Objective:To study the influence of curcumin on chemosensitivity of nephroblastoma cells.Methods:Human nephroblastoma cells line SK-NEP-1 was transplanted to the nude mice subcutaneously to establish the implantation ...Objective:To study the influence of curcumin on chemosensitivity of nephroblastoma cells.Methods:Human nephroblastoma cells line SK-NEP-1 was transplanted to the nude mice subcutaneously to establish the implantation tumor model of human nephroblastoma cells.A total of 30 tumor-bearing mice were divided into three groups of ten randomly.The routine chemotherapy group was given vincristine(0.05 mg/mL·0.2 mL/d) and actinomycin D(15 ng/mL·0.2 mL/d) combined chemotherapy regime.The curcumin chemotherapy group was given the same combined chemotherapy regimens and curcumin(30 mg/kg/d) by intraperitoneal injection.The control group was given normal saline(NS) of the same volume by intraperitoneal injection.Continuous administration would be kept for 4 weeks and 3 days a week.The volumetric changes of every group were recorded.The serum of every group in different time was collected and the VEGF content was detected by ELISA.All mice were cercrificed and the tumor tissues were stripped and weighed after 4 weeks’ treatment.The tumor inhibition rate was calculated.The cell proliferation activity and apoptosis rate were detected by MTT and flow cytometry method.All data were statistically analyzed by SPSS 19.0.Results:The tumor volume,serum VEGF content,tumor inhibition rate,cell proliferation activity and apoptosis rate of routine chemotherapy group and curcumin chemotherapy group had significant differences comparing with the control group(P<0.05) after 4-week’s treatment.The cancer growth of curcumin chemotherapy group was obviously decreased and even tended to shrink comparing with routine chemotherapy group(χ2=15.732,P=0.007).The cell proliferation activity was significantly reduced and the apoptosis rate was significantly higher,(χ~2=9.427,P=0.012)which showing the effect of chemotherapy was enhanced.Conclusions:The chemosensitivity of nephroblastoma cells could be improved by curcumin,then the effect of preoperative adjuvant chemotherapy scheme would be enhanced,the growth of nephroblastoma cells would be inhibited and the surgical risk of nephroblastoma would be reduced.展开更多
Photosensitive fluorescent probes have become powerful tools in chemical biology and molecular biophysics,which are used to investigate cellular processes with high temporal and spatial resolution.Accordingly,photosen...Photosensitive fluorescent probes have become powerful tools in chemical biology and molecular biophysics,which are used to investigate cellular processes with high temporal and spatial resolution.Accordingly,photosensitive fluorescent probes,including photoactivatable,photoconvertible,and photoswitchable fluorophores,have been extensively developed during the past decade.The photoswitchable fluorophores have received much attention because they highlight cellular events clearly.This minireview summarizes recent advances of using reversibly photoswitchable fluorophores and their applications in innovative bioimaging.Photoswitchable fluorophores include photoswitchable fluorescent proteins,photoswitchable fluorescent organic molecules(dyes),and photoswitchable fluorescent nanoparticles.Several strategies have been developed to synthesize photoswitchable fluorophores,including engineering combination proteins,chemical synthesis,polymerization,and self-assembly.Here we concentrate on polymer nanoparticles with optically switchable emission properties:either fluorescence on/offor dualalternating-color fluorescence photoswitching.The essential mechanisms of fluorescence photoswitching enable different types of photoswitchable fluorophores to change emission intensity or wavelength(color)and thus validating the basis of the fluorescence on/offor dual-color photoswitching design.Generally the possible applications of any fluorophores are to label biological targets,followed by specific imaging.The newly developed photoswitchable fluorophores enable super-resolution fluorescence imaging because of their photosensitive emission.Finally,we summarize the important area regarding future research and development on photoswitchable fluorescent nanoparticles.展开更多
How to improve charging processes and suppress self-discharging processes has always been one of the key issues to achieve quantum batteries with high performance.Although a quantum battery is inevitably influenced by...How to improve charging processes and suppress self-discharging processes has always been one of the key issues to achieve quantum batteries with high performance.Although a quantum battery is inevitably influenced by composite environments,this situation is still little understood,particularly regarding the influence of the memory effect of the composite environments and the coupling between composite environments.In this work,we investigate the effects of the composite environments,composed of two identical parts each containing a single cavity mode decaying to a reservoir,on the charging and self-discharging processes of a quantum battery.We show that increasing the two-mode coupling can effectively enhance the charging performance(i.e.,the stored energy,the charging power,ergotropy)and restrain the self-discharging process(i.e.,suppressing the process of dissipating the energy).However,different from the effect of two-mode coupling,we reveal that the memory effect of the reservoir in this composite environment is unfavorable to the charging process of the quantum battery,which is in sharp contrast to previous studies where the memory effect can significantly improve the charging performance of a quantum battery.Our results may benefit to the realization of quantum batteries with high performance under the actual complex environmental noise.展开更多
Understanding of charge/energy exchange processes and interfacial interactions that occur between quantum dots (QDs) and the metal oxides is of critical importance to these QD-based optoelectronic devices. This work r...Understanding of charge/energy exchange processes and interfacial interactions that occur between quantum dots (QDs) and the metal oxides is of critical importance to these QD-based optoelectronic devices. This work reports on linear dipole behavior of single near-infrared emitting CdSeTe/ZnS core/shell QDs which are encased in indium tin oxide (ITO) semiconductor lianoparticles films. A strong polarization anisotropy in photohiminescence emission is observed by defocused wide-field imaging and polarization measuremen11echniques, and the average polarization degree is up to 0.45. A possible mechanism for the observation is presented in which the electrons, locating at single QD surface from ITO by electron transfer due to the equilibration of the Fermi levels, result in a significant Stark distortion of the QD electron/hole wavefunctions. The Stark distortion results in the linear polarization property of the single QDs. The investigation of linear dipole behavior for single QDs encased in ITO films would be helpful for further improving QD-based device performance.展开更多
We report an experimental investigation of the influence of surface charges on the emission polarization properties of single CdSe/CdS dot-in-rods(DRs),which is important for their polarization-based practical applica...We report an experimental investigation of the influence of surface charges on the emission polarization properties of single CdSe/CdS dot-in-rods(DRs),which is important for their polarization-based practical applications.By covering the single DRs with N-type semiconductor indium tin oxide(ITO)nanoparticles,the surface of single DRs is charged by ITO through interracial electron transfer.This is confirmed by the experimental observations of the reduced photoluminescence intensities and lifetimes as well as the suppressing blinking.It is found that the full width at half maximum of histogram of polarization degrees of the single DRs is broadened from 0.24(on glass)to 0.41(in ITO).In order to explain the exprimental results,the band-edge exciton fine structure of single DRs is calculated by taking into account the sample parameters,the emission polarization,and the surface charges.The calculation results show that the level ordering of the emitting states determines the polarization degrees tending to increase or decrease under the influence of surface electrons.The surface electrons can induce an increase in the spacing between the emitting levels to change the populations and thus change the polarization degrees.In addition,different numbers of surface electrons may randomly distribute on the long CdSe/CdS rods,leading to the heterogeneous influences on the single DRs causing the broadening of polarization degrees also.展开更多
Monolayer transition metal dichalcogenides have emerged as promising mat erials for opt oelectTonic and nanophotonic devices.However,the low photoluminescence(PL)quantum yield(QY)hinders their various potential applic...Monolayer transition metal dichalcogenides have emerged as promising mat erials for opt oelectTonic and nanophotonic devices.However,the low photoluminescence(PL)quantum yield(QY)hinders their various potential applications.Here we engineer and enhance the PL intensity of monolayer WS_(2)by femtosecond laser irradiation.More than two orders of magnitude enhancement of PL intensity as compared to the as-prepared sample is determined.Furthermore,the engineering time is shortened by three orders of magnitude as compared to the improvement of PL intensity by continuous-wave laser irradiation.Based on the evolution of PL spectra,we attribute the giant PL enhancement to the conversion from trion emission to exciton,as well as the improvement of the QY when exciton and trion are localized to the new-formed defects.We have created microstructures on the monolayer WS_(2)based on the enhancement of PL intensity,where the engineered structures can be stably stored for more than three years.This flexible approach with the feature of excellent long-term storage stability is promising for applications in information storage,display technology,and opto electronic devices.展开更多
We have synthesized a series of fluorene-based fluorophores, in which a central fluorene core has been modified with different peripheral arylene vinylene substituents that are able to activate aggregation-induced emi...We have synthesized a series of fluorene-based fluorophores, in which a central fluorene core has been modified with different peripheral arylene vinylene substituents that are able to activate aggregation-induced emission (AIE) characteristics. 9,9-Dioctylfluorene doubly end-capped at the 2,7-positions with triphenylethene groups, such as 4-(2,2-diphenylvinyl)phenyl (F1-(2,2)-HTPE) and 4-(1,2-dipbenylvinyl)phenyl (F1-(1,2)-HTPE) were synthesized and compared to the tetraphenylethene analogue (F1-TPE). Both FI-(2,2)-HTPE and F1-(1,2)-HTPE glow with a deep blue fluorescence in THF solution with emission maxima (λem) of 426 and 403 nm, respectively. The λem slightly red-shifts in the solid-state to 458 nm for F 1-(2,2)-HTPE and 437 nm for F 1-(1,2)-HTPE. The fluorescence quantum yields (ΦF) of F1-(2,2)-HTPE (ΦF=35.1%) and FI-(1,2)-HTPE (ΦF=26.2%) were found to be higher in solution compared to the near quenching of F 1-TPE (ΦF = 0.1%). Consequently, this results in weaker AIE-stability of F1-(2,2)-HTPE (αAIE= 1.5) and F1-(1,2)-HTPE (αAIE=1.9) compared to F1-TPE (αAIE=125), suggesting that four phenyl groups are necessary for efficient AIE-activity of these fluorene bridged arylene vinylene type materials In addition, decreasing the steric hindrance around the arylene vinylene moiety by removal of a phenyl ring is an- other method to decrease the AIE characteristics, in a similar manner to the commonly known "phenyl-locking". Non-polar triphenylethenes are poorer AlE materials than their tetraphenylethene analogues. Replacing the hydro- gen atom of F1-(2,2)-HTPE with a cyano group affords fluorene end-capped with 2,3,3-triphenylacrylonitrile (F1-TPAN), which boosts the AIE-effect to αAIE=90.5 and red-shifts the solid-state emission (λem=528 nm) with near quenching in THF solution (ΦF= 0.12%). X-ray crystallographic analysis of F1-TPAN indicates that the intro- duction of cyano groups can not only diminish the intramolecular steric hindrance in comparison of F1-TPE, but also improve the molecular cohesion ability via multiple C--H...N interactions.展开更多
The Kaczmarz algorithm is a common iterative method for solving linear systems.As an effective variant of Kaczmarz algorithm,the greedy Kaczmarz algorithm utilizes the greedy selection strategy.The two-subspace projec...The Kaczmarz algorithm is a common iterative method for solving linear systems.As an effective variant of Kaczmarz algorithm,the greedy Kaczmarz algorithm utilizes the greedy selection strategy.The two-subspace projection method performs an optimal intermediate projection in each iteration.In this paper,we introduce a new greedy Kaczmarz method,which give full play to the advantages of the two improved Kaczmarz algorithms,so that the generated iterative sequence can exponentially converge to the optimal solution.The theoretical analysis reveals that our algorithm has a smaller convergence factor than the greedy Kaczmarz method.Experimental results confirm that our new algorithm is more effective than the greedy Kaczmarz method for coherent systems and the two-subspace projection method for appropriate scale systems.展开更多
基金supported by Science and Technology research Project of Zhengzhou City(121PPTGG499-2)
文摘Objective:To study the influence of curcumin on chemosensitivity of nephroblastoma cells.Methods:Human nephroblastoma cells line SK-NEP-1 was transplanted to the nude mice subcutaneously to establish the implantation tumor model of human nephroblastoma cells.A total of 30 tumor-bearing mice were divided into three groups of ten randomly.The routine chemotherapy group was given vincristine(0.05 mg/mL·0.2 mL/d) and actinomycin D(15 ng/mL·0.2 mL/d) combined chemotherapy regime.The curcumin chemotherapy group was given the same combined chemotherapy regimens and curcumin(30 mg/kg/d) by intraperitoneal injection.The control group was given normal saline(NS) of the same volume by intraperitoneal injection.Continuous administration would be kept for 4 weeks and 3 days a week.The volumetric changes of every group were recorded.The serum of every group in different time was collected and the VEGF content was detected by ELISA.All mice were cercrificed and the tumor tissues were stripped and weighed after 4 weeks’ treatment.The tumor inhibition rate was calculated.The cell proliferation activity and apoptosis rate were detected by MTT and flow cytometry method.All data were statistically analyzed by SPSS 19.0.Results:The tumor volume,serum VEGF content,tumor inhibition rate,cell proliferation activity and apoptosis rate of routine chemotherapy group and curcumin chemotherapy group had significant differences comparing with the control group(P<0.05) after 4-week’s treatment.The cancer growth of curcumin chemotherapy group was obviously decreased and even tended to shrink comparing with routine chemotherapy group(χ2=15.732,P=0.007).The cell proliferation activity was significantly reduced and the apoptosis rate was significantly higher,(χ~2=9.427,P=0.012)which showing the effect of chemotherapy was enhanced.Conclusions:The chemosensitivity of nephroblastoma cells could be improved by curcumin,then the effect of preoperative adjuvant chemotherapy scheme would be enhanced,the growth of nephroblastoma cells would be inhibited and the surgical risk of nephroblastoma would be reduced.
基金This work was supported in part by the Fundamental Research Funds for the Central Universities(HUST2010MS101),the NSFC(20874025)the Program for New Century Excellent Talents(NCET-07-00273)+1 种基金National Key Basic Research Program of China(2007CB310500)the National Science Foundation(NSF)Chemistry Division(CHE-0805547).
文摘Photosensitive fluorescent probes have become powerful tools in chemical biology and molecular biophysics,which are used to investigate cellular processes with high temporal and spatial resolution.Accordingly,photosensitive fluorescent probes,including photoactivatable,photoconvertible,and photoswitchable fluorophores,have been extensively developed during the past decade.The photoswitchable fluorophores have received much attention because they highlight cellular events clearly.This minireview summarizes recent advances of using reversibly photoswitchable fluorophores and their applications in innovative bioimaging.Photoswitchable fluorophores include photoswitchable fluorescent proteins,photoswitchable fluorescent organic molecules(dyes),and photoswitchable fluorescent nanoparticles.Several strategies have been developed to synthesize photoswitchable fluorophores,including engineering combination proteins,chemical synthesis,polymerization,and self-assembly.Here we concentrate on polymer nanoparticles with optically switchable emission properties:either fluorescence on/offor dualalternating-color fluorescence photoswitching.The essential mechanisms of fluorescence photoswitching enable different types of photoswitchable fluorophores to change emission intensity or wavelength(color)and thus validating the basis of the fluorescence on/offor dual-color photoswitching design.Generally the possible applications of any fluorophores are to label biological targets,followed by specific imaging.The newly developed photoswitchable fluorophores enable super-resolution fluorescence imaging because of their photosensitive emission.Finally,we summarize the important area regarding future research and development on photoswitchable fluorescent nanoparticles.
基金supported by the National Natural Science Foundation of China under grant Nos.12204348,12074027,11434015,61227902,61835013,11611530676,and KZ201610005011the National Key R&D Program of China under grant No.2016YFA0301500SPRPCAS under grant Nos.XDB01020300 and XDB21030300.
文摘How to improve charging processes and suppress self-discharging processes has always been one of the key issues to achieve quantum batteries with high performance.Although a quantum battery is inevitably influenced by composite environments,this situation is still little understood,particularly regarding the influence of the memory effect of the composite environments and the coupling between composite environments.In this work,we investigate the effects of the composite environments,composed of two identical parts each containing a single cavity mode decaying to a reservoir,on the charging and self-discharging processes of a quantum battery.We show that increasing the two-mode coupling can effectively enhance the charging performance(i.e.,the stored energy,the charging power,ergotropy)and restrain the self-discharging process(i.e.,suppressing the process of dissipating the energy).However,different from the effect of two-mode coupling,we reveal that the memory effect of the reservoir in this composite environment is unfavorable to the charging process of the quantum battery,which is in sharp contrast to previous studies where the memory effect can significantly improve the charging performance of a quantum battery.Our results may benefit to the realization of quantum batteries with high performance under the actual complex environmental noise.
基金the National Key R&D Program of China (No. 2017YFA0304203)the National Natural Science Foundation of China (Grant Nos. 61527824, 61675119, U1510133, 11434007, 11504216, and 61605104), PCSIRT (No. IRT_17R70)+1 种基金Y. Peng was supported by the National Natural Science Foundation of China (No. 11404189)H. Xie was supported by the National Natural Science Foundation of China (No. 11504260).
文摘Understanding of charge/energy exchange processes and interfacial interactions that occur between quantum dots (QDs) and the metal oxides is of critical importance to these QD-based optoelectronic devices. This work reports on linear dipole behavior of single near-infrared emitting CdSeTe/ZnS core/shell QDs which are encased in indium tin oxide (ITO) semiconductor lianoparticles films. A strong polarization anisotropy in photohiminescence emission is observed by defocused wide-field imaging and polarization measuremen11echniques, and the average polarization degree is up to 0.45. A possible mechanism for the observation is presented in which the electrons, locating at single QD surface from ITO by electron transfer due to the equilibration of the Fermi levels, result in a significant Stark distortion of the QD electron/hole wavefunctions. The Stark distortion results in the linear polarization property of the single QDs. The investigation of linear dipole behavior for single QDs encased in ITO films would be helpful for further improving QD-based device performance.
基金The project was sponsored by the National Key Research and Development Program of China(Grant No.2017YFA0304203)the National Natural Science Foundation of China(Grant Nos.61527824,61675119,11434007,61875109,and 61605104)PCSIRT(Grant No.IRT.17R70),1331KSC and 111 project(Grant No.D18001).
文摘We report an experimental investigation of the influence of surface charges on the emission polarization properties of single CdSe/CdS dot-in-rods(DRs),which is important for their polarization-based practical applications.By covering the single DRs with N-type semiconductor indium tin oxide(ITO)nanoparticles,the surface of single DRs is charged by ITO through interracial electron transfer.This is confirmed by the experimental observations of the reduced photoluminescence intensities and lifetimes as well as the suppressing blinking.It is found that the full width at half maximum of histogram of polarization degrees of the single DRs is broadened from 0.24(on glass)to 0.41(in ITO).In order to explain the exprimental results,the band-edge exciton fine structure of single DRs is calculated by taking into account the sample parameters,the emission polarization,and the surface charges.The calculation results show that the level ordering of the emitting states determines the polarization degrees tending to increase or decrease under the influence of surface electrons.The surface electrons can induce an increase in the spacing between the emitting levels to change the populations and thus change the polarization degrees.In addition,different numbers of surface electrons may randomly distribute on the long CdSe/CdS rods,leading to the heterogeneous influences on the single DRs causing the broadening of polarization degrees also.
基金Acknowledgements The project was sponsored by the National Basic Research Program of China (973 Program) (Grant No. 2012CB921603), the National Natural Science Foundation of China (Grant Nos. 61527824, 11434007, 11374196, 11404200, 11504216, and U1510133), PCSIRT (No. IRT13076), and the Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province.
基金supported by the National Key Research and Development Program of China(Grant No.2017YFA0304203)the National Natural Science Foundation of China(Nos.91950109,61875109,61527824,61675119)+1 种基金the Natural Science Foundation of Shanxi Province(No.201901D111010(ZD)),PCSIRT(No.IRT_17R70),1331KSC,PTITPostgraduate Education Innovation Project of Shanxi Province(Nos.2019SY052,2020BY022).
文摘Monolayer transition metal dichalcogenides have emerged as promising mat erials for opt oelectTonic and nanophotonic devices.However,the low photoluminescence(PL)quantum yield(QY)hinders their various potential applications.Here we engineer and enhance the PL intensity of monolayer WS_(2)by femtosecond laser irradiation.More than two orders of magnitude enhancement of PL intensity as compared to the as-prepared sample is determined.Furthermore,the engineering time is shortened by three orders of magnitude as compared to the improvement of PL intensity by continuous-wave laser irradiation.Based on the evolution of PL spectra,we attribute the giant PL enhancement to the conversion from trion emission to exciton,as well as the improvement of the QY when exciton and trion are localized to the new-formed defects.We have created microstructures on the monolayer WS_(2)based on the enhancement of PL intensity,where the engineered structures can be stably stored for more than three years.This flexible approach with the feature of excellent long-term storage stability is promising for applications in information storage,display technology,and opto electronic devices.
文摘We have synthesized a series of fluorene-based fluorophores, in which a central fluorene core has been modified with different peripheral arylene vinylene substituents that are able to activate aggregation-induced emission (AIE) characteristics. 9,9-Dioctylfluorene doubly end-capped at the 2,7-positions with triphenylethene groups, such as 4-(2,2-diphenylvinyl)phenyl (F1-(2,2)-HTPE) and 4-(1,2-dipbenylvinyl)phenyl (F1-(1,2)-HTPE) were synthesized and compared to the tetraphenylethene analogue (F1-TPE). Both FI-(2,2)-HTPE and F1-(1,2)-HTPE glow with a deep blue fluorescence in THF solution with emission maxima (λem) of 426 and 403 nm, respectively. The λem slightly red-shifts in the solid-state to 458 nm for F 1-(2,2)-HTPE and 437 nm for F 1-(1,2)-HTPE. The fluorescence quantum yields (ΦF) of F1-(2,2)-HTPE (ΦF=35.1%) and FI-(1,2)-HTPE (ΦF=26.2%) were found to be higher in solution compared to the near quenching of F 1-TPE (ΦF = 0.1%). Consequently, this results in weaker AIE-stability of F1-(2,2)-HTPE (αAIE= 1.5) and F1-(1,2)-HTPE (αAIE=1.9) compared to F1-TPE (αAIE=125), suggesting that four phenyl groups are necessary for efficient AIE-activity of these fluorene bridged arylene vinylene type materials In addition, decreasing the steric hindrance around the arylene vinylene moiety by removal of a phenyl ring is an- other method to decrease the AIE characteristics, in a similar manner to the commonly known "phenyl-locking". Non-polar triphenylethenes are poorer AlE materials than their tetraphenylethene analogues. Replacing the hydro- gen atom of F1-(2,2)-HTPE with a cyano group affords fluorene end-capped with 2,3,3-triphenylacrylonitrile (F1-TPAN), which boosts the AIE-effect to αAIE=90.5 and red-shifts the solid-state emission (λem=528 nm) with near quenching in THF solution (ΦF= 0.12%). X-ray crystallographic analysis of F1-TPAN indicates that the intro- duction of cyano groups can not only diminish the intramolecular steric hindrance in comparison of F1-TPE, but also improve the molecular cohesion ability via multiple C--H...N interactions.
基金supported by the National Natural Science Foundation of China(No.11771193).
文摘The Kaczmarz algorithm is a common iterative method for solving linear systems.As an effective variant of Kaczmarz algorithm,the greedy Kaczmarz algorithm utilizes the greedy selection strategy.The two-subspace projection method performs an optimal intermediate projection in each iteration.In this paper,we introduce a new greedy Kaczmarz method,which give full play to the advantages of the two improved Kaczmarz algorithms,so that the generated iterative sequence can exponentially converge to the optimal solution.The theoretical analysis reveals that our algorithm has a smaller convergence factor than the greedy Kaczmarz method.Experimental results confirm that our new algorithm is more effective than the greedy Kaczmarz method for coherent systems and the two-subspace projection method for appropriate scale systems.