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.

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.

ON f-EDGE COVER-COLOURING OF SIMPLE GRAPHS

An f-edge cover-colouring of a graph G = (V, E) is an assignment of colours to the edges of G such that every colour appears at each vertex v ∈ V at least f(v) times. The maximum number of colours needed to f-edge cover colour G is called the f-edge cover chromatic index of G, denoted by Xfc(G). This paper gives that min[d(v)-1/f(v)]≤xfc(G)≤

Colouring of COVID-19 Affected Region Based on Fuzzy Directed Graphs

Graph colouring is the system of assigning a colour to each vertex of a graph.It is done in such a way that adjacent vertices do not have equal colour.It is fundamental in graph theory.It is often used to solve real-world problems like traffic light signalling,map colouring,scheduling,etc.Nowadays,social networks are prevalent systems in our life.Here,the users are considered as vertices,and their connections/interactions are taken as edges.Some users follow other popular users’profiles in these networks,and some don’t,but those non-followers are connected directly to the popular profiles.That means,along with traditional relationship(information flowing),there is another relation among them.It depends on the domination of the relationship between the nodes.This type of situation can be modelled as a directed fuzzy graph.In the colouring of fuzzy graph theory,edge membership plays a vital role.Edge membership is a representation of flowing information between end nodes of the edge.Apart from the communication relationship,there may be some other factors like domination in relation.This influence of power is captured here.In this article,the colouring of directed fuzzy graphs is defined based on the influence of relationship.Along with this,the chromatic number and strong chromatic number are provided,and related properties are investigated.An application regarding COVID-19 infection is presented using the colouring of directed fuzzy graphs.

A Note on Acyclic Edge Colouring of Star Graph Families

A proper edge colouring f of a graph G is called acyclic if there are no bichromatic cycles in the graph. The acyclic edge chromatic number or acyclic chromatic index, denoted by , is the minimum number of colours in an acyclic edge colouring of G. In this paper, we discuss the acyclic edge colouring of middle, central, total and line graphs of prime related star graph families. Also exact values of acyclic chromatic indices of such graphs are derived and some of their structural properties are discussed.

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 x 7 mm x 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.

Effect of Colouring Process on Pitting Susceptibility of Austenitic Stainless Steel

Colouring of the austenitic stainless steel alloy （20.45% Cr, 8.57% Ni） was carried out in NaNO3-KNO3 eutectic melt without and with additions of Na2O2, NaCl and their mixtures at different temperatures ranging from 400-600℃, under open-circuit and galvanostatic anodic polarization conditions. The produced colours greatly depend on the thickness of oxide films, which in turn depends on the composition of the molten bath and its temperature. The more attractive, bright, adherent and uniform coloured oxide films can be obtained at 400, 450 and 500℃ in molten nitrate bath containing NaCl and Na2O2 mixtures. The pitting corrosion susceptibility of the coloured oxide films was tested in FeCl3 and NaCl as corrosive media. The obtained results indicate that the pitting corrosion susceptibility of the coloured oxide films greatly depends on the previous operating conditions of the colouring process of the stainless steel specimens such as the composition of molten bath, temperature and technique of colouring process.

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.

THE STUDY ON COLOURING MECHANISM OF THE COLOUR-TRANSITION GLAZE

The colour-transition glazed brick has been made under suitable conditions and the expected result has been-obtained.The chemical compositions of the glaze have been given. The structures of Na_2O(K_2O)-CaO(MgO)-Al_2O_3 -SiO_2 system,parent glaze and colour-transition glaze have been invesitigated by SME,Visible spec- trum,IR spectrum and Raman spectrum.A brief exp- lanation to colouring mechanism of colour-transi- tion glaze was given in accordance with theory of optical absorption and scattering. For all specimens,liquid phase separation structures were observed generally be SEM and acomparison between parent glaze and colour-transi- tion glaze was made by Visible specta.Hence an inference can be drawn from these results that the liquid phase droplets contain Nd^(3+),Pr^(3+) ions, which cause coloration selective absorbing and scattering of incident light waves.

Colouring pictures:the First Step to Learn Painting

Many of the primary school students are interested in painting.However, few of them know how to learn painting.Many primary school students think that they can begin their painting by imitating.In fact, the first step to learn painting is to colour the pictures, for you can make the pictures more beautiful by colouring them.Also, you can feel how the pictures were drawn by colouring them.

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.

“Water-Colouring” and Geomorphologic Features of the Marl Hills in Changing Quality of Soil and Water

Water scarcity has always been one of the most important obstacles in the process of agricultural development in arid and low-rainfall climates. In farming, the water quality also plays an important role;as the poor quality of water can be one of the limiting factors in this sector that in addition to the agricultural problems has also caused soil problems. In this paper, we introduce and study an indigenous method of water conservation and soil protection in the east of Iran termed as “water-colouring” and the role of geomorphologic features of marl hills in one of the rivers located in the southern slopes of the Joghtay Mountain (Kalateh-Sadat Watershed). In this study, field observation, sampling and analysis of water and sediment, physicochemical experiments, SPSS software for statistical analysis and satellite images have been used to produce digital models. Finally, the effects of muddy water and clear water have been compared in terms of chemical quality and productivity of agricultural land. The results show that the method of water-colouring is the best indigenous-economical method for moisture retention and regeneration of the agricultural land soil. Given the statistical reasons and studying the other researches in this field, water-colouring causes change texture and soil composition, fertility of agricultural land and reduce the losses due to evaporation and infiltration.

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.

谷子籽粒类黄酮含量和粒色的QTL定位

谷子(Setaria italica L.)是我国北方地区重要的粮食作物,籽粒营养丰富,且富含多种类黄酮物质,对生长发育和品质形成发挥着重要作用。目前谷子籽粒类黄酮合成及粒色形成相关调控机制研究较少。分析谷子类黄酮含量及粒色性状相关的QTL,为类黄酮合成关键基因的精细定位、克隆及功能研究奠定基础,同时,也为揭示谷子类黄酮合成及代谢机制和培育富含类黄酮谷子品种提供技术支撑。本研究以红粒色高类黄酮品种金苗红酒谷和黄粒色低类黄酮品种豫谷28为亲本构建的包含150个家系的重组自交系(RIL)群体为试验材料,在谷子成熟期对籽粒粒色和类黄酮含量相关性状进行分析。同时,采用复合区间作图法(composite interval mapping,CIM)对粒色和类黄酮含量进行QTL定位与分析,并对QTL置信区间内的候选基因进行预测。相关性分析表明,类黄酮含量与粒色呈显著正相关。共定位到4个与类黄酮含量相关和11个与粒色相关的QTL,分别位于1号、2号、5号、6号、7号、8号和9号染色体上,单个QTL的表型贡献率为2.01%~29.25%,6个为主效QTL,其中,qSC1-2和qFLA1-1、qSC7-1和qFLA7-1、qSC9-3和qFLA9-1为2个性状下共同定位到的QTL。通过基因预测与功能注释,筛选出QTL置信区间内5个与类黄酮物质合成及代谢相关的候选基因,表明类黄酮物质的合成、代谢及利用相关基因极有可能控制了这些基因的表达。15个QTL分别聚集于7条染色体上,基于基因功能注释,共筛选了5个与谷子类黄酮合成及代谢相关的候选基因,表明不同QTL位点参与到了共同遗传机制,并可通过分子标记辅助选择进行类黄酮合成及代谢等有利基因的聚合育种。

云南短头熊蜂体色模式多态性地理分布格局

【目的】熊蜂是自然环境中一类重要的传粉昆虫,其体表通常覆盖着颜色鲜亮的体毛,从而形成明显的体色模式。本研究旨在探明云南短头熊蜂Bombus breviceps体色模式多态性的地理分布格局,为熊蜂遗传进化及环境适应性研究提供基础数据。【方法】通过检视2017-2021年在云南和贵州共127个采样点采集的957头短头熊蜂标本[包括雌成蜂898头(蜂王103头、工蜂795头)以及雄成蜂59头],绘制雌、雄成蜂体色模式图,分析体色模式的类型及优势度。基于不同体节的体色组成对体色模式进行系统聚类,基于经纬度0.5°×0.5°单元格内体色类群组成分析云南短头熊蜂体色模式的地理分布格局。【结果】短头熊蜂胸部背板体毛的颜色在黑色、灰黄色和橙黄色间过渡变化,腹部背板体毛颜色有黑色、灰黄色、黄色和深棕色,腹部第1背板体毛均为黄色,黄色体毛由第1背板向后逐节延伸最多至第3背板的整节,第2,3背板的体毛为黄色、黑色或灰黄色,而深棕色体毛由腹部第6背板向前逐节延伸最多至第3背板的下半节;雌成蜂有81种体色模式,其中工蜂有80种,蜂王有13种,其中12种与工蜂相同,雄成蜂有37种体色模式,其中28种与雌成蜂相似。雌成蜂的81种体色模式中,优势体色模式有2种,丰盛体色模式有5种,常见体色模式有10种,稀少体色模式有64种。雌成蜂体色模式可聚为3个体色类群,即:A类群(黑胸棕尾),B-1类群(橙胸黑尾)和B-2类群(橙胸棕尾)。云南短头熊蜂体色模式的地理分布可划分为云南高原西部(Ⅰ)和云南高原东部(Ⅱ)2个大区。Ⅰ区进一步可分为滇中亚热带高原区(Ⅰ1)和滇西南热带低山宽谷区(Ⅰ2);Ⅱ区进一步可分为滇东南亚热带岩溶山地河谷区(Ⅱ1)和滇东北亚热带中山河谷区(Ⅱ2)。A体色类群仅分布于Ⅰ1小区,Ⅰ2小区仅有B-2类群分布,而B-1类群仅分布于Ⅱ区,且同域分布有B-2类群。体色模式多态性高低与分布地经纬度无明显相关性,云南高原中部24.00°-24.50°N,102.50°-103.00°E方格内的体色模式多态性最高,达18种;A体色类群分布地平均海拔[(1951±311)m]极显著高于B-1[(1568±352)m]和B-2[(1556±534)m]类群分布地平均海拔。【结论】云南短头熊蜂体色模式多态性丰富,可划分为3个主要的体色类群,其地理分布与气候区划、地型地貌和土地利用类型相关,地理区划特征明显,同区域内体色模式多态性向优势模式趋同。本研究结果对深入挖掘中国本土熊蜂资源和物种多样性保护具有重要意义,为不同生境利用与发展熊蜂提供技术支撑。

牙齿漂白技术的临床应用策略

牙齿漂白技术是微创治疗牙齿着色的有效方法之一。漂白技术实施简单,但是临床应用中颇具挑战性。术前进行充分的医患沟通和评估,根据病因和难度制定个性化方案,对于治疗中可能出现的问题进行有计划地防控,是治疗取得成功的关键。本文结合文献回顾和笔者的临床体会,对活髓牙漂白技术的临床策略进行探讨,以期为着色牙的漂白治疗提供参考。

色纺纱用黏胶纤维的连续染色工艺与染色性能

采用散纤维连续染色技术对黏胶散纤维进行连续浸渍染色后再冷堆固色,然后进行连续式水洗。分析了固色时间对黏胶纤维外观形貌、色泽指标及力学性能的影响,并对染色黏胶纤维成品的色牢度、pH和甲醛含量进行测试。结果表明:连续浸渍染色后的黏胶纤维,经冷堆24 h固色后,可获得较好的匀染性;染色黏胶纤维的力学性能略有下降,其中强度下降约15%,断裂伸长率下降约16%;染色黏胶纤维的各项色牢度、pH和甲醛含量均符合要求。

饲料中添加β-胡萝卜素对肝胰腺白化症扣蟹生长性能的影响

开展了饲料中添加藻源天然β-胡萝卜素对肝胰腺白化症扣蟹的生长性能的影响试验。在基础饲料中添加不同水平的杜氏盐藻,配制成2组饲料,分别为Diet 2和Diet 3,对应β-胡萝卜素含量分别为100和200 mg/kg,不添加杜氏盐藻的饲料组为对照组Diet 1。结果表明,Diet 2和Diet 3组显著提高了肝胰腺白化扣蟹的质量增加率及成活率(P<0.05),显著增加了扣蟹肝胰腺指数、肝胰腺总脂含量(P<0.05),以及肝胰腺中总类胡萝卜素、虾青素和β-胡萝卜素含量。Diet 1、Diet 2和Diet3组扣蟹肝胰腺中粗蛋白及灰分含量差异较小;蟹肝胰腺红度值a*及黄度值b*均随着饲料中杜氏盐藻的增加而显著增加。指出,饲料中添加藻源β-胡萝卜素,在一定程度上改善了扣蟹的肝胰腺白化症状。

基于CycleGAN算法的凤翔木版年画色彩特征迁移研究

目的为传承保护和创新发展陕西地区非物质文化遗产——凤翔木版年画,解决传统手工艺色彩复原难、图案组合创新效率低等问题,通过生成对抗网络与凤翔木版年画结合的方式,多维度推动其发展。方法通过高清扫描、自适应阈值检测法、标准色值提取及数据增广等方式对其进行系统性归纳总结与标准化采集存储,建立凤翔木版年画数据集,利用CycleGAN算法训练网络模型以完成迁移实验。结果通过艺术与技术的结合,不仅完成了年画墨线稿的色彩复原,还完成了创新设计图案的快速着色。结论在凤翔木版年画的史料复原与设计应用方面,通过现代设计方法与色彩风格迁移功能的结合,使其在适应现代发展趋势、完成活态传承任务的同时,为同类研究提供新思路。

贺兰山东麓红葡萄酒颜色差异分析

为探究贺兰山东麓地区赤霞珠及梅鹿辄葡萄酒的颜色特征差异,以贺兰山东麓5个地区的‘赤霞珠’及‘梅鹿辄’葡萄为实验材料,测定其CIELAB色空间参数、酚类物质含量,并进行主成分分析。结果表明,贺兰山东麓葡萄酒CIELAB参数受品种及地区影响显著,具有较低的L^(*),而a^(*)、b^(*)较高,葡萄酒颜色较暗,红色色调较高;C^(*)_(ab)为47.46~60.82,酒样色彩饱和性较高。不同地区和不同品种的干红葡萄酒在颜色相关指标的主成分图上分布差异显著。金山赤霞珠葡萄酒的L^(*)、a^(*)等CIE参数均显著低于其他酒样,而花色苷、总黄酮等酚类物质显著高于其他酒样,酒体呈暗紫红色,明显区别于其他地区;玉泉营梅鹿辄葡萄酒的b^(*)、h_(ab)较低,总花色苷显著高于其他酒样,酒体明亮,呈胭脂红色。各地葡萄酒颜色差异显著,具有各自特有的颜色特征。