This paper describes an approach to seek for mouse c-Myc/Myn proteins-bound specific sequences among ge-nomic DNA. cDNA fragment of myn gene was obtained through RT-PCR technique from RNA of NIH3T3 cells. DNA fragment...This paper describes an approach to seek for mouse c-Myc/Myn proteins-bound specific sequences among ge-nomic DNA. cDNA fragment of myn gene was obtained through RT-PCR technique from RNA of NIH3T3 cells. DNA fragments encoding BR/HLH/LZ structure of Myc and Myn proteins were cloned in frame into pGEX-2T vec-tor respectively Fusion GST-Myc and GST-Myn synthe-sized in E.coli hosts showed affinity to CACGTG E-boxDNA and subsequently interacted with genomic fragments prepared through whole-genome-PCR. A PCR-assisted procedure which combines protein-DNA interaction and affinity chromatography was designed to enrich Myc/Myn bound DNA. At least two genomic DNA fragments ob- tained exhibit specifical binding capacity to Myc/Myn complex but not to GST alone. Significance of the work and of the technique itself as well as identification of the DNAs are discussed.展开更多
Full-azimuth common reflection-angle gathers could be stacked at any azimuth. The stacked data at the azimuth perpendicular to fractures exhibit the largest azimuthal anisotropy, while the stacked data at the azimuth ...Full-azimuth common reflection-angle gathers could be stacked at any azimuth. The stacked data at the azimuth perpendicular to fractures exhibit the largest azimuthal anisotropy, while the stacked data at the azimuth parallel to fractures exhibit the smallest azimuthal anisotropy. In petroleum exploration in Block A, a neritic province in the Bohai Bay, we use the stacked data at the azimuth perpendicular to fractures to improve fault interpretation. We also use attribute fusion to identify fractures in different directions.展开更多
Surface modification of different functional molecules onto NaREF_(4)(RE=rare earth)upconversion nanoparticles(UCNPs)impart their multiple functionalities.Functional molecules can be loaded onto NaREF_(4) UCNPs throug...Surface modification of different functional molecules onto NaREF_(4)(RE=rare earth)upconversion nanoparticles(UCNPs)impart their multiple functionalities.Functional molecules can be loaded onto NaREF_(4) UCNPs through the formation of coordination bonds between the surface-exposed RE^(3+) ions and the appropriate chemical groups of functional molecules.The density of surface RE^(3+) ions directly determines the loading efficiency of Na REF4 UCNPs.However,NaREF_(4) is a binary cation system,rendering the surface-distributed Na;and RE^(3+) ions remains a mystery.Here,we develop an effective strategy to significantly enhance the density of surface RE^(3+) ions,thus maximizing the loading capacity of NaREF_(4) UCNPs.This strategy is based on a heterovalent cation exchange(HCE)reaction in the surface region in which Na^(+)ions are replaced by RE^(3+) ions.The density of surface ligands enhances from 3.6 to 8.8 molecules/nm^(2) after reaction,suggesting that the loading efficiency increases by approximately 150%.Benefiting from the improved loading capacity,we demonstrate such surface-RE-rich nanoparticles have the ability to offer higher colloidal stability and more desirable photodynamic therapy(PDT)efficacy.This work not only advances our understanding of cation exchange reactions in RE-based nanoparticles,but also provides significant value for considerable applications such as sensing,bioimaging,and therapy.展开更多
文摘This paper describes an approach to seek for mouse c-Myc/Myn proteins-bound specific sequences among ge-nomic DNA. cDNA fragment of myn gene was obtained through RT-PCR technique from RNA of NIH3T3 cells. DNA fragments encoding BR/HLH/LZ structure of Myc and Myn proteins were cloned in frame into pGEX-2T vec-tor respectively Fusion GST-Myc and GST-Myn synthe-sized in E.coli hosts showed affinity to CACGTG E-boxDNA and subsequently interacted with genomic fragments prepared through whole-genome-PCR. A PCR-assisted procedure which combines protein-DNA interaction and affinity chromatography was designed to enrich Myc/Myn bound DNA. At least two genomic DNA fragments ob- tained exhibit specifical binding capacity to Myc/Myn complex but not to GST alone. Significance of the work and of the technique itself as well as identification of the DNAs are discussed.
文摘Full-azimuth common reflection-angle gathers could be stacked at any azimuth. The stacked data at the azimuth perpendicular to fractures exhibit the largest azimuthal anisotropy, while the stacked data at the azimuth parallel to fractures exhibit the smallest azimuthal anisotropy. In petroleum exploration in Block A, a neritic province in the Bohai Bay, we use the stacked data at the azimuth perpendicular to fractures to improve fault interpretation. We also use attribute fusion to identify fractures in different directions.
基金financially supported by the National Natural Science Foundation of China(Nos.61805083,31801968,and 51802281)。
文摘Surface modification of different functional molecules onto NaREF_(4)(RE=rare earth)upconversion nanoparticles(UCNPs)impart their multiple functionalities.Functional molecules can be loaded onto NaREF_(4) UCNPs through the formation of coordination bonds between the surface-exposed RE^(3+) ions and the appropriate chemical groups of functional molecules.The density of surface RE^(3+) ions directly determines the loading efficiency of Na REF4 UCNPs.However,NaREF_(4) is a binary cation system,rendering the surface-distributed Na;and RE^(3+) ions remains a mystery.Here,we develop an effective strategy to significantly enhance the density of surface RE^(3+) ions,thus maximizing the loading capacity of NaREF_(4) UCNPs.This strategy is based on a heterovalent cation exchange(HCE)reaction in the surface region in which Na^(+)ions are replaced by RE^(3+) ions.The density of surface ligands enhances from 3.6 to 8.8 molecules/nm^(2) after reaction,suggesting that the loading efficiency increases by approximately 150%.Benefiting from the improved loading capacity,we demonstrate such surface-RE-rich nanoparticles have the ability to offer higher colloidal stability and more desirable photodynamic therapy(PDT)efficacy.This work not only advances our understanding of cation exchange reactions in RE-based nanoparticles,but also provides significant value for considerable applications such as sensing,bioimaging,and therapy.
