Based on a simple nonrelativistic constituent quark model, the nucleon structure function F<SUB>2</SUB> in the resonance region is estimated by taking the contributions from low-lying nucleon resonances in...Based on a simple nonrelativistic constituent quark model, the nucleon structure function F<SUB>2</SUB> in the resonance region is estimated by taking the contributions from low-lying nucleon resonances into account. Calculated results are employed to study quark-hardon duality in the nucleon electron scattering process by comparing them to the scaling behavior from the data in deep inelastic scattering region.展开更多
The ability to recognise video events has become increasingly more popular owing to its extensive practical applications.Most events will occur in certain scene with certain people,and the scene context and group cont...The ability to recognise video events has become increasingly more popular owing to its extensive practical applications.Most events will occur in certain scene with certain people,and the scene context and group context provide important information for event recognition.In this paper,we present an algorithm to recognise video events in different scenes in which there are multiple agents.First,we recognise events for each agent based on Stochastic Context Sensitive Grammar(SCSG).Then we propose the model of a scene in order to infer the scene in which the events occur,and we use a co-occurrence matrix of events to represent the group context.Finally,the scene and group context are exploited to distinguish events having similar structures.Experimental results show that by adding the scene and group context,the performance of events recognition can be significantly improved.展开更多
In this study, one mononuclear zinc（II） complex with 1,2-bis CAP （（5-chlorosalicylidene amino）-phenylene）： C22C13N2035Znl5 H0125 （Zn-CAP） was synthesized. The binding properties of Zn-CAP with G-quadruplex DN...In this study, one mononuclear zinc（II） complex with 1,2-bis CAP （（5-chlorosalicylidene amino）-phenylene）： C22C13N2035Znl5 H0125 （Zn-CAP） was synthesized. The binding properties of Zn-CAP with G-quadruplex DNA and ctDNA （calf thymus DNA） were examined by fluorescence, CD （circular dichroism） spectroscopic and FRET （fluorescence resonance energy transfer） assay. In the fluorescence emission spectral analysis, the addition of three series of G-quadruplex DNA （G4-HTG21, G4-Pu27 and G4-c-kit-l） into the Zn-CAP solution induced moderate or add hypochromicity with total quenching ratios of 10.73%, 15.07% and 8.59% in the presence of K＋ were achieved, respectively. While the addition of ctDNA under same condition only caused 7.08% quenching on the fluorescence emission of Zn-CAP. In the CD spectral analysis, the interaction with Zn-CAP could induce significant spectral changes on the CD absorption of G4-HTG21, G4-Pu27 and G4-c-kit-1, with 106.00%, 93.06%, 113.47% increment at 232 nm absorption, along with a 81.11%, 92.80%, 83.72% decrement at 295 nm or 270 nm absorption, which demonstrated that the antiparallel structure of G-quadruplex DNA is more stable in the presence of Zn-CAP. Comparatively, the addition of Zn-CAP could induce significant spectral changes on the CD absorption of double helix ctDNA, with 64.17% decrement on the positive peak absorption, along with a 90.91% increment on the negative peak absorption. On the other hand, in the FRET-melting assay analysis, it was clear that Zn-CAP at 0.5 equivalences could raise the melting temperature of G-quadruplex （F2 IT or FPul 8T） by 3.45℃ and 15.85℃, indicating an obvious stabilization effect of Zn-CAP on G-quadruplex in Pu27. All the results indicated that Zn-CAP exhibited higher binding affinity and binding intensity to G-quadruplex DNA than ctDNA, especially G-quadruplex Pu27.展开更多
First evidence of a structure in the J/ψΛinvariant mass distribution is obtained from an amplitude analysis of■b^(-)J/ψΛK^(-)decays.The observed structure is consistent with being due to a charmonium pentaquark w...First evidence of a structure in the J/ψΛinvariant mass distribution is obtained from an amplitude analysis of■b^(-)J/ψΛK^(-)decays.The observed structure is consistent with being due to a charmonium pentaquark with strangeness with a significance of 3.1r including systematic uncertainties and lookelsewhere effect.Its mass and width are determined to be 4458:8±2:9t4:7-1:1 MeV and 17:3±6:5t8:0-5:7 MeV,respectively,where the quoted uncertainties are statistical and systematic.The structure is also consistent with being due to two resonances.In addition,the narrow excited■^(-)states,N■(1690)and■(1820),are seen for the first time in a■b^(-)decay,and their masses and widths are measured with improved precision.The analysis is performed using pp collision data corresponding to a total integrated luminosity of 9 fb^(-1),collected with the LHCb experiment at centre-of-mass energies of 7,8 and 13 TeV.展开更多
Supramolecular dendritic polymers（SDPs）provide a new opportunity for the precision diagnosis and treatment of diseases. SDPs are a novel class of non-covalently bonded macromolecules with highly branched structure a...Supramolecular dendritic polymers（SDPs）provide a new opportunity for the precision diagnosis and treatment of diseases. SDPs are a novel class of non-covalently bonded macromolecules with highly branched structure and three-dimensional globular topology, which exhibit dynamic/reversible features and unique physical/chemical properties（e.g., high solubility, low viscosity, and numerous functional terminal groups）. The reversibility of non-covalent interactions endows SDPs with the ability of facile preparation, smart responsiveness, and simple metabolism. These special characteristics determine the properties of SDPs, which are the key points for theranostic applications, including diagnosis,therapy, and theranostics. In this review, we briefly summarize the design and synthesis of SDPs with aimed structures,properties, functions as well as their present diagnostic and theranostic applications. These developments on the preparation and applications of SDPs for diagnostic and theranostic purpose promote interdisciplinary research fields of chemistry, material and biomedical science.展开更多
文摘Based on a simple nonrelativistic constituent quark model, the nucleon structure function F<SUB>2</SUB> in the resonance region is estimated by taking the contributions from low-lying nucleon resonances into account. Calculated results are employed to study quark-hardon duality in the nucleon electron scattering process by comparing them to the scaling behavior from the data in deep inelastic scattering region.
基金partially supported by the National Natural Science Foundation of China under Grant No.61203291the Specialised Research Fund for the Doctoral Program under Grant No.20121101110035
文摘The ability to recognise video events has become increasingly more popular owing to its extensive practical applications.Most events will occur in certain scene with certain people,and the scene context and group context provide important information for event recognition.In this paper,we present an algorithm to recognise video events in different scenes in which there are multiple agents.First,we recognise events for each agent based on Stochastic Context Sensitive Grammar(SCSG).Then we propose the model of a scene in order to infer the scene in which the events occur,and we use a co-occurrence matrix of events to represent the group context.Finally,the scene and group context are exploited to distinguish events having similar structures.Experimental results show that by adding the scene and group context,the performance of events recognition can be significantly improved.
文摘In this study, one mononuclear zinc（II） complex with 1,2-bis CAP （（5-chlorosalicylidene amino）-phenylene）： C22C13N2035Znl5 H0125 （Zn-CAP） was synthesized. The binding properties of Zn-CAP with G-quadruplex DNA and ctDNA （calf thymus DNA） were examined by fluorescence, CD （circular dichroism） spectroscopic and FRET （fluorescence resonance energy transfer） assay. In the fluorescence emission spectral analysis, the addition of three series of G-quadruplex DNA （G4-HTG21, G4-Pu27 and G4-c-kit-l） into the Zn-CAP solution induced moderate or add hypochromicity with total quenching ratios of 10.73%, 15.07% and 8.59% in the presence of K＋ were achieved, respectively. While the addition of ctDNA under same condition only caused 7.08% quenching on the fluorescence emission of Zn-CAP. In the CD spectral analysis, the interaction with Zn-CAP could induce significant spectral changes on the CD absorption of G4-HTG21, G4-Pu27 and G4-c-kit-1, with 106.00%, 93.06%, 113.47% increment at 232 nm absorption, along with a 81.11%, 92.80%, 83.72% decrement at 295 nm or 270 nm absorption, which demonstrated that the antiparallel structure of G-quadruplex DNA is more stable in the presence of Zn-CAP. Comparatively, the addition of Zn-CAP could induce significant spectral changes on the CD absorption of double helix ctDNA, with 64.17% decrement on the positive peak absorption, along with a 90.91% increment on the negative peak absorption. On the other hand, in the FRET-melting assay analysis, it was clear that Zn-CAP at 0.5 equivalences could raise the melting temperature of G-quadruplex （F2 IT or FPul 8T） by 3.45℃ and 15.85℃, indicating an obvious stabilization effect of Zn-CAP on G-quadruplex in Pu27. All the results indicated that Zn-CAP exhibited higher binding affinity and binding intensity to G-quadruplex DNA than ctDNA, especially G-quadruplex Pu27.
文摘First evidence of a structure in the J/ψΛinvariant mass distribution is obtained from an amplitude analysis of■b^(-)J/ψΛK^(-)decays.The observed structure is consistent with being due to a charmonium pentaquark with strangeness with a significance of 3.1r including systematic uncertainties and lookelsewhere effect.Its mass and width are determined to be 4458:8±2:9t4:7-1:1 MeV and 17:3±6:5t8:0-5:7 MeV,respectively,where the quoted uncertainties are statistical and systematic.The structure is also consistent with being due to two resonances.In addition,the narrow excited■^(-)states,N■(1690)and■(1820),are seen for the first time in a■b^(-)decay,and their masses and widths are measured with improved precision.The analysis is performed using pp collision data corresponding to a total integrated luminosity of 9 fb^(-1),collected with the LHCb experiment at centre-of-mass energies of 7,8 and 13 TeV.
基金financially supported by the National Natural Science Foundation of China (51690151, 51503122, 21374062 and 51473093)National Basic Research Program (2015CB931801)
文摘Supramolecular dendritic polymers（SDPs）provide a new opportunity for the precision diagnosis and treatment of diseases. SDPs are a novel class of non-covalently bonded macromolecules with highly branched structure and three-dimensional globular topology, which exhibit dynamic/reversible features and unique physical/chemical properties（e.g., high solubility, low viscosity, and numerous functional terminal groups）. The reversibility of non-covalent interactions endows SDPs with the ability of facile preparation, smart responsiveness, and simple metabolism. These special characteristics determine the properties of SDPs, which are the key points for theranostic applications, including diagnosis,therapy, and theranostics. In this review, we briefly summarize the design and synthesis of SDPs with aimed structures,properties, functions as well as their present diagnostic and theranostic applications. These developments on the preparation and applications of SDPs for diagnostic and theranostic purpose promote interdisciplinary research fields of chemistry, material and biomedical science.
