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Tectonic features,genetic mechanisms and basin evolution of the eastern Doseo Basin,Chad 被引量:1
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作者 GAO Huahua DU Yebo +7 位作者 WANG Lin GAO Simin HU Jie BAI Jianfeng MA Hong WANG Yuhua ZHANG Xinshun LIU Hao 《Petroleum Exploration and Development》 SCIE 2023年第5期1151-1166,共16页
The features of the unconformity,fault and tectonic inversion in the eastern Doseo Basin,Chad,were analyzed,and the genetic mechanisms and basin evolution were discussed using seismic and drilling data.The following r... The features of the unconformity,fault and tectonic inversion in the eastern Doseo Basin,Chad,were analyzed,and the genetic mechanisms and basin evolution were discussed using seismic and drilling data.The following results are obtained.First,four stratigraphic unconformities,i.e.basement(Tg),Mangara Group(T10),lower Upper Cretaceous(T5)and Cretaceous(T4),four faulting stages,i.e.Barremian extensional faults,Aptian–Coniacian strike-slip faults,Campanian strike-slip faults,and Eocene strike-slip faults,and two tectonic inversions,i.e.Santonian and end of Cretaceous,were developed in the Doseo Basin.Second,the Doseo Basin was an early failed intracontinental passive rift basin transformed by the strike-slip movement and tectonic inversion.The initial rifting between the African and South American plates induced the nearly N-S stretching of the Doseo Basin,giving rise to the formation of the embryonic Doseo rift basin.The nearly E-W strike-slip movement of Borogop(F1)in the western section of the Central African Shear Zone resulted in the gradual cease of the near north-south rifting and long-term strike-slip transformation,forming a dextral transtension fault system with inherited activity but gradually weakened in intensity(interrupted by two tectonic inversions).This fault system was composed of the main shear(F1),R-type shear(F2-F3)and P-type shear(F4-F5)faults,with the strike-slip associated faults as branches.The strike-slip movements of F1 in Cretaceous and Eocene were controlled by the dextral shear opening of the equatorial south Atlantic and rapid expanding of the Indian Ocean,respectively.The combined function of the strike-slip movement of F1 and the convergence between Africa and Eurasia made the Doseo Basin underwent the Santonian dextral transpressional inversion characterized by intensive folding deformation leading to the echelon NE-SW and NNE-SSW nose-shaped uplifts and unconformity(T5)on high parts of the uplifts.The convergence between Africa and Eurasia caused the intensive tectonic inversion of Doseo Basin at the end of Cretaceous manifesting as intensive uplift,denudation and folding deformation,forming the regional unconformity(T4)and superposing a nearly E-W structural configuration on the Santonian structures.Third,the Doseo Basin experienced four evolutional stages with the features of short rifting and long depression,i.e.Barremian rifting,Aptian rifting–depression transition,Albian–Late Cretaceous depression,and Cenozoic extinction,under the control of the tectonic movements between Africa and its peripheral plates. 展开更多
关键词 Doseo Basin CRETACEOUS UNCONFORMITY strike-slip fault tectonic inversion genetic mechanism basin evolution
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Paleoenvironmental Evolution and Organic Matter Enrichment Genesis of the Late Turonian Black Shale in the Southern Songliao Basin,NE China
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作者 BAI Jing XU Xingyou +2 位作者 LIU Weibin ZHAO Wenzhi JIANG Hang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1338-1358,共21页
The Upper Cretaceous Qingshankou Formation black shales,deposited in the late Turonian(LTB shales),are the main source rocks of the Songliao Basin.The origins of organic matter enrichment of the shales is a contentiou... The Upper Cretaceous Qingshankou Formation black shales,deposited in the late Turonian(LTB shales),are the main source rocks of the Songliao Basin.The origins of organic matter enrichment of the shales is a contentious subject fuelling many ongoing debates.This study investigates the genesis of the organic matter-rich shale by using molecular geochemistry.The LTB shales can be divided into three sections.The SectionⅠshales were deposited in saline,stratified and anoxic water conditions,which are related to seawater incursion events.At least three episodic and periodic seawater incursion events were recognized during SectionⅠshale deposition.The SectionⅡshales deposited in brackish to fresh and deep lake-level conditions with high primary productivity,which are related to lake-level transgression.The SectionⅢshales were deposited under fresh and slightly oxidized water conditions,which are related to lake-level regression.Two organic matter enrichment models for the LTB shales are identified,that is,the seawater incursion model and the maximum lake-level transgression sedimentation model,which act on different shale sections,both playing significant roles in the enrichment of organic matter. 展开更多
关键词 organic matter-rich shale paleoenvironmental evolution enrichment genetics late Turonian CRETACEOUS Songliao Basin
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Strengthened Dominance Relation NSGA-Ⅲ Algorithm Based on Differential Evolution to Solve Job Shop Scheduling Problem
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作者 Liang Zeng Junyang Shi +2 位作者 Yanyan Li Shanshan Wang Weigang Li 《Computers, Materials & Continua》 SCIE EI 2024年第1期375-392,共18页
The job shop scheduling problem is a classical combinatorial optimization challenge frequently encountered in manufacturing systems.It involves determining the optimal execution sequences for a set of jobs on various ... The job shop scheduling problem is a classical combinatorial optimization challenge frequently encountered in manufacturing systems.It involves determining the optimal execution sequences for a set of jobs on various machines to maximize production efficiency and meet multiple objectives.The Non-dominated Sorting Genetic Algorithm Ⅲ(NSGA-Ⅲ)is an effective approach for solving the multi-objective job shop scheduling problem.Nevertheless,it has some limitations in solving scheduling problems,including inadequate global search capability,susceptibility to premature convergence,and challenges in balancing convergence and diversity.To enhance its performance,this paper introduces a strengthened dominance relation NSGA-Ⅲ algorithm based on differential evolution(NSGA-Ⅲ-SD).By incorporating constrained differential evolution and simulated binary crossover genetic operators,this algorithm effectively improves NSGA-Ⅲ’s global search capability while mitigating pre-mature convergence issues.Furthermore,it introduces a reinforced dominance relation to address the trade-off between convergence and diversity in NSGA-Ⅲ.Additionally,effective encoding and decoding methods for discrete job shop scheduling are proposed,which can improve the overall performance of the algorithm without complex computation.To validate the algorithm’s effectiveness,NSGA-Ⅲ-SD is extensively compared with other advanced multi-objective optimization algorithms using 20 job shop scheduling test instances.The experimental results demonstrate that NSGA-Ⅲ-SD achieves better solution quality and diversity,proving its effectiveness in solving the multi-objective job shop scheduling problem. 展开更多
关键词 Multi-objective job shop scheduling non-dominated sorting genetic algorithm differential evolution simulated binary crossover
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Rapid Prototype Development Approach for Genetic Programming
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作者 Pei He Lei Zhang 《Journal of Computer and Communications》 2024年第2期67-79,共13页
Genetic Programming (GP) is an important approach to deal with complex problem analysis and modeling, and has been applied in a wide range of areas. The development of GP involves various aspects, including design of ... Genetic Programming (GP) is an important approach to deal with complex problem analysis and modeling, and has been applied in a wide range of areas. The development of GP involves various aspects, including design of genetic operators, evolutionary controls and implementations of heuristic strategy, evaluations and other mechanisms. When designing genetic operators, it is necessary to consider the possible limitations of encoding methods of individuals. And when selecting evolutionary control strategies, it is also necessary to balance search efficiency and diversity based on representation characteristics as well as the problem itself. More importantly, all of these matters, among others, have to be implemented through tedious coding work. Therefore, GP development is both complex and time-consuming. To overcome some of these difficulties that hinder the enhancement of GP development efficiency, we explore the feasibility of mutual assistance among GP variants, and then propose a rapid GP prototyping development method based on πGrammatical Evolution (πGE). It is demonstrated through regression analysis experiments that not only is this method beneficial for the GP developers to get rid of some tedious implementations, but also enables them to concentrate on the essence of the referred problem, such as individual representation, decoding means and evaluation. Additionally, it provides new insights into the roles of individual delineations in phenotypes and semantic research of individuals. 展开更多
关键词 genetic Programming Grammatical evolution Gene Expression Programming Regression Analysis Mathematical Modeling Rapid Prototype Development
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Genetic Variation of Mitochondrial D-loop Region and Evolution Analysis in Some Chinese Cattle Breeds 被引量:13
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作者 贾善刚 陈宏 +4 位作者 张桂香 王志刚 雷初朝 姚茹 韩旭 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第6期510-518,共9页
The complete mitochondrial D-loop region from 123 individuals in 12 Chinese cattle breeds and two individuals in Germany Yellow cattle breed was sequenced and analyzed. The results were shown as follows: 93 variation... The complete mitochondrial D-loop region from 123 individuals in 12 Chinese cattle breeds and two individuals in Germany Yellow cattle breed was sequenced and analyzed. The results were shown as follows: 93 variations and 57 haplotypes were detected, and the average number of nucleotide difference was 22.708, nucleotide diversity (π) was 0.0251 ± 0.00479, and haplotype diversity (Hd) was 0.888 ± 0.026, indicating very high genetic diversity in Chinese cattle breeds. In the Neighbor-Joining tree, 13 cattle breeds were divided into two main clades, Bos taurus and Bos indicus; new Clade Ill had only one sequence from Apeijiaza cattle breed in Tibet, which was similar to that of yak at a higher level than other cattle breeds, proving the introgression of genes from the yak. The proportions of Bos taurus and Bos indicus were 64.3 % and 35.7 % respectively in Xigaze Humped cattle breed, and 50.0% and 50.0% respectively in Apeijiaza cattle breed, which revealed that Tibet cattle included Bos indicus haplotypes. The importance of Yunnan cattle in the origin of Chinese cattle was also confirmed based on their abundant haplotypes. Then, a very special haplotype il discovered in 27 Chinese cattle breeds, including 11 breeds in this study and 16 breeds in the GenBank, played the role of a nucleus in Chinese zebu and was further discussed. At the same time, the construction of Chinese zebu core group based on haplotype il validated the distinct origin of Bos indicus in Tibet, which was different from that of the other cattle breeds with zebu haplotypes in China. 展开更多
关键词 ORIGIN evolution CATTLE mitochondrial D-loop genetic diversity
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Analysis on Genetic Diversity and Isolation Mechanism by Distance of Different Ecological Type Sheep Breeds in Mon-golia Sheep Group 被引量:1
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作者 孙伟 常洪 +4 位作者 冀德君 廖信军 杜垒 鲁生霞 角田健司 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第11期1001-1009,共9页
In the present study with Tan sheep, small-tailed Han sheep, Hu sheep, Tong sheep, and Wadi sheep, we detected the distribution of gene frequency of several microsatellite sites in different chromosomes, the result sh... In the present study with Tan sheep, small-tailed Han sheep, Hu sheep, Tong sheep, and Wadi sheep, we detected the distribution of gene frequency of several microsatellite sites in different chromosomes, the result showed that: 1) Hu sheep was in the status of Hardy-Weinberg extreme disequilibrium (P 〈 0.01), while populations including Tong sheep, small-tailed Han sheep, Tan sheep, and Wadi sheep were in Hardy-Weinberg equilibrium (P 〉 0.05). 2) Variance analysis of the heterozygosity and poly- morphic information content at rnicrosatellite makers showed that there were not significant differences among populations as to heterozygosity and PIC (P 〉 0.05), as to effective number of alleles there were not significant differences both among Tan sheep, Hu sheep, Tong sheep, and Wadi sheep, and between Wadi sheep and small-tailed sheep (P 〉 0.05), but between the former three populations and the latter two populations, there were significant differences (0.01〈 P 〈0.05). The variation levels of small-tailed Han sheep was the highest in the five populations based on microsatellite maker data, subsequently followed by Wadi sheep, Tong sheep, Tan sheep, and then Hu sheep. 3) The phylogenetic relationships of the five sheep populations in this study did not meet the mechanism of isolation by distance, and the genetic differentiation relationships among five sheep populations were not closely linearly correlative with their geography distribution. Our findings supported related records in literature: The five populations originated on different time stage from the primogenitor population and communicated genetically with each other thereafter in the process of natural and artificial selection and on different ecological environment. 展开更多
关键词 Mongolia sheep group different ecological type genetic diversity isolation by distance
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Relationship between SSR Genetic Distance and Heterosis in Hot Pepper
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作者 何建文 姜虹 +2 位作者 杨红 苏丹 刘永翔 《Agricultural Science & Technology》 CAS 2013年第9期1224-1227,1279,共5页
[Objective] This study aimed to predict the heterosis of hot pepper using SSR genetice distance. [Method] Twenty-five hybridized combinations between 10pepper parents were obtained through NCⅡ incomplete diallel cros... [Objective] This study aimed to predict the heterosis of hot pepper using SSR genetice distance. [Method] Twenty-five hybridized combinations between 10pepper parents were obtained through NCⅡ incomplete diallel cross to analyze the relationship between SSR genetic distance and heterosis. [Result] The genetic distance of the parents varied in a range from 0.13 to 0.33, and the average genetic distance was 0.25, indicating that the genetic difference was not obvious among the parents, namely, they shared a close genetic relationship. In addition, the SSR genetic distance was closely related to yield per plant and fruits per plant, but showed no obvious correlation with other traits. [Conclusion] This study proved that in a certain range the combinations between the parents with a distant genetic distance possessed stronger heterosis and a larger possibility to produce a high yield and vice versa. 展开更多
关键词 Hot pepper SSR genetic distance HETEROSIS
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Correlation Analysis of Genetic Distance and Heterosis of the Major Brassica napus L. Cultivars in Yunnan Province 被引量:1
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作者 刘岱 李淑娟 +5 位作者 张传利 朱海平 彭少丹 周筱妍 徐蕾 林良斌 《Agricultural Science & Technology》 CAS 2014年第11期1894-1898,共5页
[Objective] The correlation between genetic distance and heterosis of the major Brassica napus L. cultivars in Yunnan Province was analyzed. [Method] The genetic distances among the 8 major Brassica napus L. cultivars... [Objective] The correlation between genetic distance and heterosis of the major Brassica napus L. cultivars in Yunnan Province was analyzed. [Method] The genetic distances among the 8 major Brassica napus L. cultivars in Yunnan Province were investigated with the SSR molecular marker technique. Moreover, the correlation between genetic distance and field appearance of heterosis was ana-lyzed. [Result] There was a certain correlation between the genetic distance and heterosis of crossing parents (P〉0.05). [Conclusion] It is difficult to predict the het-erosis of Brassica napus L. cultivars and to screen parents by using the SSR molecular marker technique. 展开更多
关键词 Brassica napus L. genetic distance Heterosis Correlation
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Relationship Between Heterosis and Parental Genetic Distance Based on Molecular Markers for Functional Genes Related to Yield Traits in Rice 被引量:7
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作者 ZHANG Tao NI Xian-lin +7 位作者 JIANG Kai-feng DENG Hua-feng HE Qing YANG Qian-hua YANG Li WAN Xian-Qi CAO Ying-jiang ZHENG Jia-kui 《Rice science》 SCIE 2010年第4期288-295,共8页
The genetic distances among 18 cytoplasmic male sterile lines and 11 restorer lines were analyzed with molecular markers derived from yield-related functional genes. The correlation between parental genetic distance a... The genetic distances among 18 cytoplasmic male sterile lines and 11 restorer lines were analyzed with molecular markers derived from yield-related functional genes. The correlation between parental genetic distance and heterosis was investigated by analyzing the performance of 47 combinations. The results showed that the genetic distance was significantly correlated with yield heterosis (r=0.29^*), but not significantly correlated with heterosis for other traits, such as number of effective panicles per plant, seed setting rate, 1000-grain weight, number of grains per panicle and theoretical yield. However, the correlation coefficient was so small that the parental genetic distance could not to be used to predict heterosis. 展开更多
关键词 RICE yield related traits simple sequence repeats genetic distance HETEROSIS correlation
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Engineering graphitic carbon nitride with expanded interlayer distance for boosting photocatalytic hydrogen evolution 被引量:3
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作者 Qiushi Yang Shaonian Hu +3 位作者 Yaxuan Yao Xiangang Lin Haiwei Du Yupeng Yuan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期217-224,共8页
Regulating interlayer distance is a crucial factor in the development of two‐dimensional(2D)nanomaterials.A 2D metal‐free photocatalyst,such as graphitic carbon nitride(g‐C3N4),exhibits morphology‐and microstruct... Regulating interlayer distance is a crucial factor in the development of two‐dimensional(2D)nanomaterials.A 2D metal‐free photocatalyst,such as graphitic carbon nitride(g‐C3N4),exhibits morphology‐and microstructure‐dependent photocatalytic activity.Herein,we report a straightforward and facile route for the preparation of unique lamellar g‐C3N4,by co‐firing melamine and ammonium chloride via microwave‐assisted heating.Through the decomposition of NH4Cl,the evaporation of NH3 gas can effectively overcome van der Waals forces,expanding the interlayer distance of g‐C3N4,thereby creating a lamellar structure consisting of nanosheets.Compared with bulk g‐C3N4,the NH3‐derived lamellar g‐C3N4 exhibits a larger specific surface area and enhanced optical absorption capability,which increase photocatalytic hydrogen production because of the highly active structure,excellent utilization efficiency of photon energy,and low recombination efficiency of photogenerated charge carriers.This study provides a simple strategy for the regulation of the g‐C3N4 microstructure toward highly efficient photocatalytic applications. 展开更多
关键词 Graphitic carbon nitride Interlayer distance Microwave‐assisted heating Photocatalytic hydrogen evolution
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Relationship Between F_1,F_2 Hybrid Yield, Heterosis and Genetic Distance Measured by Molecular Markers and Parent Performance in Cotton 被引量:1
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作者 WU Yao-ting, ZHANG Tian-zhen, ZHU Xie-fei and WANG Guang-ming( National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University,Nanjing 210095 ,P.R. China Linqing Experimental Station , Cotton Research Center ofShandong Agricultural Academic Institute, Linqing 252600 ,P.R. China) 《Agricultural Sciences in China》 CAS CSCD 2002年第5期498-507,共10页
Genetic distance among 36 cotton cultivars measured by molecular markers of RAPDs, ISSRs, and SSRs was from 0.0701 to 0.4255 with the mean of 0.2844, and from 2.18 to 12.60 with the mean of 7.04 based on the genotype ... Genetic distance among 36 cotton cultivars measured by molecular markers of RAPDs, ISSRs, and SSRs was from 0.0701 to 0.4255 with the mean of 0.2844, and from 2.18 to 12.60 with the mean of 7.04 based on the genotype performance in two-year field experiments, which has a significant positive correlation (r = 0.3350). The correlative coefficients for boll number per plant, boll weight, yield per plant, lint percent and lint yield per plant were 0.8035,0.8877,0.7135,0.9640 and 0.8956 between F1 and F2 hybrid performance assessed by three-environment field experiments, respectively. The mean of F1 and F2 hybrid het-erosis of yield per plant and lint yield per plant were 13.62% , 16.31% , 7.90% and 9.02% , and the correlative coefficients between them were 0.3689 and 0.3787, respectively. The correlation between the genetic distance and heterosis was low, and influenced directly by the selected parents. 展开更多
关键词 COTTON Molecular markers PHENOTYPE genetic distance HETEROSIS
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An Analysis on the Relationship between Maize Heterosis and Genetic Distance 被引量:1
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作者 Yi ZHONG Renhai JIAO +3 位作者 Yanrong XU Xiuyun DAI Zongyun HOU Xing'er LIU 《Asian Agricultural Research》 2017年第3期77-79,共3页
13 normal maize inbred lines with quite different quantitative traits were used as experimental materials in this paper. The results showed that there was significantly positive correlation between genetic distance an... 13 normal maize inbred lines with quite different quantitative traits were used as experimental materials in this paper. The results showed that there was significantly positive correlation between genetic distance and plot yield,mid-parent heterosis,super heterosis,or SCA of yield. In a certain range,the longer the genetic distance between parental inbred lines,the stronger the heterosis. Therefore,in genetic practice,it was necessary to take the molecular genetic distance between inbred lines as an important reference. 展开更多
关键词 MAIZE HETEROSIS genetic distance YIELD
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Improved genetic distance-based spatial deployment can effectively minimize inbreeding in seed orchard 被引量:1
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作者 Boning Yang Haihong Sun +3 位作者 Jiandong Qi Shihui Niu Yousry AEl-Kassaby Wei Li 《Forest Ecosystems》 SCIE CSCD 2020年第1期117-124,126,125,127,共11页
Background:Inbreeding in seed orchards is expected to increase with the advancement of breeding cycles,which results in the delivery of crops with suboptimal genetic gain,reduced genetic diversity,and lower seed set.H... Background:Inbreeding in seed orchards is expected to increase with the advancement of breeding cycles,which results in the delivery of crops with suboptimal genetic gain,reduced genetic diversity,and lower seed set.Here,a genetic distance-dependent method for clonal spatial deployment in seed orchards was developed and demonstrated,which reduced the inbreeding levels.The method’s main evaluation parameter of inbreeding is the genetic distance among individuals and the deployment method used an improved adaptive parallel genetic algorithm(IAPGA)based on Python language.Using inbreeding-prone Chinese Mongolian pine breeding population material originating from a single natural population,the proposed method was compared to a traditional orchard design and a distance-based design;namely,complete randomized block(RCB)and optimum neighborhood(ONA)designs,respectively.Results:With the advancement of selective breeding cycles,group separation among orchard related individuals is expected to increase.Based on the genetic distance among individuals,the IAPGA design was superior in significantly reducing the inbreeding level as compared to the two existing designs,confirming its suitability to advanced-generation orchards where relatedness among parents is common.In the 1st,2nd,and mixed generations clonal deployment schemes,the IAPGA design produced lower inbreeding with 87.22%,81.49%,and 87.23%of RCB,and 92.78%,91.30%,and 91.67%of ONA designs,respectively.Conclusions:The IAPGA clonal deployment proposed in this study has the obvious advantage of controlling inbreeding,and it is expected to be used in clonal deployment in seed orchards on a large-scale.Further studies are needed to focus on the actual states of pollen dispersal and mating in seed orchards,and more assumptions should be taken into account for the optimized deployment method. 展开更多
关键词 SEED ORCHARD DEPLOYMENT INBREEDING genetic distance CLONE SSR
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A Genetic-Algorithm-Based Information Evolution Model for Social Networks
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作者 Yanan Wang Xiuzhen Chen +1 位作者 Jianhua Li Wanyu Huang 《China Communications》 SCIE CSCD 2016年第12期234-249,共16页
the existing information diffusion models focus on analyzing the spatial distribution of certain pieces of messages in social networks. However, these conventional models ignored another important characteristic of di... the existing information diffusion models focus on analyzing the spatial distribution of certain pieces of messages in social networks. However, these conventional models ignored another important characteristic of diffusion: gradually changing of message contents due to the ‘new' and ‘comment' mechanisms. A novel genetic-algorithm-based information evolution model is proposed to reproduce both the diffusion and development process of information in social networks. This model firstly proposes a five-tuple to represent three types of topics: independent, competitive and mutually exclusive. Furthermore, it adopts mutation operator and forms new crossover and mutation rules to simulate four typical interactions between individuals, which bring the advantage of reproducing the information evolution process in both popularity and content.A series of experiments tested on public datasets demonstrate that: 1) independent and competitive topics of information rarely affect each other while mutually exclusive topics significantly suppress the diffusion processes of each other; 2) lower mutation probability leads to decreasing of final information amount. The experimental results show that our evolution model is more reasonable and feasible in demonstrating the evolution of information in social networks. 展开更多
关键词 social network information evolution genetic algorithm MUTATION five-tuple PROLOG
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Genetic Evolution Analysis of Actinobacillus pleuropneumoniae
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作者 Yu LIANG Yanfei LIU Jiande YANG 《Agricultural Biotechnology》 CAS 2019年第2期113-115,118,共4页
In order to explore the genetic evolution of Actinobacillus pleuropneumoniae(App) in different countries and clarify the relationships among different App in each region, the 16 S rRNA gene of App in the NCBI nucleoti... In order to explore the genetic evolution of Actinobacillus pleuropneumoniae(App) in different countries and clarify the relationships among different App in each region, the 16 S rRNA gene of App in the NCBI nucleotide database was analyzed and compared by the bioinformatics method. The phylogenetic tree was constructed after tailoring alignment. The results showed that a stable genetic phenomenon was indicated in the evolutionary process of App. The isolates derived from China were clustered and showed a high degree of conservation. They had a certain genetic relationship with the British and American strains, but had far relationship with the strains from Japan which was a neighboring country of China. The isolates from different countries in the Eurasian continent shared high homology. The isolates of the two regions originated from common ancestors. 展开更多
关键词 ACTINOBACILLUS pleuropneumoniae genetic evolution PHYLOgenetic TREE HOMOLOGY comparison ORIGIN Relationship
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Genetic analysis of the maximum germination distance of Striga under Fusarium oxysporum f.sp.strigae biocontrol in sorghum
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作者 Emmanuel Mrema Hussein Shimelis +1 位作者 Mark Laing Learnmore Mwadzingeni 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第7期1585-1593,共9页
Maximum germination distance(MGD) is an important component of Striga resistance in sorghum. The objective of this study was to determine gene action influencing MGD of Striga hermonthica and Striga asiatica among s... Maximum germination distance(MGD) is an important component of Striga resistance in sorghum. The objective of this study was to determine gene action influencing MGD of Striga hermonthica and Striga asiatica among selected sorghum lines treated with a biocontrol agent, Fusarium oxysporum f. sp. strigae(FOS) for effective breeding with Striga resistance, and FOS compatibility. Twelve sorghum genotypes were selected based on their Striga resistance, FOS compatibility, and superior agronomic performance. Selected genotypes were crossed using a bi-parental mating design to generate six families for genetic analysis. Agar-gel assays were used to determine low haustorium initiation factor(LHF) using the 12 parental lines, their F_1 progenies, backcross derivatives, and F_2 segregants in two sets. One set had S. hermonthica seed and the other one had S. asiatica seed. Both were treated with and without FOS. Genotypes were evaluated using a split-plot design with three replications and MGD data were recorded followed by generation mean analysis. FOS reduced MGD by 1cm under both S. hermonthica and S. asiatica infestations. Additive, dominance, and epistatic gene actions were involved in the control of MGD of the two Striga species in the evaluated populations. On average, the relative contribution of additive, additive×additive and dominance×dominance genetic effects on the MGD of S. hermonthica and S. asiatica, with FOS, were 20, 33, and 36%; and 21, 32, and 35%, respectively. Breeding methods exploiting these genetic effects may provide enhanced response to selection for Striga resistance and FOS compatibility in integrated Striga management(ISM) programmes. 展开更多
关键词 Fusarium oxysporum f. sp. strigae genetic effect integrated Stnga management maximum germination distance sorghum
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Allopolyploidization increases genetic recombination in the ancestral diploid D genome during wheat evolution
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作者 Hongshen Wan Jun Li +6 位作者 Shengwei Ma Fan Yang Liang Chai Zehou Liu Qin Wang Zongjun Pu Wuyun Yang 《The Crop Journal》 SCIE CSCD 2022年第3期743-753,共11页
Genetic recombination produces new allelic combinations,thereby introducing variation for domestication.Allopolyploidization has increased the evolutionary potential of hexaploid common wheat by conferring the advanta... Genetic recombination produces new allelic combinations,thereby introducing variation for domestication.Allopolyploidization has increased the evolutionary potential of hexaploid common wheat by conferring the advantages of heterosis and gene redundancy,but whether a relationship exists between allopolyploidization and genetic recombination is currently unknown.To study the impact of allopolyploid ization on genetic recombination in the ancestral D genome of wheat,we generated new synthetic hexaploid wheats by crossing tetraploid Triticum turgidum with multiple diploid Aegilops tauschii accessions,with subsequent chromosome doubling,to simulate the evolutionary hexaploidization process.Using the DArT-Seq approach,we determined the genotypes of two new synthetic hexaploid wheats with their parents,F;plants in a diploid population(2 x,D_(1)D_(1)×D_(2)D_(2))and its new synthetic hexaploid wheatderived population(6 x,AABBD_(1)D_(1)×AABBD_(2)D_(2)).About 11%of detected SNP loci spanning the D genome of Ae.tauschii were eliminated after allohexaploidization,and the degree of segregation distortion was increased in their hexaploid offspring from the F_(1) generation.Based on codominant genotypes,the mean genetic interval length and recombination frequency between pairs of adjacent and linked SNPs on D genome of the hexaploid F;population were 2.3 fold greater than those in the diploid F_(2) population,and the recombination frequency of Ae.tauschii was increased by their hexaploidization with T.turgidum.In conclusion,allopolyploidization increases genetic recombination of the ancestral diploid D genome of wheat,and DNA elimination and increased segregation distortion also occur after allopolyploidization.Increased genetic recombination could have produced more new allelic combinations subject to natural or artificial selection,helping wheat to spread rapidly to become a major global crop and thereby accelerating the evolution of wheat via hexaploidization. 展开更多
关键词 Synthetic wheat Hexaploidization Diploid D genome genetic recombination Acceleration of evolution
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Analysis of Genetic Evolution of Escherichia fergusonii
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作者 Junhua LIU Yilian ZHOU +2 位作者 Yaoxin CUI Yanfei LIU Jiande YANG 《Agricultural Biotechnology》 CAS 2020年第5期54-57,共4页
[Objectives]This study was conducted to explore the genetic evolution of Escherichia fergusonii in different countries and regions,and to clarify the genetic relationship of E.fergusonii in different countries and reg... [Objectives]This study was conducted to explore the genetic evolution of Escherichia fergusonii in different countries and regions,and to clarify the genetic relationship of E.fergusonii in different countries and regions.[Methods]Bioinformatics method and bacterial 16 S rRNA sequencing technology were used to sort out and prune 16 S rRNA genes isolated in laboratory and searched in NCBI database to construct a molecular evolutionary tree for analysis and comparison.[Results]The direction of evolution of E.fergusonii has broken through regions,and there was cross evolution among continents.The origin of E.fergusonii was the Asian continent,and its adaptability to arid climate was not strong.[Conclusions]This study revealed the genetic evolution laws of E.fergusonii in the spread and mutation of livestock and poultry diseases,and provides a theoretical reference for the prevention and treatment of the disease. 展开更多
关键词 Escherichia fergusonii genetic evolution relationship evolutionary tree HOMOLOGY KINSHIP ORIGIN
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Use of Context Blocks in Genetic Programming for Evolution of Robot Morphology
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作者 Michal Gregor Juraj Spalek Jan Capak 《Journal of Energy and Power Engineering》 2013年第6期1132-1140,共9页
The paper explores applications of genetic programming to co-evolution of morphology and low-level control. In most reasonably difficult tasks, facilitation provided by modularity has proved to be vital for successful... The paper explores applications of genetic programming to co-evolution of morphology and low-level control. In most reasonably difficult tasks, facilitation provided by modularity has proved to be vital for successful application of genetic programming. However, the need for sharing data among nodes in the syntactic tree becomes especially acute when evolving modular programs. It has been shown before that it may be beneficial that modules themselves be node-attached. The paper presents extensions to standard genetic programming (the so-called contexts and context blocks) that allow for straight-forward storage, retrieval, transfer, and modification of data stored in the context of a syntactic tree, and shared by multiple nodes. Framework is thus provided for both: data sharing and node-attached modules. Finally, using context blocks, a genetic algorithm has been embedded within genetic programming to evolve values of constants. In genetic programming evolution of constants has been a long-standing problem. The paper shows how context blocks can be utilized to provide a more granular and flexible approach to their evolution. As shown in previous works, node-attached modules perform favorably when compared with existing approaches. Concerning evolution of context block constants, it is shown here that they too perform favorably when compared with ephemeral constants. 展开更多
关键词 genetic programming robot morphology evolution context blocks.
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Evolution Performance of Symbolic Radial Basis Function Neural Network by Using Evolutionary Algorithms
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作者 Shehab Abdulhabib Alzaeemi Kim Gaik Tay +2 位作者 Audrey Huong Saratha Sathasivam Majid Khan bin Majahar Ali 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期1163-1184,共22页
Radial Basis Function Neural Network(RBFNN)ensembles have long suffered from non-efficient training,where incorrect parameter settings can be computationally disastrous.This paper examines different evolutionary algor... Radial Basis Function Neural Network(RBFNN)ensembles have long suffered from non-efficient training,where incorrect parameter settings can be computationally disastrous.This paper examines different evolutionary algorithms for training the Symbolic Radial Basis Function Neural Network(SRBFNN)through the behavior’s integration of satisfiability programming.Inspired by evolutionary algorithms,which can iteratively find the nearoptimal solution,different Evolutionary Algorithms(EAs)were designed to optimize the producer output weight of the SRBFNN that corresponds to the embedded logic programming 2Satisfiability representation(SRBFNN-2SAT).The SRBFNN’s objective function that corresponds to Satisfiability logic programming can be minimized by different algorithms,including Genetic Algorithm(GA),Evolution Strategy Algorithm(ES),Differential Evolution Algorithm(DE),and Evolutionary Programming Algorithm(EP).Each of these methods is presented in the steps in the flowchart form which can be used for its straightforward implementation in any programming language.With the use of SRBFNN-2SAT,a training method based on these algorithms has been presented,then training has been compared among algorithms,which were applied in Microsoft Visual C++software using multiple metrics of performance,including Mean Absolute Relative Error(MARE),Root Mean Square Error(RMSE),Mean Absolute Percentage Error(MAPE),Mean Bias Error(MBE),Systematic Error(SD),Schwarz Bayesian Criterion(SBC),and Central Process Unit time(CPU time).Based on the results,the EP algorithm achieved a higher training rate and simple structure compared with the rest of the algorithms.It has been confirmed that the EP algorithm is quite effective in training and obtaining the best output weight,accompanied by the slightest iteration error,which minimizes the objective function of SRBFNN-2SAT. 展开更多
关键词 Satisfiability logic programming symbolic radial basis function neural network evolutionary programming algorithm genetic algorithm evolution strategy algorithm differential evolution algorithm
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