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Intraspecific floral colour variation in three Pedicularis species
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作者 Qiu-Yu Zhang Zhe Chen +1 位作者 Hang Sun Yang Niu 《Plant Diversity》 SCIE CAS CSCD 2024年第2期274-279,共6页
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 constanc... 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. 展开更多
关键词 Flower constancy Floral colour variation Plantepollinator interactions Pollinator vision
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Why is the beautyberry so colourful? Evolution,biogeography,and diversification of fruit colours in Callicarpa(Lamiaceae)
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作者 Xing Liu Hui-Min Cai +3 位作者 Wen-Qiao Wang Wei Lin Zhi-Wei Su Zhong-Hui Ma 《Plant Diversity》 SCIE CAS CSCD 2023年第1期6-19,共14页
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 evolutionar... 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. 展开更多
关键词 CALLICARPA Fruit colour PHYLOGENY BIOGEOGRAPHY Dispersal DIVERSIFICATION
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Bare-throated spurfowl(Pternistis spp.)males across Africa impress females with bright throat colours during courtship
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作者 Johann H.van Niekerk 《Avian Research》 SCIE CSCD 2023年第3期416-424,共9页
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 Afr... 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. 展开更多
关键词 Bare-throated spurfowls Breeding colour saturation ORNAMENTS Pternistis spp. Sexual size dimorphism
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Complexity of Injective Homomorphisms to Small Tournaments, and of Injective Oriented Colourings
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作者 Russell J. Campbell Nancy E. Clarke Gary MacGillivray 《Open Journal of Discrete Mathematics》 2023年第1期1-15,共15页
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 homo... 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. 展开更多
关键词 Injective Graph Homomorphism Oriented colouring COMPLEXITY
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Analysis of Students’ Preferences and Engagement with Mobile Games: A Study of Game Assets and Colour Impact
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作者 Venance Saho Zoh Tiémoman Koné Yao Konan 《Open Journal of Applied Sciences》 2023年第12期2211-2222,共12页
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 Digit... 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. 展开更多
关键词 ENGAGEMENT Game Assets colour Mobile Games
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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 被引量:3
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作者 郭育红 《纯粹数学与应用数学》 CSCD 2012年第5期590-594,613,共6页
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.
关键词 分拆恒等式 n—colour有序分拆 组合性质 菲波拉契数
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Colour Reflectance Investigation of Decolourized Sulfur Dyed Cotton Knitted Fabric via Ozone Plasma Treatment
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作者 Yaohui Liu Yanming Wang +2 位作者 Hiu-Yan Cheung Chi-Wai Kan Hong Chua 《World Journal of Engineering and Technology》 2020年第3期429-442,共14页
<div style="text-align:justify;"> Ozone plasma treatment is accessible to be applied on shading adjustment and colour fading because of the capacity of ozone production. It is a green process that trea... <div style="text-align:justify;"> Ozone plasma treatment is accessible to be applied on shading adjustment and colour fading because of the capacity of ozone production. It is a green process that treats dyed cotton fabric under dry condition so as to avoid chemical pollutants. This study means to explore colour reflectance of decolourized sulfur dyed cotton texture using ozone plasma treatment. Sulfur dyed cotton textures with various colour depths (0.5%, 1.5%, 2.5%) were set up to be treated different plasma parameters, including ozone air concentrations (10%, 30%, 50%, 70%), water contents in terms of weight percentage (35%, 45%) of fabric and ozone air plasma treatment periods (10 mins, 20 mins, 30 mins). The colour fading result is assessed by the colour reflectance in percentage (R%) utilizing spectrophotometer under CIE standard illuminant D65. The valid colour fading based on high percentage of reflectance was demonstrated from plasma treatment under higher ozone air concentration (50% and 70% ozone in air) and longer time length of plasma treatment (20 mins and 30 mins). The level of water content contained in the cotton fabrics is appeared to have noteworthy relationship with the degree of decolourization. </div> 展开更多
关键词 Plasma Treatment Cotton Fabric colour Reflectance Sulfur Dye Decolourization
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Induced Co-colouration and Induced Co-decolouration between Different Rare Earths in the System of 《Metal(Ⅱ)-Rare Earth(Ⅲ)-Chromophoric Reagent-Sensitizer》
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作者 陈华序 姚家瑜 齐志刚 《Rare Metals》 SCIE EI CAS CSCD 1992年第1期52-59,共8页
In co-colouration systems of rare earth(Ⅲ) with a metal(Ⅱ), induced colouration and decolouration ef-fects between different rare earths have been discovered. A sensitive co-colouration system of 《Lead(Ⅱ)-RareEar... In co-colouration systems of rare earth(Ⅲ) with a metal(Ⅱ), induced colouration and decolouration ef-fects between different rare earths have been discovered. A sensitive co-colouration system of 《Lead(Ⅱ)-RareEarth(Ⅲ)-Alizarin Violet-Sensitizer》 was chosen as a typical one to study; and neodymium, gadolinium andyttrium were used to represent light, middle and heavy rare earths respectively. Semiquantitative relationshipsfor the induced effects between yttrium and neodymium as well as between gadolinium and neodymium havebeen determined and discussed. In the presence of a sensitizer, these metal ions cannot always be coloured byalizarin violet when each of them is present alone, but a very sensitive co-colouration or co-decolouration mayoccur during their coexistence under certain conditions. If these metals exist as foreign ions in the photometricdetermination of another metal, serious unperceivable interference will possibly occur. Moreover, the condi-tions leading to induced co-colouration and co-decolouration are very complicated, so that close attention mustbe paid to this area in the photometric determination of certain metals. 展开更多
关键词 Rare earth Co-colouration Co-decolouration
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Flavour and Colour of Quarks in Spin Topological Space
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作者 Shaoxu Ren 《Journal of Modern Physics》 2021年第3期380-389,共10页
An assumption that <em>all</em> the six flavour quarks are attributed to be the components of <em>a same, a</em> <em>common</em> isospin multiplets space named <strong>STS<... An assumption that <em>all</em> the six flavour quarks are attributed to be the components of <em>a same, a</em> <em>common</em> isospin multiplets space named <strong>STS</strong> is proposed. Base on <strong>Pauli Exclusion Principle</strong>, every quark is assigned to different flavour marks in STS. Every flavour quark possesses <em>its own colour spectral line array</em> specially appointed. The collection of colour spectral line arrays of the six flavour quarks constructs together the <strong>CSDF</strong>, Colour Spectrum Diagram of Flavour, further baryons and mesons could be constructed from <strong>CSDF</strong>. STS, Spin Topological Space is a math frame with infinite dimensional matrix representation for spin angular momentum. Flavours is an isospin angular momentum coupling phenomena of the three-colour-quarks. 展开更多
关键词 Pauli Exclusion Principle STS Spin Topological Space STC Spin Topological Coordinate colour Spectral Line Array CSDF colour Spectrum Diagram of Flavour
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都用What colour吗?
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作者 姜经志 《中学生英语(初中版)》 2002年第21期12-12,共1页
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:
关键词 “What colour 初中 英语 疑问词 颜色 形容词
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正整数有序分拆的几个计数公式及n-colour有序分拆的一些新的组合性质
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作者 郭育红 《甘肃联合大学学报(自然科学版)》 2010年第1期25-28,共4页
本文首先给出了正整数分别恰含一个奇分部量和一个偶分部量的有序分拆数的计数公式.其次还利用正整数的"偶-奇"无序分拆给出了正整数的n-colour有序分拆的几个新的组合性质.
关键词 有序分拆 n-colour有序分拆 “偶-奇”无序分拆 组合性质
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与n-colour有序分拆相关的两个组合恒等式
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作者 郭育红 夏立华 《甘肃联合大学学报(自然科学版)》 2011年第2期1-3,共3页
给出了正整数ν分拆成m个分部量的n-colour有序分拆数的递推公式,并由这些递推关系得到了两个组合恒等式.
关键词 n-colour有序分拆 递推关系 组合恒等式
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RESEARCH ON FACTORS AFFECTING THE COLOURATION OF RED GLASS-CERAMICS 被引量:1
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作者 赵前 程金树 +1 位作者 王怀德 袁坚 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1996年第3期46-52,共7页
In this pater,effect of alkali oxide, zinc ox-ide and colorants such as cadmiun sulfide and selenium pow-der on the colouration of the red glass-ceramic materials inthe CaO-Al<sub>2</sub>O-3-SiO<sub>... In this pater,effect of alkali oxide, zinc ox-ide and colorants such as cadmiun sulfide and selenium pow-der on the colouration of the red glass-ceramic materials inthe CaO-Al<sub>2</sub>O-3-SiO<sub>2</sub> system has been studied. The relevantlaws have been presented and analysed. 展开更多
关键词 RED GLASS-CERAMICS cadmiun SULFIDE sele-nium POWDER colourATION AGENT
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Effect of Storage Conditions on the Sensory Quality, Colour and Texture of Fresh-Cut Minimally Processed Cabbage with the Addition of Ascorbic Acid, Citric Acid and Calcium Chloride 被引量:2
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作者 Eleni Manolopoulou Theodoros Varzakas 《Food and Nutrition Sciences》 2011年第9期956-963,共8页
The aim of this study was to investigate the effect of storage conditions on the sensory quality, colour and texture of fresh-cut cabbage during the addition of ascorbic acid, citric acid and calcium chloride. Ascorbi... The aim of this study was to investigate the effect of storage conditions on the sensory quality, colour and texture of fresh-cut cabbage during the addition of ascorbic acid, citric acid and calcium chloride. Ascorbic acid maintained the overall quality for 14 days at 0℃ and 7 days at 5℃;no difference, however, was observed regarding browning of cut surface compared to the control sample at both storage temperatures. Calcium chloride maintained the overall quality and cut surface browning for 14 days at both storage temperatures. It was also found that citric acid 1% can be used for minimally processed cabbage. Soaking with citric acid helped retain the color and increased the overall acceptance and organoleptic quality of fresh cut cabbage;it reduced browning of the cut surface and protected against formation of black specks. Citric acid treatment combined with low temperature storage (0℃) prolonged the shelf life of minimally processed cabbage for 22 days, time sufficient for acceptable marketing of the product. The lightness of minimally processed cabbage decreased linearly from 70.94 ± 6 to 63.8 ± 8.5 - 61.3 ± 8 units for the chemical treatments during 22 days of storage at 0℃. Hue angle values during storage time were also significantly influenced by chemical treatments mainly at 0℃. 展开更多
关键词 Storage SENSORY Quality colour Texture FRESH-CUT MINIMALLY Processed CABBAGE Ascorbic ACID Citric ACID and Calcium Chloride
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CLOTHING COLOUR PREFERENCES IN A HOSPITAL ENVIRONMENT IN HONG KONG: PART I - CHILD PATIENT'S PREFERENCES OF COLOUR ON NURSE UNIFORM 被引量:1
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作者 林倚妮 杨国荣 《Journal of China Textile University(English Edition)》 EI CAS 1997年第3期81-88,共8页
The aim of this study explored the importance of colour application on clothing and investigated whether there is a preference of colour on clothing among children under hospital environment. A modified colour associa... The aim of this study explored the importance of colour application on clothing and investigated whether there is a preference of colour on clothing among children under hospital environment. A modified colour associated test based on the Luster Color Test was used to carry out the survey. Fifty child patients aged four to sixteen were asked to look at two specially designed colour cards and to name their preferences and associations on each of the colour. 展开更多
关键词 hospital environment CHILD patients colour PREFERENCES NURSE uniform.
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Colour Metallography of Cast Iron 被引量:2
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作者 Zhou Jiyang Liu Jincheng 《China Foundry》 SCIE CAS 2009年第3期255-267,共13页
This book consists of five sections:Chapter 1 Introduction,Chapter 2 Grey Iron,Chapter 3 Ductile Iron,Chapter 4 Vermicular Cast Iron,and Chapter 5 White Cast Iron. CHINA FOUNDRY publishs this book in several parts ser... This book consists of five sections:Chapter 1 Introduction,Chapter 2 Grey Iron,Chapter 3 Ductile Iron,Chapter 4 Vermicular Cast Iron,and Chapter 5 White Cast Iron. CHINA FOUNDRY publishs this book in several parts serially,starting from the first issue of 2009. 展开更多
关键词 colour Metallography of Cast Iron CAST
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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 被引量:1
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作者 T. LI J. T. GUTHRIE 《Journal of Water Resource and Protection》 2010年第1期77-84,共8页
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 fo... 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. 展开更多
关键词 REACTIVE Azo DYES colour Removal Immobilisation Immobilised Cells
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Improving data hiding within colour images using hue component of HSV colour space 被引量:1
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作者 Fatuma Saeid Hassan Adnan Gutub 《CAAI Transactions on Intelligence Technology》 SCIE EI 2022年第1期56-68,共13页
Data hiding technologies aim to hide the existence of secret information within digital covers such as images by causing unnoticeable degradation to their quality.Reducing the image distortion and increasing the embed... Data hiding technologies aim to hide the existence of secret information within digital covers such as images by causing unnoticeable degradation to their quality.Reducing the image distortion and increasing the embedding capacity are the main points that the data hiding techniques revolved around.This article proposes two high payload embedding methods with high stego image quality using the Hue-Saturation-Value(HSV)colour model.The first method is hue-based embedding(HBE)that employs the H plane for hiding one or two bits in non-grey pixels.The second method uses the three HSV components,so it is called three-planes embedding(TPE).In TPE,one bit is hidden in the least significant bit(LSB)of V of the grey pixels,one or two bits in H of the pixels having low saturation or low brightness and one bit in the LSB of S otherwise.The experiments were conducted on 25 images and the results show that HBE hides more data on average than TPE with its quality reaching 60 dB.TPE achieves quality up to 61 dB and capacity reaches 364 Kb.TPE scores the highest capacity among six state-of-the-art techniques in Red-Green-Blue,HSV,Hue-Saturation-Intensity and YCbCr spaces with the highest average peak signal to noise ratio midst five of them.By embedding 60,90,and 120 Kb,this TPE attains the best average quality amid all the methods. 展开更多
关键词 otherwise colour PAYLOAD
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Synthesis of 1-(4-Antipyrinyl)-3-(3-Chlorophenyl)-Triazene and Its Colour Reaction with Mercury 被引量:1
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作者 Zhi Gang SHE(Departmnt of Pharmacy, Guangdong College of Pharmacy, Guangzhou 510224)Cbu Ru GoNG Yi LUO Ming Hua YANG(Department of Chemistry Hubei Normal University, Huangshi 435002) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,共2页
关键词 RU Antipyrinyl Chlorophenyl Synthesis of 1 Triazene and Its colour Reaction with Mercury
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Fine-mapping and validation of the genomic region underpinning pear red skin colour 被引量:1
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作者 Satish Kumar Chris Kirk +5 位作者 Cecilia Hong Deng Claudia Wiedow Mengfan Qin Richard Espley Jun Wu Lester Brewer 《Horticulture Research》 SCIE 2019年第1期1607-1613,共7页
Red skin colour is an important target trait in various pear breeding programmes.In this study,the genetic control of red skin colour was investigated in an interspecific population derived using the descendants of th... Red skin colour is an important target trait in various pear breeding programmes.In this study,the genetic control of red skin colour was investigated in an interspecific population derived using the descendants of the red sport European pear cultivar‘Max Red Bartlett’(MRB)and the red-blushed Chinese pear cultivar‘Huobali’.Approximately 550 seedlings from nine families were phenotyped for red skin over-colour coverage(Ocolcov)and the intensity of red over-colour(Ocolint)on a 0–9 scale,and genotyped using genotyping-by-sequencing.Genome-wide association analyses were conducted using 7500 high-quality single nucleotide polymorphisms(SNPs).Genomic regions on linkage groups(LG)4 and 5 were found to be associated,and the best SNP(S578_25116)on LG4 accounted for~15%of phenotypic variation in Ocolcov and Ocolint.The association of S578_25116 with Ocolcov and Ocolint was successfully validated in a sample of~200 European and Asian pear accessions.The association with red skin at locus S578_25116 was not present in Asian pear accessions,suggesting its close proximity to the MRB’s Cardinal gene.Several putative candidate genes,including MYB transcription factors(PCP027962 and PCP027967),were identified in the quantitative trait locus region on LG4 and await functional validation. 展开更多
关键词 CULTIVAR breeding colour
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