The artificial immune system,an excellent prototype for developingMachine Learning,is inspired by the function of the powerful natural immune system.As one of the prevalent classifiers,the Dendritic Cell Algorithm(DCA...The artificial immune system,an excellent prototype for developingMachine Learning,is inspired by the function of the powerful natural immune system.As one of the prevalent classifiers,the Dendritic Cell Algorithm(DCA)has been widely used to solve binary problems in the real world.The classification of DCA depends on a data preprocessing procedure to generate input signals,where feature selection and signal categorization are themain work.However,the results of these studies also show that the signal generation of DCA is relatively weak,and all of them utilized a filter strategy to remove unimportant attributes.Ignoring filtered features and applying expertise may not produce an optimal classification result.To overcome these limitations,this study models feature selection and signal categorization into feature grouping problems.This study hybridizes Grouping Genetic Algorithm(GGA)with DCA to propose a novel DCA version,GGA-DCA,for accomplishing feature selection and signal categorization in a search process.The GGA-DCA aims to search for the optimal feature grouping scheme without expertise automatically.In this study,the data coding and operators of GGA are redefined for grouping tasks.The experimental results show that the proposed algorithm has significant advantages over the compared DCA expansion algorithms in terms of signal generation.展开更多
Information on genetic relationship is of great value to maize (Zea mays L.) breeding. Theobjectives of this study were: 1) to classify 22 quality protein maize (QPM) inbreds intodifferent groups by using simple seque...Information on genetic relationship is of great value to maize (Zea mays L.) breeding. Theobjectives of this study were: 1) to classify 22 quality protein maize (QPM) inbreds intodifferent groups by using simple sequence repeats (SSR) markers, which included exotictropical, subtropical and domestic temperate QPM and normal maize inbreds; 2) to examine theconsistency of grouping results obtained from SSR, specific combining ability (SCA) analysis,and genetic backgrounds of these inbreds. A set of 39 polymorphic SSR primers was selected from70 primer pairs, which detected 136 alleles among the 22 lines. The mean polymorphisminformation content was 0.55. Based on analysis of genetic similarities, five groups wereidentified including Luda Red Cob, Sipingtou, Reid, Lancaster and a miscellaneous group withseveral tropical inbreds which could not be classified into the above four groups. The resultsgenerally agreed with previous results based on analysis of yield combining ability andpedigree data.展开更多
It is significant to combine multiple tasks into an optimal work package in decision-making of aircraft maintenance to reduce cost,so a cost rate model of combinatorial maintenance is an urgent need.However,the optima...It is significant to combine multiple tasks into an optimal work package in decision-making of aircraft maintenance to reduce cost,so a cost rate model of combinatorial maintenance is an urgent need.However,the optimal combination under various constraints not only involves numerical calculations but also is an NP-hard combinatorial problem.To solve the problem,an adaptive genetic algorithm based on cluster search,which is divided into two phases,is put forward.In the first phase,according to the density,all individuals can be homogeneously scattered over the whole solution space through crossover and mutation and better individuals are collected as candidate cluster centres.In the second phase,the search is confined to the neighbourhood of some selected possible solutions to accurately solve with cluster radius decreasing slowly,meanwhile all clusters continuously move to better regions until all the peaks in the question space is searched.This algorithm can efficiently solve the combination problem.Taking the optimization on decision-making of aircraft maintenance by the algorithm for an example,maintenance which combines multiple parts or tasks can significantly enhance economic benefit when the halt cost is rather high.展开更多
[Objectives]The genetic diversity and population genetic structure of 107 inbred lines of maize in Yunnan were analyzed,in order to provide technical support for maize germplasm innovation,genetic improvement of germp...[Objectives]The genetic diversity and population genetic structure of 107 inbred lines of maize in Yunnan were analyzed,in order to provide technical support for maize germplasm innovation,genetic improvement of germplasm resources,variety management,and lay a solid foundation for exploring genes related to fine traits in the future.[Methods]The 107 maize inbred lines generalized in Yunnan were selected,and 45 backbone inbred lines commonly used in China were used as reference for heterotic group classification.On Axiom Maize 56K SNP Array platform,maize SNP chips(56K)were used to scan the whole maize genome,and the NJ-tree model of Treebest was used to construct a phylogenetic tree.Principal component analysis(PCA)was conducted by GCTA(genome-wide complex trait analysis)to reveal the genetic diversity and population genetic structure.[Results]In the 107 Yunnan local inbred lines,5533 uniformly distributed high-quality SNP marker sites were finally detected.Based on the analysis of these SNP marker sites,Nei s gene diversity index(H)of 107 maize germplasm genes was 0.2981-0.5000 with an average value being 0.4832,and polymorphism information content(PIC)values were 0.2536-0.3750 with an average value being 0.3662.The minimum allele frequency value was 0.5000-0.8178 with an average value being 0.5744.The analysis of population genetic structure showed that when K=6,the maximum value of△K was the maximum,which meant that the inbred lines used in this study could be divided into six groups.They were Tangsi Pingtou blood relationship group,PB blood relationship group,335 female blood relationship group,Zi 330 and the Lüda Honggu blood relationship group,unknown group 1 and unknown group 2.No inbred lines were divided into other heterotic groups.Among them,37 inbred lines from the 2 unknown groups could not be classified into the same group as the 10 known heterotic groups in China.The results of principal component analysis showed that the 107 maize inbred lines generalized in Yunnan could be clearly distinguished from the backbone maize inbred lines commonly used in China.Most of the maize inbred lines in Yunnan were concentrated near the reference backbone inbred lines.But some Yunnan inbred lines were far away from the reference inbred lines commonly used in China.[Conclusions]The maize germplasm resources in Yunnan area were rich in genetic diversity,including multiple heterotic groups,and there was a rich genetic basis of breeding parents.They could be clearly distinguished from the backbone inbred lines commonly used in China,and some of them had a long genetic distance from the backbone inbred lines.The resources which have good application potential can be used to create new heterotic groups.展开更多
The cultivation of the marine species of shrimp Litopenaeus vannamei has emerged as one of the segments that best develop in the Brazilian aquaculture, representing the agribusiness that grew the most in recent years....The cultivation of the marine species of shrimp Litopenaeus vannamei has emerged as one of the segments that best develop in the Brazilian aquaculture, representing the agribusiness that grew the most in recent years. Regarding the economic importance of the farming of this species in Brazil, further studies on genetic improvement were conducted. A F2 segregating population consisting of 192 samples for each G1 and G2 families, from crossing inbred lines was used for the studies performed in the present work. The genetic linkage analysis was based on polymorphic markers derived from nine AFLP (Amplified Fragment Length Polymorphism) primers. Fourteen genetic linkage groups including 103 segregating polymorphic markers were constructed covering350 cMfor G1 and four genetic linkage groups including 59 markers were constructed covering300 cMfor G2. Simple marker analyses were performed among individuals evaluated phenotypically, finding markers linked to genes that may be potentially important and useful to assess characteristics of economic importance for traits related to weight and the disease IMN (idiopathic muscle necrosis). The statistical model including markers explained major proportion of phenotypic characteristic weight in relation to disease incidence IMN.展开更多
The aim of the present study is to detect the potential of the base population from diallel crosses of eight introduced strains of the Pacific white shrimp(Litopenaeus vannamei) for improving the yield. Heterosis an...The aim of the present study is to detect the potential of the base population from diallel crosses of eight introduced strains of the Pacific white shrimp(Litopenaeus vannamei) for improving the yield. Heterosis and heritability were estimated for pond survival at commercial farm conditions for the base population that included 207 full-sib families from a nested mating design by artificial insemination. Among all the hybrids,the heterosis ranged from –11.37%(UA1×UA2) to 20.53%(UA3×SIN) with an average of 0.953%. The results showed that more than half of the hybrids(51.85%) have negative heterosis for survival rate, but most of the hybrids with positive heterosis have high estimates. The high proportion of negative heterosis for survival rate reminders us that the survival trait also should be considered in the crossbreeding program to avoid yield decrease. However, high positive heterosis manifested in most of the hybrids for survival indicates the usefulness of these hybrids for improving the survival to obtain higher yield by crossbreeding in this breeding program. The heritability estimate for pond survival was 0.092±0.043 when genetic groups were included in the pedigree, and it was significantly different from zero(P〈0.05). The results from this study also indicated that significant improvement for survival is possible through selection in L. vannamei.展开更多
The paper reported the phenotype and allele frequency distribution of ABO and Rh(D) blood groups among Brahmin,an endogamous population from Visakhapatnam district,Andhra Pradesh,India.Blood samples of 100 unrelated B...The paper reported the phenotype and allele frequency distribution of ABO and Rh(D) blood groups among Brahmin,an endogamous population from Visakhapatnam district,Andhra Pradesh,India.Blood samples of 100 unrelated Brahmin individuals were screened for ABO and Rh(D) blood groups.The order of occurrence of ABO phenotypes was O>A>B.The corresponding allele frequencies were 0.530,0.315,and 0.155,respectively.The allele frequency of D (0.990) was more than d (0.010).The results were compared with the other caste population to understand the population variations.展开更多
The whitefly Bemisia tabaci has a global distribution and extensive genetic diversity. Recent phylogenetic analyses as well as crossing experiments suggest that B. tabaci is a complex composed of 〉 20 cryptic species...The whitefly Bemisia tabaci has a global distribution and extensive genetic diversity. Recent phylogenetic analyses as well as crossing experiments suggest that B. tabaci is a complex composed of 〉 20 cryptic species, but more crossing studies are required to examine the reproductive compatibility among the putative species and thus further clarify the systematics of this species complex. We conducted crossing experiments and behavioral observations to investigate the reproductive compatibility between the Mediterranean, Asia II 3, and Asia II 1 putative species ofB. tabaci collected from Zhejiang, China. Female progeny were never produced in inter-species crosses, demonstrating a lack of egg fertilization; while 55%-75% females were produced in all the intra-species treatments. Continuous behavioral observations showed that frequent courtship events occurred in both intra-species treatments and inter-putative species crosses. However, copulation events occurred only in the three intra-species treatments with one exception: that one copulation event occurred between Asia II 3 and Mediterranean in the crosses where two cohorts of females and males of different putative species were enclosed together in a small arena but were not allowed access to their intra-specific mates for a long period of time. These data demonstrated complete reproductive isolation between the Mediterranean, Asia II 3, and Asia II 1 putative species, and further showed that the isolation is due to lack of copulation. Demonstration of reproductive isolation between the Mediterranean and two indigenous putative species from China provides further evidence for the existence of cryptic species within the B. tabaci complex.展开更多
基金NSFC http://www.nsfc.gov.cn/for the support through Grants No.61877045Fundamental Research Project of Shenzhen Science and Technology Program for the support through Grants No.JCYJ2016042815-3956266.
文摘The artificial immune system,an excellent prototype for developingMachine Learning,is inspired by the function of the powerful natural immune system.As one of the prevalent classifiers,the Dendritic Cell Algorithm(DCA)has been widely used to solve binary problems in the real world.The classification of DCA depends on a data preprocessing procedure to generate input signals,where feature selection and signal categorization are themain work.However,the results of these studies also show that the signal generation of DCA is relatively weak,and all of them utilized a filter strategy to remove unimportant attributes.Ignoring filtered features and applying expertise may not produce an optimal classification result.To overcome these limitations,this study models feature selection and signal categorization into feature grouping problems.This study hybridizes Grouping Genetic Algorithm(GGA)with DCA to propose a novel DCA version,GGA-DCA,for accomplishing feature selection and signal categorization in a search process.The GGA-DCA aims to search for the optimal feature grouping scheme without expertise automatically.In this study,the data coding and operators of GGA are redefined for grouping tasks.The experimental results show that the proposed algorithm has significant advantages over the compared DCA expansion algorithms in terms of signal generation.
文摘Information on genetic relationship is of great value to maize (Zea mays L.) breeding. Theobjectives of this study were: 1) to classify 22 quality protein maize (QPM) inbreds intodifferent groups by using simple sequence repeats (SSR) markers, which included exotictropical, subtropical and domestic temperate QPM and normal maize inbreds; 2) to examine theconsistency of grouping results obtained from SSR, specific combining ability (SCA) analysis,and genetic backgrounds of these inbreds. A set of 39 polymorphic SSR primers was selected from70 primer pairs, which detected 136 alleles among the 22 lines. The mean polymorphisminformation content was 0.55. Based on analysis of genetic similarities, five groups wereidentified including Luda Red Cob, Sipingtou, Reid, Lancaster and a miscellaneous group withseveral tropical inbreds which could not be classified into the above four groups. The resultsgenerally agreed with previous results based on analysis of yield combining ability andpedigree data.
基金supported by the National Natural Science Foundation of China(6107901361079014+4 种基金61403198)the National Natural Science Funds and Civil Aviaiton Mutual Funds(U1533128U1233114)the Programs of Natural Science Foundation of China and China Civil Aviation Joint Fund(60939003)the Natural Science Foundation of Jiangsu Province in China(BK2011737)
文摘It is significant to combine multiple tasks into an optimal work package in decision-making of aircraft maintenance to reduce cost,so a cost rate model of combinatorial maintenance is an urgent need.However,the optimal combination under various constraints not only involves numerical calculations but also is an NP-hard combinatorial problem.To solve the problem,an adaptive genetic algorithm based on cluster search,which is divided into two phases,is put forward.In the first phase,according to the density,all individuals can be homogeneously scattered over the whole solution space through crossover and mutation and better individuals are collected as candidate cluster centres.In the second phase,the search is confined to the neighbourhood of some selected possible solutions to accurately solve with cluster radius decreasing slowly,meanwhile all clusters continuously move to better regions until all the peaks in the question space is searched.This algorithm can efficiently solve the combination problem.Taking the optimization on decision-making of aircraft maintenance by the algorithm for an example,maintenance which combines multiple parts or tasks can significantly enhance economic benefit when the halt cost is rather high.
基金Study on Maize Variety Management Based on DUS Test and SNP Molecular Fingerprint.
文摘[Objectives]The genetic diversity and population genetic structure of 107 inbred lines of maize in Yunnan were analyzed,in order to provide technical support for maize germplasm innovation,genetic improvement of germplasm resources,variety management,and lay a solid foundation for exploring genes related to fine traits in the future.[Methods]The 107 maize inbred lines generalized in Yunnan were selected,and 45 backbone inbred lines commonly used in China were used as reference for heterotic group classification.On Axiom Maize 56K SNP Array platform,maize SNP chips(56K)were used to scan the whole maize genome,and the NJ-tree model of Treebest was used to construct a phylogenetic tree.Principal component analysis(PCA)was conducted by GCTA(genome-wide complex trait analysis)to reveal the genetic diversity and population genetic structure.[Results]In the 107 Yunnan local inbred lines,5533 uniformly distributed high-quality SNP marker sites were finally detected.Based on the analysis of these SNP marker sites,Nei s gene diversity index(H)of 107 maize germplasm genes was 0.2981-0.5000 with an average value being 0.4832,and polymorphism information content(PIC)values were 0.2536-0.3750 with an average value being 0.3662.The minimum allele frequency value was 0.5000-0.8178 with an average value being 0.5744.The analysis of population genetic structure showed that when K=6,the maximum value of△K was the maximum,which meant that the inbred lines used in this study could be divided into six groups.They were Tangsi Pingtou blood relationship group,PB blood relationship group,335 female blood relationship group,Zi 330 and the Lüda Honggu blood relationship group,unknown group 1 and unknown group 2.No inbred lines were divided into other heterotic groups.Among them,37 inbred lines from the 2 unknown groups could not be classified into the same group as the 10 known heterotic groups in China.The results of principal component analysis showed that the 107 maize inbred lines generalized in Yunnan could be clearly distinguished from the backbone maize inbred lines commonly used in China.Most of the maize inbred lines in Yunnan were concentrated near the reference backbone inbred lines.But some Yunnan inbred lines were far away from the reference inbred lines commonly used in China.[Conclusions]The maize germplasm resources in Yunnan area were rich in genetic diversity,including multiple heterotic groups,and there was a rich genetic basis of breeding parents.They could be clearly distinguished from the backbone inbred lines commonly used in China,and some of them had a long genetic distance from the backbone inbred lines.The resources which have good application potential can be used to create new heterotic groups.
基金Fundacao de Amparo a Pesquisa do Estado de Sao Paulo(Fapesp)and Conselho Nacional de Desenvolvimento Cientifico e Tecnologico(CNPq)for financial support
文摘The cultivation of the marine species of shrimp Litopenaeus vannamei has emerged as one of the segments that best develop in the Brazilian aquaculture, representing the agribusiness that grew the most in recent years. Regarding the economic importance of the farming of this species in Brazil, further studies on genetic improvement were conducted. A F2 segregating population consisting of 192 samples for each G1 and G2 families, from crossing inbred lines was used for the studies performed in the present work. The genetic linkage analysis was based on polymorphic markers derived from nine AFLP (Amplified Fragment Length Polymorphism) primers. Fourteen genetic linkage groups including 103 segregating polymorphic markers were constructed covering350 cMfor G1 and four genetic linkage groups including 59 markers were constructed covering300 cMfor G2. Simple marker analyses were performed among individuals evaluated phenotypically, finding markers linked to genes that may be potentially important and useful to assess characteristics of economic importance for traits related to weight and the disease IMN (idiopathic muscle necrosis). The statistical model including markers explained major proportion of phenotypic characteristic weight in relation to disease incidence IMN.
基金The National Natural Science Foundation of China under contract No.31302179the Taishan Scholar Program for Seed Industry+4 种基金the Introduction of International Advanced Agricultural Science and Technology Plan under contract No.2016-X39the Special Fund for Basic Scientific Research Business of Central Public Research Institutes under contract No.2015B04XK01China Postdoctoral Science Foundation under contract No.2015M572095Qingdao Scientific Research Foundation under contract No.14-2-4-52-jch5Jiangsu Province Science and Technology Support Project under contract No.BE2014414
文摘The aim of the present study is to detect the potential of the base population from diallel crosses of eight introduced strains of the Pacific white shrimp(Litopenaeus vannamei) for improving the yield. Heterosis and heritability were estimated for pond survival at commercial farm conditions for the base population that included 207 full-sib families from a nested mating design by artificial insemination. Among all the hybrids,the heterosis ranged from –11.37%(UA1×UA2) to 20.53%(UA3×SIN) with an average of 0.953%. The results showed that more than half of the hybrids(51.85%) have negative heterosis for survival rate, but most of the hybrids with positive heterosis have high estimates. The high proportion of negative heterosis for survival rate reminders us that the survival trait also should be considered in the crossbreeding program to avoid yield decrease. However, high positive heterosis manifested in most of the hybrids for survival indicates the usefulness of these hybrids for improving the survival to obtain higher yield by crossbreeding in this breeding program. The heritability estimate for pond survival was 0.092±0.043 when genetic groups were included in the pedigree, and it was significantly different from zero(P〈0.05). The results from this study also indicated that significant improvement for survival is possible through selection in L. vannamei.
文摘The paper reported the phenotype and allele frequency distribution of ABO and Rh(D) blood groups among Brahmin,an endogamous population from Visakhapatnam district,Andhra Pradesh,India.Blood samples of 100 unrelated Brahmin individuals were screened for ABO and Rh(D) blood groups.The order of occurrence of ABO phenotypes was O>A>B.The corresponding allele frequencies were 0.530,0.315,and 0.155,respectively.The allele frequency of D (0.990) was more than d (0.010).The results were compared with the other caste population to understand the population variations.
基金Acknowledgments Financial support for this study was provided by the National Basic Research Programme of China (2009CB 119203) and the National Natural Science Foundation of China (30870372).
文摘The whitefly Bemisia tabaci has a global distribution and extensive genetic diversity. Recent phylogenetic analyses as well as crossing experiments suggest that B. tabaci is a complex composed of 〉 20 cryptic species, but more crossing studies are required to examine the reproductive compatibility among the putative species and thus further clarify the systematics of this species complex. We conducted crossing experiments and behavioral observations to investigate the reproductive compatibility between the Mediterranean, Asia II 3, and Asia II 1 putative species ofB. tabaci collected from Zhejiang, China. Female progeny were never produced in inter-species crosses, demonstrating a lack of egg fertilization; while 55%-75% females were produced in all the intra-species treatments. Continuous behavioral observations showed that frequent courtship events occurred in both intra-species treatments and inter-putative species crosses. However, copulation events occurred only in the three intra-species treatments with one exception: that one copulation event occurred between Asia II 3 and Mediterranean in the crosses where two cohorts of females and males of different putative species were enclosed together in a small arena but were not allowed access to their intra-specific mates for a long period of time. These data demonstrated complete reproductive isolation between the Mediterranean, Asia II 3, and Asia II 1 putative species, and further showed that the isolation is due to lack of copulation. Demonstration of reproductive isolation between the Mediterranean and two indigenous putative species from China provides further evidence for the existence of cryptic species within the B. tabaci complex.