多室油菜具有多室多粒的特征,是提高油菜产量的一个有效途径。利用青海芥菜型多室油菜的BC4分离群体对油菜多室基因Bjln2进行初步定位,对分离群体的性状分离比进行卡方检测,检测结果符合1∶1,表明多室性状遗传稳定。利用扩增片段长度多...多室油菜具有多室多粒的特征,是提高油菜产量的一个有效途径。利用青海芥菜型多室油菜的BC4分离群体对油菜多室基因Bjln2进行初步定位,对分离群体的性状分离比进行卡方检测,检测结果符合1∶1,表明多室性状遗传稳定。利用扩增片段长度多态性(amplified fragment length polymorphism,AFLP)与分群分析法(bulk segregate analysis,BSA)相结合的方法共筛选获得3个与目标基因紧密连锁的标记。连锁遗传分析的结果表明,3个AFLP标记均位于基因Bjln2的同侧,其中SA03MC16距Bjln2基因最近,遗传距离约为13.1 c M;SA14MC13距Bjln2基因最远,遗传距离约为23.5 c M;图谱总长23.5 c M,标记间平均图距为7.8 c M。研究结果为多室基因的精细定位及图位克隆奠定了基础。展开更多
Aim To study the dIelectric breakdown phenomenon in the materials with quenched disorder. Methods Renormolization group methods were used. Results The percolation limit for breakdown pc , the breakdown field Ec～(Pc-...Aim To study the dIelectric breakdown phenomenon in the materials with quenched disorder. Methods Renormolization group methods were used. Results The percolation limit for breakdown pc , the breakdown field Ec～(Pc-p)v, and the fractal dimension of the structure of dielectric breakdown df were obtained. Conclusion The breakdown properties of the materials with quenched disorder are characterized by universal power laws, where the exponents are universal.展开更多
The gene Pi15 for resistance of rice to Magnaporthe grisea was previously identified as being linked to the gene Pii. However, there is a debate on the chromosomal position of the Pii gene, because it was originally m...The gene Pi15 for resistance of rice to Magnaporthe grisea was previously identified as being linked to the gene Pii. However, there is a debate on the chromosomal position of the Pii gene, because it was originally mapped on chromosome 6, but recent work showed it might be located on chromosome 9. To determine the chromosomal location of the Pi15 gene, a linkage analysis using molecular markers was performed in a F2 mapping population consisting of 15 resistant and 141 susceptible plants through bulked-segregant analysis (BSA) in combination with recessive-class analysis (RCA). Out of 20 microsatellite markers mapped on chromosomes 6 and 9 tested, only one marker, RM316 on chromosome 9, was found to have a linkage with the Pi15 gene with a recombination frequency of (19.1 ±3.7)%. To confirm this finding, four sequence-tagged site (STS) markers mapped on chromosome 9 were tested. The results suggested that marker G103 was linked to the Pi15 gene with a recombination frequency of (5.7±2.1)%. To find marker(s) more closely linked to the Pi15 gene, random amplified polymorphic DNA (RAPD) analysis was performed. Out of 1 000 primers tested, three RAPD markers, BAPi15486, BAPi15782 and BAPil5844 were found to tightly flank the Pi15 gene with recombination frequencies of 0.35%, 0.35% and 1.1%, respectively. These three RAPD markers should be viewed as the starting points for marker-aided gene pyramiding and cloning. A new gene cluster of rice blast resistance on chromosome 9 was also discussed.展开更多
[Objective] The large-scale single-column fattening pig house with fermen- tation bed could hold 1 500 heads of fattening pigs. Since the number of pigs in piggery is too large, the management is difficult. The behavi...[Objective] The large-scale single-column fattening pig house with fermen- tation bed could hold 1 500 heads of fattening pigs. Since the number of pigs in piggery is too large, the management is difficult. The behavior of feeding, drinking, movement, sleeping, fighting of pigs is difficult to handle. The pigs cannot be man- aged well, resulting in the enhanced weakness of piglets, enhanced illness of weak pigs and missing treatment of ill pigs. The management for the pig populations is not satisfactory, and thus, it is needed to improve timely. [Method] The barriers for the fattening pigs in the large-scale pig house with fermentation bed were designed. The single management for single fattening pig was proposed. The large-scale fat- tening pig house was divided into 8 regions. Among them, 4 regions were located in both sides of the fermentation bed. Their main function was to separate ill, weak, small and bad pigs. In addition, the main column was divided into 4 gradual barri- ers. They were used to separate different-size fattening pigs. In view of manage- ment, the different-type pigs were managed dividedly with the gradual barriers. The equally-sized pigs were concentrated into one column. The ill, weak, small and bad pigs were isolated into barriers. Thus, the dynamic management was adopted. Until the fattening pigs grew up to 75 kg and their health was stable, the barriers among the columns were canceled to mix the pigs again and guarantee the pigs more gymnastic space. [Result] This design would improve the disease resistance of ill pigs, health status of weak pigs and management level of pig populations. This study would also provide a basis for the healthy running of large-scale fattening pig house with fermentation bed. [Conclusion] The pig-raising model with fermentation bed would improve the environment of pig house and the welfare of pigs. In addi- tion, the performance of pigs and quality of pork were also improved. The fermen- tation bed had an obvious advantage in safety and economics, and it had a broad application prospect.展开更多
According to the survey of Guangdong mangrove resource in 2001 and authors field investigations in the past 5 years, the total mature mangrove land area of Guangdong Province was estimated at 9084 hm2, accounting for ...According to the survey of Guangdong mangrove resource in 2001 and authors field investigations in the past 5 years, the total mature mangrove land area of Guangdong Province was estimated at 9084 hm2, accounting for 41.4% of total mangrove land area of China. These mangrove forests totally consisted of 50 species belonging to 28 families, distributed at more than 100 locations along the coastlines of Guangdong and most of them present a high dense and dwarf appearance. The Ass. Avicennia marina is the most dominant mangrove association. The investigation results showed that the mangrove forests with coverage rates above 0.7 accounted for 68.0% of the total mangrove land area of the province and 77.8% of mangrove forests was less than 2 m in tree height. Since 1950, 54.6% of mangrove forests have disappeared due to paddy rice reclaim, aquaculture and city constructions. Derivational conservation efforts are still weakly empowered and should be strengthened intensively. The author suggested that mangrove laws and regulations should be enforced, mangrove scientific research should be strengthened; and mangrove conservation awareness of local community should be raised on conservation of mangroves.展开更多
A complete approximate symmetry classification of a class of perturbed nonlinear wave equations isperformed using the method originated from Fushchich and Shtelen.Moreover,large classes of approximate invariantsolutio...A complete approximate symmetry classification of a class of perturbed nonlinear wave equations isperformed using the method originated from Fushchich and Shtelen.Moreover,large classes of approximate invariantsolutions of the equations based on the Lie group method are constructed.展开更多
The train schedule usually includes train stop schedule,routing scheme and formation scheme.It is the basis of subway transportation.Combining the practical experience of transport organizations and the principle of t...The train schedule usually includes train stop schedule,routing scheme and formation scheme.It is the basis of subway transportation.Combining the practical experience of transport organizations and the principle of the best match between transport capacity and passenger flow demand,taking the minimum value of passenger travel costs and corporation operating costs as the goal,considering the constraints of the maximum rail capacity,the minimum departure frequency and the maximum available electric multiple unit,an optimization model for city subway Y-type operation mode is constructed to determine the operation section of mainline as well as branch line and the train frequency of the Y-type operation mode.The particle swarm optimization(PSO)algorithm based on classification learning is used to solve the model,and the effectiveness of the model and algorithm is verified by a practical case.The results show that the length of branch line in Y-type operation affects the cost of waiting time of passengers significantly.展开更多
Lie group method provides an efficient tool to solve nonlinear partial differential equations. This paper suggests Lie group method for fractional partial differential equations. A time-fractional Burgers equation is ...Lie group method provides an efficient tool to solve nonlinear partial differential equations. This paper suggests Lie group method for fractional partial differential equations. A time-fractional Burgers equation is used as an example to illustrate the effectiveness of the Lie group method and some classes of exact solutions are obtained.展开更多
文摘多室油菜具有多室多粒的特征,是提高油菜产量的一个有效途径。利用青海芥菜型多室油菜的BC4分离群体对油菜多室基因Bjln2进行初步定位,对分离群体的性状分离比进行卡方检测,检测结果符合1∶1,表明多室性状遗传稳定。利用扩增片段长度多态性(amplified fragment length polymorphism,AFLP)与分群分析法(bulk segregate analysis,BSA)相结合的方法共筛选获得3个与目标基因紧密连锁的标记。连锁遗传分析的结果表明,3个AFLP标记均位于基因Bjln2的同侧,其中SA03MC16距Bjln2基因最近,遗传距离约为13.1 c M;SA14MC13距Bjln2基因最远,遗传距离约为23.5 c M;图谱总长23.5 c M,标记间平均图距为7.8 c M。研究结果为多室基因的精细定位及图位克隆奠定了基础。
文摘Aim To study the dIelectric breakdown phenomenon in the materials with quenched disorder. Methods Renormolization group methods were used. Results The percolation limit for breakdown pc , the breakdown field Ec～(Pc-p)v, and the fractal dimension of the structure of dielectric breakdown df were obtained. Conclusion The breakdown properties of the materials with quenched disorder are characterized by universal power laws, where the exponents are universal.
文摘The gene Pi15 for resistance of rice to Magnaporthe grisea was previously identified as being linked to the gene Pii. However, there is a debate on the chromosomal position of the Pii gene, because it was originally mapped on chromosome 6, but recent work showed it might be located on chromosome 9. To determine the chromosomal location of the Pi15 gene, a linkage analysis using molecular markers was performed in a F2 mapping population consisting of 15 resistant and 141 susceptible plants through bulked-segregant analysis (BSA) in combination with recessive-class analysis (RCA). Out of 20 microsatellite markers mapped on chromosomes 6 and 9 tested, only one marker, RM316 on chromosome 9, was found to have a linkage with the Pi15 gene with a recombination frequency of (19.1 ±3.7)%. To confirm this finding, four sequence-tagged site (STS) markers mapped on chromosome 9 were tested. The results suggested that marker G103 was linked to the Pi15 gene with a recombination frequency of (5.7±2.1)%. To find marker(s) more closely linked to the Pi15 gene, random amplified polymorphic DNA (RAPD) analysis was performed. Out of 1 000 primers tested, three RAPD markers, BAPi15486, BAPi15782 and BAPil5844 were found to tightly flank the Pi15 gene with recombination frequencies of 0.35%, 0.35% and 1.1%, respectively. These three RAPD markers should be viewed as the starting points for marker-aided gene pyramiding and cloning. A new gene cluster of rice blast resistance on chromosome 9 was also discussed.
基金Supported by International Science and Technology Cooperation Project of China(2012DFA31120)Special Fund for Agro-scientific Research in the Public Interest(201303094)National Key Technology Research and Development Program(2012BAD14B15)~~
文摘[Objective] The large-scale single-column fattening pig house with fermen- tation bed could hold 1 500 heads of fattening pigs. Since the number of pigs in piggery is too large, the management is difficult. The behavior of feeding, drinking, movement, sleeping, fighting of pigs is difficult to handle. The pigs cannot be man- aged well, resulting in the enhanced weakness of piglets, enhanced illness of weak pigs and missing treatment of ill pigs. The management for the pig populations is not satisfactory, and thus, it is needed to improve timely. [Method] The barriers for the fattening pigs in the large-scale pig house with fermentation bed were designed. The single management for single fattening pig was proposed. The large-scale fat- tening pig house was divided into 8 regions. Among them, 4 regions were located in both sides of the fermentation bed. Their main function was to separate ill, weak, small and bad pigs. In addition, the main column was divided into 4 gradual barri- ers. They were used to separate different-size fattening pigs. In view of manage- ment, the different-type pigs were managed dividedly with the gradual barriers. The equally-sized pigs were concentrated into one column. The ill, weak, small and bad pigs were isolated into barriers. Thus, the dynamic management was adopted. Until the fattening pigs grew up to 75 kg and their health was stable, the barriers among the columns were canceled to mix the pigs again and guarantee the pigs more gymnastic space. [Result] This design would improve the disease resistance of ill pigs, health status of weak pigs and management level of pig populations. This study would also provide a basis for the healthy running of large-scale fattening pig house with fermentation bed. [Conclusion] The pig-raising model with fermentation bed would improve the environment of pig house and the welfare of pigs. In addi- tion, the performance of pigs and quality of pork were also improved. The fermen- tation bed had an obvious advantage in safety and economics, and it had a broad application prospect.
文摘According to the survey of Guangdong mangrove resource in 2001 and authors field investigations in the past 5 years, the total mature mangrove land area of Guangdong Province was estimated at 9084 hm2, accounting for 41.4% of total mangrove land area of China. These mangrove forests totally consisted of 50 species belonging to 28 families, distributed at more than 100 locations along the coastlines of Guangdong and most of them present a high dense and dwarf appearance. The Ass. Avicennia marina is the most dominant mangrove association. The investigation results showed that the mangrove forests with coverage rates above 0.7 accounted for 68.0% of the total mangrove land area of the province and 77.8% of mangrove forests was less than 2 m in tree height. Since 1950, 54.6% of mangrove forests have disappeared due to paddy rice reclaim, aquaculture and city constructions. Derivational conservation efforts are still weakly empowered and should be strengthened intensively. The author suggested that mangrove laws and regulations should be enforced, mangrove scientific research should be strengthened; and mangrove conservation awareness of local community should be raised on conservation of mangroves.
文摘A complete approximate symmetry classification of a class of perturbed nonlinear wave equations isperformed using the method originated from Fushchich and Shtelen.Moreover,large classes of approximate invariantsolutions of the equations based on the Lie group method are constructed.
文摘The train schedule usually includes train stop schedule,routing scheme and formation scheme.It is the basis of subway transportation.Combining the practical experience of transport organizations and the principle of the best match between transport capacity and passenger flow demand,taking the minimum value of passenger travel costs and corporation operating costs as the goal,considering the constraints of the maximum rail capacity,the minimum departure frequency and the maximum available electric multiple unit,an optimization model for city subway Y-type operation mode is constructed to determine the operation section of mainline as well as branch line and the train frequency of the Y-type operation mode.The particle swarm optimization(PSO)algorithm based on classification learning is used to solve the model,and the effectiveness of the model and algorithm is verified by a practical case.The results show that the length of branch line in Y-type operation affects the cost of waiting time of passengers significantly.
文摘Lie group method provides an efficient tool to solve nonlinear partial differential equations. This paper suggests Lie group method for fractional partial differential equations. A time-fractional Burgers equation is used as an example to illustrate the effectiveness of the Lie group method and some classes of exact solutions are obtained.
