decrease in swelling and im- provement in the hygroscopic behavior of Scots pine wood.

Colour stabilities of three types of orthodontic clear aligners exposed to staining agents

The aim of this study was to evaluate and compare the colour stabilities of three types of orthodontic clear aligners exposed to staining agents in vitro. Sixty clear orthodontic aligners produced by three manufacturers （Invisalign, Angelalign, and Smartee） were immersed in three staining solutions （coffee, black tea, and red wine） and one control solution （distilled water）. After 12-h and 7-day immersions, the aligners were washed in an ultrasonic cleaner and measured with a colourimeter. The colour changes （△E＊） were calculated on the basis of the Commission Internationale de I＇Eclairage L＊a＊b＊ colour system （CIE L＊a＊b＊）, and the results were then converted into National Bureau of Standards （NBS） units. Fourier transformation infrared （FT-IR） spectroscopy and scanning electron microscopy （SEM） were conducted to observe the molecular and morphologic alterations to the aligner surfaces, respectively. The three types of aligners exhibited slight colour changes after 12 h of staining, with the exception of the Invisalign aligners stained with coffee. The Invisalign aligners exhibited significantly higher AE＊ values （ranging from 0.30 to 27.81） than those of the Angelalign and Smartee aligners （AE＊ values ranging from 0.33 to 1.89 and 0.32 to 1.61, respectively, P〈O.05）. IFT-IR analysis confirmed that the polymer-based structure of aligners did not exhibit significant chemical differences before and after the immersions. The SEM results revealed different surface alterations to the three types of aligner materials after the 7-day staining. The three types of aesthetic orthodontic appliances exhibited colour stability after the 12-h immersion, with the exception of the Invisalign aligners stained by coffee. The Invisalign aligners were more prone than the Angelalign and Smartee aligners to pigmentation. Aligner materials may be improved by considering aesthetic colour stability properties.