Hydrangea bretschneideri Dipp is a highly popular ornamental plant for garden decoration.Genetic engineering technology has been successfully used in many plant species,but it is limited in Hydrangea.Here we establish...Hydrangea bretschneideri Dipp is a highly popular ornamental plant for garden decoration.Genetic engineering technology has been successfully used in many plant species,but it is limited in Hydrangea.Here we established an efficient regeneration system by using stem segments as explants for the first time.In our study,the plant growth regulators(PGRs)were evaluated at the different regeneration processes,including axillary shoots regeneration and root induction.We found that the optimal concentration for axillary buds’induction was 2.0 mgL^(-1)6-BA and 0.5 mgL^(-1)1 IAA,its highest induction rate was 70%.Moreover,the highest axillary shoots proliferation coefficient was 10.7 on the Murashige and Skoog(MS)medium with 2.0 mgL^(-1)6-benzyladenine(BA),0.2 mgL^(-1)indole-3-butyric acid(IBA),and 1.0 mgL^(-1)gibberellin A3(GA3).The highest frequency of root induction was 80.0±0.06%by culturing the elongated shoots in 1/2 MS medium containing 0.1 mgL^(-1)IBA.In summary,our study will provide an effective technology for large-scale propagation and important pathway for promoting the popularization and application of Hydrangea bretschneideri Dipp.展开更多
Adventive regenerants of Populus × berolinensis Dipp. were obtained on 1/2 MS salts with sucrose, vitamins, BA, TDZ and NAA using stem, petiole and leaf explants. They differed from each other in plantlet dimensi...Adventive regenerants of Populus × berolinensis Dipp. were obtained on 1/2 MS salts with sucrose, vitamins, BA, TDZ and NAA using stem, petiole and leaf explants. They differed from each other in plantlet dimensions. More than 50 clones were produced from initial regenerants by excision and rooting of apexes and lateral shoots. Differences in stem length and thickness were observed between 200 field plants produced from in vitro plantlets. Differences in stem length were conditioned mainly due to different number of internodes and not by internodes’ lengths. Plants grown from cuttings excised from highest and smallest plants retained the abilities of mother plants to grow with different rates. It is concluded that somaclonal variability can be used for selection of fast growing poplar plants which are necessary for industrial plantations. These plants can be used for this purpose without the limitations existing for transgenic plants.展开更多
As the big data era is coming, it brings new challenges to the massive data processing. A combination of GPU and CPU on chip is the trend to release the pressure of large scale computing. We found that there are diffe...As the big data era is coming, it brings new challenges to the massive data processing. A combination of GPU and CPU on chip is the trend to release the pressure of large scale computing. We found that there are different memory access characteristics between GPU and CPU. The most important one is that the programs of GPU include a large number of threads, which lead to higher access frequency in cache than the CPU programs. Although the LRU policy favors the programs with high memory access frequency, the programs of GPU can’t get the corresponding performance boost even more cache resources are provided. So LRU policy is not suitable for heterogeneous multi-core processor. Based on the different characteristics of GPU and CPU programs on memory access, this paper proposes an LLC dynamic replacement policy--DIPP (Dynamic Insertion / Promotion Policy) for heterogeneous multi-core processors.The core idea of the replacement policy is to reduce the miss rate of the program and enhance the overall system performance by limiting the cache resources that GPU can acquire and reducing the thread interferences between programs. Experiments compare the DIPP replacement policy with LRU and we conduct a classified discussion according to the program results of GPU. Friendly programs enhance 23.29% on the average performance (using arithmetic mean).Large working sets programs can improve 13.95%, compute-intensive programs enhance 9.66% and stream class programs improve 3.8%.展开更多
基金This work is supported by the Grassland Talent Project:The Innovation Team of New Varieties Breeding at the Economic and Ecological Shrub,and the Evaluation of the Economic and Ecological Shrub Resources and New Variety Breeding in Inner Mongolia(No.201702077)。
文摘Hydrangea bretschneideri Dipp is a highly popular ornamental plant for garden decoration.Genetic engineering technology has been successfully used in many plant species,but it is limited in Hydrangea.Here we established an efficient regeneration system by using stem segments as explants for the first time.In our study,the plant growth regulators(PGRs)were evaluated at the different regeneration processes,including axillary shoots regeneration and root induction.We found that the optimal concentration for axillary buds’induction was 2.0 mgL^(-1)6-BA and 0.5 mgL^(-1)1 IAA,its highest induction rate was 70%.Moreover,the highest axillary shoots proliferation coefficient was 10.7 on the Murashige and Skoog(MS)medium with 2.0 mgL^(-1)6-benzyladenine(BA),0.2 mgL^(-1)indole-3-butyric acid(IBA),and 1.0 mgL^(-1)gibberellin A3(GA3).The highest frequency of root induction was 80.0±0.06%by culturing the elongated shoots in 1/2 MS medium containing 0.1 mgL^(-1)IBA.In summary,our study will provide an effective technology for large-scale propagation and important pathway for promoting the popularization and application of Hydrangea bretschneideri Dipp.
文摘Adventive regenerants of Populus × berolinensis Dipp. were obtained on 1/2 MS salts with sucrose, vitamins, BA, TDZ and NAA using stem, petiole and leaf explants. They differed from each other in plantlet dimensions. More than 50 clones were produced from initial regenerants by excision and rooting of apexes and lateral shoots. Differences in stem length and thickness were observed between 200 field plants produced from in vitro plantlets. Differences in stem length were conditioned mainly due to different number of internodes and not by internodes’ lengths. Plants grown from cuttings excised from highest and smallest plants retained the abilities of mother plants to grow with different rates. It is concluded that somaclonal variability can be used for selection of fast growing poplar plants which are necessary for industrial plantations. These plants can be used for this purpose without the limitations existing for transgenic plants.
文摘As the big data era is coming, it brings new challenges to the massive data processing. A combination of GPU and CPU on chip is the trend to release the pressure of large scale computing. We found that there are different memory access characteristics between GPU and CPU. The most important one is that the programs of GPU include a large number of threads, which lead to higher access frequency in cache than the CPU programs. Although the LRU policy favors the programs with high memory access frequency, the programs of GPU can’t get the corresponding performance boost even more cache resources are provided. So LRU policy is not suitable for heterogeneous multi-core processor. Based on the different characteristics of GPU and CPU programs on memory access, this paper proposes an LLC dynamic replacement policy--DIPP (Dynamic Insertion / Promotion Policy) for heterogeneous multi-core processors.The core idea of the replacement policy is to reduce the miss rate of the program and enhance the overall system performance by limiting the cache resources that GPU can acquire and reducing the thread interferences between programs. Experiments compare the DIPP replacement policy with LRU and we conduct a classified discussion according to the program results of GPU. Friendly programs enhance 23.29% on the average performance (using arithmetic mean).Large working sets programs can improve 13.95%, compute-intensive programs enhance 9.66% and stream class programs improve 3.8%.
