Osmanthus fragrans is a well-known ornamental plant that has been domesticated in China for 2500 years.More than 160 cultivars have been found during this long period of domestication,and they have subsequently been d...Osmanthus fragrans is a well-known ornamental plant that has been domesticated in China for 2500 years.More than 160 cultivars have been found during this long period of domestication,and they have subsequently been divided into four cultivar groups,including the Yingui,Jingui,Dangui,and Sijigui groups.These groups provide a set of materials to study genetic evolution and variability.Here,we constructed a reference genome of O.fragrans‘Liuyejingui’in the Jingui group and investigated its floral color traits and domestication history by resequencing a total of 122 samples,including 119 O.fragrans accessions and three other Osmanthus species,at an average sequencing depth of 15×.The population structure analysis showed that these 119 accessions formed an apparent regional cluster.The results of linkage disequilibrium(LD)decay analysis suggested that varieties with orange/red flower color in the Dangui group had undergone more artificial directional selection;these varieties had the highest LD values among the four groups,followed by the Sijigui,Jingui,and Yingui groups.Through a genome-wide association study,we further identified significant quantitative trait loci and genomic regions containing several genes,such as ethylene-responsive transcription factor 2 and Arabidopsis pseudoresponse regulator 2,that are positively associated with petal color.Moreover,we found a frameshift mutation with a 34-bp deletion in the first coding region of the carotenoid cleavage dioxygenase 4 gene.This frameshift mutation existed in at least one site on both alleles in all varieties of the Dangui group.The results from this study shed light on the genetic basis of domestication in woody plants,such as O.fragrans.展开更多
5,6-Dihydrothieno[3＇,2＇：4,5]thieno[2,3-d]pyrimidin-4（3H）-ones 6 were synthesized in yields of 71-87% by a consecutive method, which includes aza-Wittig reaction of iminophosphorane 3 with aromatic isocynate to gi...5,6-Dihydrothieno[3＇,2＇：4,5]thieno[2,3-d]pyrimidin-4（3H）-ones 6 were synthesized in yields of 71-87% by a consecutive method, which includes aza-Wittig reaction of iminophosphorane 3 with aromatic isocynate to give carbodiimide 4 and subsequent reaction of 4 with various amines, phenols or alcohols in the presence of catalytic amount of sodium ethoxide or solid potassium carbonate. 2009 Ming Wu Ding. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
As a means of transportation to reduce traffic congestion, the metro has drawn increasing attention. In order to effectively enhance the beauty of the city's human landscape, authors of this paper, based on the pu...As a means of transportation to reduce traffic congestion, the metro has drawn increasing attention. In order to effectively enhance the beauty of the city's human landscape, authors of this paper, based on the public art dimension of metro, explore the artistic expression, problems, and countermeasures related to the enhancement of the beauty of human landscape, and solutions to the common failing of metropolises in the evolution of urban civilization, so as to optimize and spread the urban culture. It is hoped that this paper can cover the shortage of relevant domestic and international studies and provide a theoretical reference for the majority of man-made landscape researchers.展开更多
Based on the tilt observation of an ancient tower, the method of calculating the tilt direction and tilt by using the strict adjustment method was introduced to calculate the coordinates of the center of gravity of a ...Based on the tilt observation of an ancient tower, the method of calculating the tilt direction and tilt by using the strict adjustment method was introduced to calculate the coordinates of the center of gravity of a structure, so as to provide a reference for the tilt observation of other circular structures or high-rise buildings.展开更多
In this paper, a predator-prey ecological economic system with nonlinear harvesting rate is formulated and studied. This system is described by a differential-algebraic equation. By employing local parameterization me...In this paper, a predator-prey ecological economic system with nonlinear harvesting rate is formulated and studied. This system is described by a differential-algebraic equation. By employing local parameterization method, an equivalent differen- tial system with parameter is obtained. Then by normal form the-ory and bifurcation theory, the complex dynamics of the system are investigated, including the local stability of equilibrium point and Hopf bifurcation. Finally, MATLAB simulation illustrates the effectiveness of our results.展开更多
基金supported by research grants provided by the National Natural Science Foundation of China(31600569 and 31700617)the Natural Science Foundation of Hubei Province(2017CFB235)+1 种基金the Nuclear Technology Innovation team project of Hubei University of Science and Technology(H2019002)the Science and Technology Project of Xianning(2020NYYF02)。
文摘Osmanthus fragrans is a well-known ornamental plant that has been domesticated in China for 2500 years.More than 160 cultivars have been found during this long period of domestication,and they have subsequently been divided into four cultivar groups,including the Yingui,Jingui,Dangui,and Sijigui groups.These groups provide a set of materials to study genetic evolution and variability.Here,we constructed a reference genome of O.fragrans‘Liuyejingui’in the Jingui group and investigated its floral color traits and domestication history by resequencing a total of 122 samples,including 119 O.fragrans accessions and three other Osmanthus species,at an average sequencing depth of 15×.The population structure analysis showed that these 119 accessions formed an apparent regional cluster.The results of linkage disequilibrium(LD)decay analysis suggested that varieties with orange/red flower color in the Dangui group had undergone more artificial directional selection;these varieties had the highest LD values among the four groups,followed by the Sijigui,Jingui,and Yingui groups.Through a genome-wide association study,we further identified significant quantitative trait loci and genomic regions containing several genes,such as ethylene-responsive transcription factor 2 and Arabidopsis pseudoresponse regulator 2,that are positively associated with petal color.Moreover,we found a frameshift mutation with a 34-bp deletion in the first coding region of the carotenoid cleavage dioxygenase 4 gene.This frameshift mutation existed in at least one site on both alleles in all varieties of the Dangui group.The results from this study shed light on the genetic basis of domestication in woody plants,such as O.fragrans.
基金support of this work by the National Natural Science Foundation of China(No.20772041)Key Project of Science and Technology of Ministry of Education of China(No.107082)
文摘5,6-Dihydrothieno[3＇,2＇：4,5]thieno[2,3-d]pyrimidin-4（3H）-ones 6 were synthesized in yields of 71-87% by a consecutive method, which includes aza-Wittig reaction of iminophosphorane 3 with aromatic isocynate to give carbodiimide 4 and subsequent reaction of 4 with various amines, phenols or alcohols in the presence of catalytic amount of sodium ethoxide or solid potassium carbonate. 2009 Ming Wu Ding. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
基金Sponsored by Shaanxi Provincial Training Programs of Innovation and Entrepreneurship for Undergraduates(201710712050)
文摘As a means of transportation to reduce traffic congestion, the metro has drawn increasing attention. In order to effectively enhance the beauty of the city's human landscape, authors of this paper, based on the public art dimension of metro, explore the artistic expression, problems, and countermeasures related to the enhancement of the beauty of human landscape, and solutions to the common failing of metropolises in the evolution of urban civilization, so as to optimize and spread the urban culture. It is hoped that this paper can cover the shortage of relevant domestic and international studies and provide a theoretical reference for the majority of man-made landscape researchers.
文摘Based on the tilt observation of an ancient tower, the method of calculating the tilt direction and tilt by using the strict adjustment method was introduced to calculate the coordinates of the center of gravity of a structure, so as to provide a reference for the tilt observation of other circular structures or high-rise buildings.
基金Supported by the National Natural Science Foundation of China(61304057)the Research Program of Hubei Normal University(ky201302)the Young and Middle-Aged Elitists’Scientific and Technological Innovation Team Project of the Institutions of Higher Education in Hubei Province(T2014212)
文摘In this paper, a predator-prey ecological economic system with nonlinear harvesting rate is formulated and studied. This system is described by a differential-algebraic equation. By employing local parameterization method, an equivalent differen- tial system with parameter is obtained. Then by normal form the-ory and bifurcation theory, the complex dynamics of the system are investigated, including the local stability of equilibrium point and Hopf bifurcation. Finally, MATLAB simulation illustrates the effectiveness of our results.
