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An Improved Interval-Valued Picture Fuzzy TOPSIS Approach Based on New Divergence Measures for Risk Assessment
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作者 Sijia Zhu Yuhan Li +3 位作者 Prasanalakshmi Balaji Akila Thiyagarajan Rajanikanth Aluvalu Zhe Liu 《Computer Modeling in Engineering & Sciences》 2025年第8期2099-2121,共23页
While interval-valued picture fuzzy sets(IvPFSs)provide a powerful tool for modeling uncertainty and ambiguity in various fields,existing divergence measures for IvPFSs remain limited and often produce counterintuitiv... While interval-valued picture fuzzy sets(IvPFSs)provide a powerful tool for modeling uncertainty and ambiguity in various fields,existing divergence measures for IvPFSs remain limited and often produce counterintuitive results.To address these shortcomings,this paper introduces two novel divergencemeasures for IvPFSs,inspired by the Jensen-Shannon divergence.The fundamental properties of the proposed measures-non-degeneracy,symmetry,triangular inequality,and boundedness-are rigorously proven.Comparative analyses with existing measures are conducted through specific cases and numerical examples,clearly demonstrating the advantages of our approach.Furthermore,we apply the new divergence measures to develop an enhanced interval-valued picture fuzzy TOPSIS method for risk assessment in construction projects,showing the practical applicability and effectiveness of our contributions. 展开更多
关键词 Interval-valued picture fuzzy sets divergence measure Jensen-Shannon divergence TOPSIS risk assessment
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Bayesian Network Reconstruction and Iterative Divergence Problem Solving Method Based on Norm Minimization
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作者 Kuo Li Aimin Wang +2 位作者 Limin Wang Yuetan Zhao Xinyu Zhu 《Computer Modeling in Engineering & Sciences》 2025年第4期617-637,共21页
A Bayesian network reconstruction method based on norm minimization is proposed to address the sparsity and iterative divergence issues in network reconstruction caused by noise and missing values.This method achieves... A Bayesian network reconstruction method based on norm minimization is proposed to address the sparsity and iterative divergence issues in network reconstruction caused by noise and missing values.This method achieves precise adjustment of the network structure by constructing a preliminary random network model and introducing small-world network characteristics and combines L1 norm minimization regularization techniques to control model complexity and optimize the inference process of variable dependencies.In the experiment of game network reconstruction,when the success rate of the L1 norm minimization model’s existence connection reconstruction reaches 100%,the minimum data required is about 40%,while the minimum data required for a sparse Bayesian learning network is about 45%.In terms of operational efficiency,the running time for minimizing the L1 normis basically maintained at 1.0 s,while the success rate of connection reconstruction increases significantly with an increase in data volume,reaching a maximum of 13.2 s.Meanwhile,in the case of a signal-to-noise ratio of 10 dB,the L1 model achieves a 100% success rate in the reconstruction of existing connections,while the sparse Bayesian network had the highest success rate of 90% in the reconstruction of non-existent connections.In the analysis of actual cases,the maximum lift and drop track of the research method is 0.08 m.The mean square error is 5.74 cm^(2).The results indicate that this norm minimization-based method has good performance in data efficiency and model stability,effectively reducing the impact of outliers on the reconstruction results to more accurately reflect the actual situation. 展开更多
关键词 Bayesian norm minimization network reconstruction iterative divergence SPARSITY
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A Unified Parametric Divergence Operator for Fermatean Fuzzy Environment and Its Applications in Machine Learning and Intelligent Decision-Making
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作者 Zhe Liu Sijia Zhu +5 位作者 Yulong Huang Tapan Senapati Xiangyu Li Wulfran Fendzi Mbasso Himanshu Dhumras Mehdi Hosseinzadeh 《Computer Modeling in Engineering & Sciences》 2025年第11期2157-2188,共32页
Uncertainty and ambiguity are pervasive in real-world intelligent systems,necessitating advanced mathematical frameworks for effective modeling and analysis.Fermatean fuzzy sets(FFSs),as a recent extension of classica... Uncertainty and ambiguity are pervasive in real-world intelligent systems,necessitating advanced mathematical frameworks for effective modeling and analysis.Fermatean fuzzy sets(FFSs),as a recent extension of classical fuzzy theory,provide enhanced flexibility for representing complex uncertainty.In this paper,we propose a unified parametric divergence operator for FFSs,which comprehensively captures the interplay among membership,nonmembership,and hesitation degrees.The proposed operator is rigorously analyzed with respect to key mathematical properties,including non-negativity,non-degeneracy,and symmetry.Notably,several well-known divergence operators,such as Jensen-Shannon divergence,Hellinger distance,andχ2-divergence,are shown to be special cases within our unified framework.Extensive experiments on pattern classification,hierarchical clustering,and multiattribute decision-making tasks demonstrate the competitive performance and stability of the proposed operator.These results confirm both the theoretical significance and practical value of our method for advanced fuzzy information processing in machine learning and intelligent decision-making. 展开更多
关键词 Fermatean fuzzy sets divergence operator pattern classification hierarchical clustering multiattribute decision-making
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Chloroplast genome characterization and divergence time estimation of Persicaria capitata
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作者 Xianfa Zeng Chang Liu +6 位作者 Xiaoying Yang Xinyue Wang Jiangli Luo Ying Zhou Liyan Zhang Zengjie Gao Xiang Pu 《Acupuncture and Herbal Medicine》 2025年第1期89-102,共14页
Objective:With Persicaria capitata as test materials,we compared and analyzed the chloroplast(cp)genome characteristics as well as their phylogenetic relationships and evolutionary history with related species of Pers... Objective:With Persicaria capitata as test materials,we compared and analyzed the chloroplast(cp)genome characteristics as well as their phylogenetic relationships and evolutionary history with related species of Persicaria nepalensis,Persicaria japonica,Persicaria chinensis,Persicaria filiformis,Persicaria perfoliata,Persicaria pubescens,Persicaria hnydropiper.Methods:The Illumina HiSeq high-throughput sequencing platform was used for the first time for P.capitata cp genome sequencing.NOVOPlasty and CpGAVAS2 were used for assembly and annotation,and Codon W,DnaSP,and MISA were used to conduct a series of comparative genomic analyses between the plant and seven species of the same genus.A phylogenetic tree was constructed using the maximum likelihood(ML)and neighbor-joining(NJ)methods,and divergence time was estimated using BEAST.Results:The total length of P.capitata cp genome was 158,821 bp,with a guanine and cytosine(GC)content of 38.0%,exhibiting a typical circular tetrad structure.The genome contains 127 annotated genes,including 82 protein-coding and 45 tRNA-encoding genes.The cp genome harbors simple sequence repeat(SSR)loci primarily composed of A/T.The conserved species structure of this genus is reinforced by the expansion and contraction of the inverted repeat(IR)region.The non-coding regions of the cp genomes exhibited significant differences among the genera.Six different mutation hotspots(psbK-psbI,atpI-rps2,petN-psbD,atpB-rbcL,cemA-petA,ndhI-ndhA-ycf1)were screened from the non-coding regions of genes with high nucleotide variability(pI).These hotspots were expected to define the phylogenetic species of Persicaria.Furthermore,phylogenetic analysis of Polygonaceae plants showed that P.capitata was more closely related to P.chinensis than P.nepalensis.Analysis of divergence time indicated that Polygonaceae originated in the Late Cretaceous(~180 Ma)and began to differentiate during the Middle Miocene.Persicaria differentiated~66.44 million years ago,during the Miocene.Conclusions:Our findings will serve as a scientific basis for further research on species identification and evolution,population genetics,and phylogenetic analysis of P.capitata.Further,we provide valuable information for understanding the origin and evolution of Persicaria in Polygonaceae and estimating the differentiation time of Persicaria and its population. 展开更多
关键词 Chloroplast genomes Comparative analysis divergence time Persicaria capitata Phylogenetic relationship
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Development of AHP-Based Divergence Distance Measure between P,q,r-Spherical Fuzzy Sets with Applications in Multi-Criteria Decision Making
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作者 Shah Zeb Khan Muhammad Rahim +3 位作者 Adel M.Widyan A.Almutairi Njood Shaher Ethaar Almutire Hamiden Abd El-Wahed Khalifa 《Computer Modeling in Engineering & Sciences》 2025年第5期2185-2211,共27页
This study introduces a novel distance measure(DM)for(p,q,r)-spherical fuzzy sets((p,q,to improve decision-making in complex and uncertain environments.Many existing distance measures eitherr)-SFSs)fail to satisfy ess... This study introduces a novel distance measure(DM)for(p,q,r)-spherical fuzzy sets((p,q,to improve decision-making in complex and uncertain environments.Many existing distance measures eitherr)-SFSs)fail to satisfy essential axiomatic properties or produce unintuitive outcomes.To address these limitations,we propose a new three-dimensional divergence-based DM that ensures mathematical consistency,enhances the discrimination of information,and adheres to the axiomatic framework of distance theory.Building on this foundation,we construct a multi-criteria decision-making(MCDM)model that utilizes the proposed DM to evaluate and rank alternatives effectively.The applicability and robustness of the model are validated through a practical case study,demonstrating that it leads to more rational,consistent,and reliable decision outcomes compared to existing approaches. 展开更多
关键词 p q r-spherical fuzzy sets divergence distance measures AHP decision making
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Divergences in neuroendocrine prostate cancer frequency as recognized by anatomic pathologists,clinicians,and basic scientists
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作者 Kenneth A Iczkowski Mamta Parikh 《Asian Journal of Andrology》 2025年第1期1-3,共3页
As a practicing anatomic pathologist specialized in urologic pathology,a vast difference may be observed between what pathologists designate as neuroendocrine(or small cell)carcinoma of the prostate,and what clinician... As a practicing anatomic pathologist specialized in urologic pathology,a vast difference may be observed between what pathologists designate as neuroendocrine(or small cell)carcinoma of the prostate,and what clinicians or basic scientists define as such. 展开更多
关键词 urologic pathology anatomic pathologists CLINICIANS neuroendocrine prostate cancer basic scientists divergenceS anatomic pathologist
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THE DIVERGENCE-CONVERGENCE EFFECT OF SURFACE CURRENT AND ITS ACTION ON THE BOHAI SEA
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作者 赵进平 侍茂崇 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1993年第2期135-142,共8页
The action of the wind field and the influence of topography can cause divergence or convergence of surface current. The existence of the divergence-convergence effect is proved and the dynamical significance of the d... The action of the wind field and the influence of topography can cause divergence or convergence of surface current. The existence of the divergence-convergence effect is proved and the dynamical significance of the divergent or convergent state and its link with many marine phenomena are pointed out. Divergence fields of surface current in the Bohai Sea in winter and summer are obtained by numerical modelling describing the divergence-convergence character of seasonally wind-driven current. The relation between the effect and seasonal marine phenomena is discussed. Study on the divergence-convergence effect of surface current (DCESC)can be an indirect method for testing the calculated results. 展开更多
关键词 divergence divergence-convergence effect SURFACE CURRENT the Bohai SEA 3-dimension model
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Genetically-and environmentally-dependent processes drive interspecific and intraspecific divergence in the Chinese relict endemic genus Dipteronia
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作者 Tao Zhou Xiaodan Chen +6 位作者 Jordi López-Pujol Guoqing Bai Sonia Herrando-Moraira Neus Nualart Xiao Zhang Yuemei Zhao Guifang Zhao 《Plant Diversity》 SCIE CAS CSCD 2024年第5期585-599,共15页
China is a hotspot of relict plant species that were once widespread throughout the Northern Hemisphere.Recent research has demonstrated that the occurrence of long-term stable refugia in the mountainous regions of ce... China is a hotspot of relict plant species that were once widespread throughout the Northern Hemisphere.Recent research has demonstrated that the occurrence of long-term stable refugia in the mountainous regions of central and south-western China allowed their persistence through the late Neogene climate fluctuations.One of these relict lineages is Dipteronia,an oligotypic tree genus with a fossil record extending to the Paleocene.Here,we investigated the genetic variability,demographic dynamics and diversification patterns of the two currently recognized Dipteronia species(Dipteronia sinensis and D.dyeriana).Molecular data were obtained from 45 populations of Dipteronia by genotyping three cpDNA regions,two single copy nuclear genes and 15 simple sequence repeat loci.The genetic study was combined with niche comparison analyses on the environmental space,ecological niche modeling,and landscape connectivity analysis.We found that the two Dipteronia species have highly diverged both in genetic and ecological terms.Despite the incipient speciation processes that can be observed in D.sinensis,the occurrence of long-term stable refugia and,particularly,a dispersal corridor along Daba Shan-west Qinling,likely ensured its genetic and ecological integrity to date.Our study will not only help us to understand how populations of Dipteronia species responded to the tectonic and climatic changes of the Cenozoic,but also provide insight into how Arcto-Tertiary relict plants in East Asia survived,evolved,and diversified. 展开更多
关键词 Dipteronia Interspecific/intraspecific divergence Genetic structure Climatic niche divergence Dispersal corridor
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Molecular evolution and functional divergence of HAK potassium transporter gene family in rice(Oryza sativa L.) 被引量:25
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作者 Zefeng Yang Qingsong Gao +3 位作者 Changsen Sun Wenjuan Li Shiliang Gu Chenwu Xu 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2009年第3期161-172,共12页
The high-affinity K+ (HAK) transporter gene family is the largest family in plant that functions as potassium transporter and is important for various aspects of plant life. In the present study, we identified 27 m... The high-affinity K+ (HAK) transporter gene family is the largest family in plant that functions as potassium transporter and is important for various aspects of plant life. In the present study, we identified 27 members of this family in rice genome. The phylogenetic tree divided the land plant HAK transporter proteins into 6 distinct groups. Although the main characteristic of this family was established before the origin of seed plants, they also showed some differences between the members of non-seed and seed plants. The HAK genes in rice were found to have expanded in lineage-specific manner after the split of monocots and dicots, and both segmental duplication events and tandem duplication events contributed to the expansion of this family. Functional divergence analysis for this family provided statistical evidence for shifted evolutionary rate after gene duplication. Further analysis indicated that both point mutant with positive selection and gene conversion events contributed to the evolution of this family in rice. 展开更多
关键词 HAK potassium transporter gene family RICE functional divergence gene conversion positive selection
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Tunable 3D Nanofiber Architecture of Polycaprolactone by Divergence Electrospinning for Potential Tissue Engineering Applications 被引量:8
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作者 George Z.Tan Yingge Zhou 《Nano-Micro Letters》 SCIE EI CAS 2018年第4期314-323,共10页
The creation of biomimetic cell environments with micro and nanoscale topographical features resembling native tissues is critical for tissue engineering. To address this challenge, this study focuses on an innovative... The creation of biomimetic cell environments with micro and nanoscale topographical features resembling native tissues is critical for tissue engineering. To address this challenge, this study focuses on an innovative electrospinning strategy that adopts a symmetrically divergent electric field to induce rapid self-assembly of aligned polycaprolactone(PCL) nanofibers into a centimeter-scale architecture between separately grounded bevels. The 3D microstructures of the nanofiber scaffolds were characterized through a series of sectioning in both vertical and horizontal directions. PCL/collagen(type I)nanofiber scaffolds with different density gradients were incorporated in sodium alginate hydrogels and subjected to elemental analysis. Human fibroblasts were seeded onto the scaffolds and cultured for 7 days. Our studies showed that the inclination angle of the collector had significant effects on nanofiber attributes, including the mean diameter, density gradient, and alignment gradient. The fiber density and alignment at the peripheral area of the 45°-collector decreased by 21% and 55%, respectively, along the z-axis,while those of the 60°-collector decreased by 71% and 60%, respectively. By altering the geometry of the conductive areas on the collecting bevels, polyhedral and cylindrical scaffolds composed of aligned fibers were directly fabricated. By using a four-bevel collector, the nanofibers formed a matrix of microgrids with a density of 11%. The gradient of nitrogen-to-carbon ratio in the scaffold-incorporated hydrogel was consistent with the nanofiber density gradient. The scaffolds provided biophysical stimuli to facilitate cell adhesion, proliferation, and morphogenesis in 3D. 展开更多
关键词 divergence electrospinning 3D nanofiber scaffold Tissue engineering Microstructure gradient
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Genetic variability and divergence studies in pod and seed traits of Pongamia pinnata(L.) Pierre., accessions in Bay Islands 被引量:4
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作者 I. Jaisankar M. Sankaran +1 位作者 D.R. Singh V. Damodaran 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第2期351-358,共8页
In this study, we assessed the variability in pod, seed traits and oil content of 24 accessions of Pongamia pinnata collected from different parts of the Andaman and Nicobar Islands, India. The experiment was conducte... In this study, we assessed the variability in pod, seed traits and oil content of 24 accessions of Pongamia pinnata collected from different parts of the Andaman and Nicobar Islands, India. The experiment was conducted at the Central Agricultural Research Institute, Port Blair during 2010 to 2011. The variability studies for pod and seed traits revealed that, the accession CPT-6 collected from New Wandoor in South Andaman recorded the maximum values for eight traits viz. pod length (75.51 mm), pod width (34.62 mm), pod thickness (17.55 mm), 100 pod weight (770.33 g), seed width (21.23 mm), 100 seed weight (377.00 g), oil percentage (43.92%) and germination percentage (94.7%). However, the maximum seed length (26.46 mm) was recorded from CPT 2 and the maximum pod-seed ratio was obtained from CPT 13 and CPT 4 (2.50 and 2.44 respectively). The phenotypic and genotypic coefficients of variations were also close to each other for all traits, but the 100 pod and seed weight exhibited higher phenotypic and genotypic coefficient of variation than the other traits. Estimates of broad sense heritability ranged from 0.30 (for seed length) to 0.95 (pod length) and genetic ad- vance as percent of the mean ranged between 11.66% and 57.40% with seed length giving the lowest value and 100 pod weight giving the high- est value. Both the phenotypic and genotypic correlation between pod length, pod width, pod thickness, 100 pod weight, seed width and 100 seed weight and between pod thickness, 100 pod weight, seed width, 100 seed weight and germination percentage were found to be strong. On the basis of non hierarchical Euclidian cluster analysis, 24 accessions were grouped into six clusters. The maximum numbers of seven accessions were included in cluster VI. The maximum intra cluster distance (10.238)shown by cluster VI and the maximum inter cluster distance (17.021) between V and HI followed by III and II (15.942). Among the six clus- ters formed the cluster III recorded maximum oil percentage, 100 pod weight, 100 seed ,weight, pod length, pod thickness, pod width, seed width and. germination percentage, while cluster V recorded maximum pod seed ratio and germination percentage. The present findings suggest that the crossing between accessions of cluster V and cluster III will result in a wide spectrum of variability in subsequent generations. 展开更多
关键词 Pongamia pinnata correlation heritabi!ity genetic gain genetic divergence oil percentage
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Gapless genome assembly of azalea and multi-omics investigation into divergence between two species with distinct f lower color 被引量:6
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作者 Shuai Nie Shi-Wei Zhao +15 位作者 Tian-Le Shi Wei Zhao Ren-Gang Zhang Xue-Chan Tian Jing-Fang Guo Xue-Mei Yan Yu-Tao Bao Zhi-Chao Li Lei Kong Hai-Yao Ma Zhao-Yang Chen Hui Liu Yousry AEl-Kassaby Ilga Porth Fu-Sheng Yang Jian-Feng Mao 《Horticulture Research》 SCIE CSCD 2023年第1期193-206,共14页
The genus Rhododendron(Ericaceae),with more than 1000 species highly diverse in f lower color,is providing distinct ornamental values and a model system for f lower color studies.Here,we investigated the divergence be... The genus Rhododendron(Ericaceae),with more than 1000 species highly diverse in f lower color,is providing distinct ornamental values and a model system for f lower color studies.Here,we investigated the divergence between two parental species with different f lower color widely used for azalea breeding.Gapless genome assembly was generated for the yellow-f lowered azalea,Rhododendron molle.Comparative genomics found recent proliferation of long terminal repeat retrotransposons(LTR-RTs),especially Gypsy,has resulted in a 125 Mb(19%)genome size increase in species-specific regions,and a significant amount of dispersed gene duplicates(13402)and pseudogenes(17437).Metabolomic assessment revealed that yellow f lower coloration is attributed to the dynamic changes of carotenoids/f lavonols biosynthesis and chlorophyll degradation.Time-ordered gene co-expression networks(TO-GCNs)and the comparison confirmed the metabolome and uncovered the specific gene regulatory changes underpinning the distinct f lower pigmentation.B3 and ERF TFs were found dominating the gene regulation of carotenoids/f lavonols characterized pigmentation in R.molle,while WRKY,ERF,WD40,C2H2,and NAC TFs collectively regulated the anthocyanins characterized pigmentation in the red-f lowered R simsii.This study employed a multi-omics strategy in disentangling the complex divergence between two important azaleas and provided references for further functional genetics and molecular breeding. 展开更多
关键词 divergence YELLOW COLLECTIVE
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Extensive genetic divergence among Diptychus maculatus populations in northwest China 被引量:3
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作者 孟玮 杨天燕 +5 位作者 海萨 马燕武 蔡林钢 马徐发 高天翔 郭焱 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第3期577-584,共8页
D. maculates is a kind of specialized Schizothoracinae fish has been locally listed as a protected animal in Xinjiang Province, China. Ill River located in north of Tianshan Mountain and Tarim River located in north o... D. maculates is a kind of specialized Schizothoracinae fish has been locally listed as a protected animal in Xinjiang Province, China. Ill River located in north of Tianshan Mountain and Tarim River located in north of Qinghai-Tibetan Plateau were two main distribution areas of this fish. To investigate the genetic diversity and genetic structure ofD. maculates, four populations from Tarim River system and two populations from Ili River system were collected in this study. A 570-bp sequence of the control region was obtained for 105 specimens. Twenty-four haplotypes were detected from six populations, only Kunes River population and Kashi River population shared haplotypes with each other. For all the populations examined, the haplotype diversity (h) was 0.904 8±0.012 6, nucleotide diversity (n) was 0.027 9±0.013 9, and the average number of pairwise nucleotide differences (k) was 15.878 3±7.139 1. The analysis of molecular variance (AMOVA) showed that 86.31% of the total genetic variation was apportioned among populations, and the variation within sampled populations was 13.69%. Genetic differences among sampled populations were highly significant. Fst statistical test indicated that all populations were significantly divergent from each other (P〈0.01). The largest Fst value was between Yurungkash River population and Muzat River population, while the smallest fst value was between Kunes River population and Kashi River population. NJ phylogenetic tree of D-loop haplotypes revealed two main clades. The neutrality test and mismatch distribution analysis suggested that the fish had went through a recent population expansion. The uplift of Tianshan Mountain and movement of Qinghai-Tibetan Plateau might contribute to the wide genetic divergence of D. maculates in northwest China. 展开更多
关键词 D. maculates Tarim River system Ili River system genetic divergence genetic structure
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Chloroplast genomic diversity in Bulbophyllum section Macrocaulia(Orchidaceae,Epidendroideae,Malaxideae):Insights into species divergence and adaptive evolution 被引量:3
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作者 Hanqing Tang Lu Tang +3 位作者 Shicheng Shao Yulan Peng Lu Li Yan Luo 《Plant Diversity》 SCIE CAS CSCD 2021年第5期350-361,共12页
Bulbophyllum is the largest genus in Orchidaceae with a pan tropical distribution.Due to highly significant diversifications,it is considered to be one of the most taxonomically and phylogenetically complex taxa.The d... Bulbophyllum is the largest genus in Orchidaceae with a pan tropical distribution.Due to highly significant diversifications,it is considered to be one of the most taxonomically and phylogenetically complex taxa.The diversification pattern and evolutionary adaptation of chloroplast genomes are poorly understood in this species-rich genus,and suitable molecular markers are necessary for species determination and phylogenetic analysis.A natural Asian section Macrocaulia was selected to estimate the interspecific divergence of chloroplast genomes in this study.Here,we sequenced the complete chloroplast genome of four Bulbophyllum species,including three species from section Macrocaulia.The four chloroplast genomes had a typical quadripartite structure with a genome size ranged from 156,182 to 158,524 bp.The chloroplast genomes included 113 unique genes encoding 79 proteins,30 tRNAs and 4 rRNAs.Comparison of the four chloroplast genomes showed that the three species from section Macrocaulia had similar structure and gene contents,and shared a number of indels,which mainly contribute to its monophyly.In addition,interspecific divergence level was also great.Several exclusive indels and polymorphism SSR loci might be used for taxonomical identification and determining interspecific polymorphisms.A total of 20 intergenic regions and three coding genes of the most variable hotspot regions were proposed as candidate effective molecular markers for future phylogenetic relationships at different taxonomical levels and species divergence in Bulbophyllum.All of chloroplast genes in four Bulbophyllum species were under purifying selection,while 13 sites within six genes exhibited sitespecific selection.A whole chloroplast genome phylogenetic analysis based on Maximum Likelihood,Bayesian and Parsimony methods all supported the monophyly of section Macrocaulia and the genus of Bulbophyllum.Our findings provide valuable molecular markers to use in accurately identifying species,clarifying taxonomy,and resolving the phylogeny and evolution of the genus Bulbophyllum.The molecular markers developed in this study will also contribute to further research of conservation of Bulbophyllum species. 展开更多
关键词 Chloroplast genome Sequence divergence DNA markers SSR BULBOPHYLLUM ORCHIDACEAE
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THE DIVERGENCE OF LAGRANGE INTERPOLATION IN EQUIDISTANT NODES 被引量:5
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作者 Lu Zhikang and Xia Mao (Hangzhou Teacher’s College, China)Department of Mathematics Hangzhou Teacher’s College Hangzhou,310012 P.R.China 《Analysis in Theory and Applications》 2003年第2期160-165,共6页
It is a classical result of Bernstein that the sequence of Lagrange interpolation polynomials to \x\ at e-qually spaced nodes in [-1.1] diverges everywhere. except at zero and the end-points. In this paper we show tha... It is a classical result of Bernstein that the sequence of Lagrange interpolation polynomials to \x\ at e-qually spaced nodes in [-1.1] diverges everywhere. except at zero and the end-points. In this paper we show that the sequence of Lagrange interpolation polynomials corresponding to the functions which possess better smoothness on equidistant nodes in [-1.1] still diverges every -where in the interval except at zero and the end-points. 展开更多
关键词 lagrange interpolation equidistant nodes divergence
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Mechanisms of species divergence through visual adaptation and sexual selection:Perspectives from a cichlid model system 被引量:3
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作者 Martine E.MAAN Ole SEEHAUSEN 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第3期285-299,共15页
The theory of ecological speciation suggests that assortative mating evolves most easily when mating preferences aredirectly linked to ecological traits that are subject to divergent selection. Sensory adaptation can ... The theory of ecological speciation suggests that assortative mating evolves most easily when mating preferences aredirectly linked to ecological traits that are subject to divergent selection. Sensory adaptation can play a major role in this process,because selective mating is often mediated by sexual signals: bright colours, complex song, pheromone blends and so on. Whendivergent sensory adaptation affects the perception of such signals, mating patterns may change as an immediate consequence.Alternatively, mating preferences can diverge as a result of indirect effects: assortative mating may be promoted by selectionagainst intermediate phenotypes that are maladapted to their (sensory) environment. For Lake Victoria cichlids, the visual environmentconstitutes an important selective force that is heterogeneous across geographical and water depth gradients. We investigatethe direct and indirect effects of this heterogeneity on the evolution of female preferences for alternative male nuptial colours(red and blue) in the genus Pundamilia. Here, we review the current evidence for divergent sensory drive in this system, extractgeneral principles, and discuss future perspectives [Current Zoology 56 (3): 285-299, 2010]. 展开更多
关键词 CICHLID Sexual selection Species divergence Visual adaptation
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Elevational divergence in the great tit complex revealed by major hemoglobin genes 被引量:3
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作者 Xiaojia ZHu Yuyan GUAN +3 位作者 Yanhua Qu Gabriel DAVID Gang SONG Fumin LEI 《Current Zoology》 SCIE CAS CSCD 2018年第4期455-464,共10页
Gene flow and demographic history can play important roles in the adaptive genetic differentiation of species, which is rarely understood in the high-altitude adaptive evolution of birds. To elucidate genetic divergen... Gene flow and demographic history can play important roles in the adaptive genetic differentiation of species, which is rarely understood in the high-altitude adaptive evolution of birds. To elucidate genetic divergence of populations in the great tit complex (Parus major, P. minor and P. cinereus) at different elevations, we compared the genetic structure and gene flow in hemoglobin genes with neutral loci. Our results revealed the elevationally divergent structure of αA-globin gene, distinctive from that of the/βA-globin gene and neutral loci. We further investigated gene flow patterns among the populations in the central-northern (〉 1,000 m a.s.l.), south-eastern (〈 1,000 m a.s.l.) regions and the Southwest Mountains (〉2,000 m a.s.l.) in China. The high-altitude (〉 1,000 m a.s.l.) diverged aA-globin genetic structure coincidαed with higher αA-globin gene flow between highland populations, in contrast to restricted neutral gene flow concordant with the phylogeny. The higher aA-globin gene flow suggests the possibility of adaptive evolution during population divergence, contrary to the lower aA-globin gene flow homogenized by neutral loci during population expantion. In concordance with patterns of historical gene flow, genotypic and allelic profiles provide distinctive patterns of fixation in different high-altitude populations. The fixation of alleles at contrasting elevations may primarily due to highland standing variants aA49Asn/72Asn/108Ala originating from the south-western population. Our findings demonstrate a pattern of genetic divergence with gene flow in major hemoglobin genes depending on population demographic history. 展开更多
关键词 elevational divergence gene flow genetic structure hemoglobin gene
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