OBJECTIVE To investigate the expression of the RECK gene in human breast (cancer) cell lines, and to determine the relationship between RECK gene expression and the invasive capacity of the breast cancer cell lines. M...OBJECTIVE To investigate the expression of the RECK gene in human breast (cancer) cell lines, and to determine the relationship between RECK gene expression and the invasive capacity of the breast cancer cell lines. METHODS The invasive capacity of breast (cancer) cell lines including HBL-100, MCF-7 and MDA-MB-435S were determined by the Tran-swell method. The protein expression levels of RECK, MMP-2 and MMP-9 genes in these three cell lines were measured by immunocytochemical methods. The expressions of the RECK gene and protein level were measured by RT-PCR and Western blots in the cell lines respectively. RESULTS The order of the invasive capacity of the breast (cancer) cell lines was MDA-MB-435S, being the highest, and HBL-100, being the lowest. The invasive capacity difference between any two groups among the three groups was significant (P<0.01). The protein expression level of the RECK gene in the HBL-100 cell line was highest, and no expression was detected in MDA-MB-435S cells. Moreover, the expression of the RECK gene was negatively correlated with the expression of the MMP-2 and MMP-9 genes. The mRNA level of the RECK gene in HBL-100 cells was the highest, but no expression was found in the MDA-MB-435S cells (P<0.001). CONCLUSION There was a significant negative correlation between the expression level of the RECK gene and invasive capacity in vitro, and the RECK gene expression showed an inverse proportion to that of the MMP-2, MMP-9 genes.展开更多
Transparent glass has been identified as a vital medium for three-dimensional(3D)optical information storage and multi-level encryption.However,it has remained a challenge for directly writing 3D patterning inside a t...Transparent glass has been identified as a vital medium for three-dimensional(3D)optical information storage and multi-level encryption.However,it has remained a challenge for directly writing 3D patterning inside a transparent glass using semiconductor blue laser instead of high-cost femtosecond laser.Here,we demonstrate that rare earth ions doped transparent glass can be used as 3D optical information storage and data encryption medium based on their reversible transmittance and photoluminescence manipulation.The color of tungsten phosphate glass doped with rare earth ions change reversibly from light yellow to blue upon alternating 473 nm laser illumination and temperature stimulation,resulting in the reversible luminescence modulation.The information data could be repeatedly written and erased in arbitrary 3D space of transparent glass,not only showing the ability of the excellent reproducibility and storage capacity,but also opening opportunities in information security.The present work expands the application fields of luminescent glass,and it is conducive to develop a novel 3D data storage and information encryption media.展开更多
Exploring a new tuning way to facilely realize single-band red emission in trivalent rare-earth ions(RE3+) doped upconversion(UC) materials is still desirable.In this work,the intense single-band red emission is achie...Exploring a new tuning way to facilely realize single-band red emission in trivalent rare-earth ions(RE3+) doped upconversion(UC) materials is still desirable.In this work,the intense single-band red emission is achieved by co-doping only Ho3+in the BiOCl:Er3+ under 1550 nm excitation.In the BiOCl layered host,co-doping Ho3+can further enhance the red emission and simultaneously suppress the green emission of Er3+,and thus obviously improve the red-to-green(R/G) ratio.It is found that Ho3+does not se rve as ene rgy trapping through the 5 I6 state as in traditional UC materials but acts as ET bridge(4 S3/2,2 H11/2(Er3+)→5 F4,5 S2(Ho3+)→4 F9/2(Er3+)).The tuning mechanism of Ho3+is discussed in detail and further confirms through a comparative experiment.Our research gives an unusual perspective to tune the UC behavior of Er3+through co-doping Ho3+,which might be inspiring for achievement of single-band red UC emission.展开更多
The process of formation reconfiguration for close-range satellite formation should take into account the risk of collisions between satellites.To this end,this paper presents a method to rapidly generate low-thrust c...The process of formation reconfiguration for close-range satellite formation should take into account the risk of collisions between satellites.To this end,this paper presents a method to rapidly generate low-thrust collision-avoidance trajectories in the formation reconfiguration using Finite Fourier Series(FFS).The FFS method can rapidly generate the collision-avoidance threedimensional trajectory.The results obtained by the FFS method are used as an initial guess in the Gauss Pseudospectral Method(GPM)solver to verify the applicability of the results.Compared with the GPM method,the FFS method needs very little computing time to obtain the results with very little difference in performance index.To verify the effectiveness,the proposed method is tested and validated by a formation control testbed.Three satellite simulators in the testbed are used to simulate two-dimensional satellite formation reconfiguration.The simulation and experimental results show that the FFS method can rapidly generate trajectories and effectively reduce the risk of collision between satellites.This fast trajectory generation method has great significance for on-line,constantly satellite formation reconfiguration.展开更多
For better use of solar energy,the development of efficient broadband photocatalyst has attracted extraordinary attention.In this study,a ternary composite consisting of Sr_(2)LaF_(7)∶Yb^(3+),Er^(3+)upconversion(UC)n...For better use of solar energy,the development of efficient broadband photocatalyst has attracted extraordinary attention.In this study,a ternary composite consisting of Sr_(2)LaF_(7)∶Yb^(3+),Er^(3+)upconversion(UC)nanocrystals and Bi nanoparticles loaded BiOBr nanosheets with oxygen vacancies(OVs,SLFBB)was designed and synthesized by multi-step solvent-thermal method.Mechanisms of in-situ formation of Bi nanoparticles and OVs in BiOBr/Sr_(2)LaF_(7)∶Yb^(3+),Er^(3+)composites(SFLB)are clarified.The Bi metal and OVs enhanced the light-harvesting capacity in the region of visible-near-infrared(Vis-NIR),and promoted the separation of electron-hole(e-/h+)pairs.Furthermore,the surface plasmon resonance(SPR)effect of Bi metal can improve the energy transfer from Sr_(2)LaF_(7)∶Yb^(3+),Er^(3+)to BiOBr via nonradiative energy transfer process,resulting in enhancing the light utilization from up-converting NIR into Vis light.Due to the synergistic effects of UC function,SPR and OVs,the SFLBB exhibited obviously enhanced photocatalytic ability for the degradation of BPA with a rate of 8.9×10^(-3) min^(-1),which is about 2.78 times higher than 3.2×10^(-3) min^(-1) of BiOBr(BOB)under UV-Vis-NIR light irradiation.This work provides a novel strategy for the project of high-efficiency Bismuth-based broadband photocatalysts,which is helpful to fur-ther understand the mechanism of enhanced photocatalysis by UC function and plasmonic effect.展开更多
Dear Editor,Tungsten-based photochromic materials are well known,suchastungsten-phosphateglasses,tungsten-telluriteglasses,andtungsten-borateglasses'.Photoluminescence glasses exhibit a wide range of application i...Dear Editor,Tungsten-based photochromic materials are well known,suchastungsten-phosphateglasses,tungsten-telluriteglasses,andtungsten-borateglasses'.Photoluminescence glasses exhibit a wide range of application in the fields of display,lighting,laser and optical thermometry,et al.Combination of photochromic and luminescence can extend the application of luminescence materials2-7.Our focus is not on the development of new photochromic materials,but on the control of luminescence through photochromic reaction,especially achieved the real complex threedimensional patterns using laser directly writing technology in photo-modulated transparent glass.In our work2,the three-dimensional optical data storage and information encryption application of photochromic glass with luminescence was obtained.展开更多
Photonic crystal heterostructures composed of YbPO4:Er^(3+) inverse opal and polystyrene opal were prepared via a template-assisted process, which exhibited two photonic band gaps. The microstructure,phase and opt...Photonic crystal heterostructures composed of YbPO4:Er^(3+) inverse opal and polystyrene opal were prepared via a template-assisted process, which exhibited two photonic band gaps. The microstructure,phase and optical properties of photonic crystal heterostructures were investigated by x-ray diffraction,scanning electron microscopy, fluorescence spectroscopy, absorption spectroscopy, fluorescence lifetime,etc. The upconversion emission suppression caused by single photonic band gap from the following YbPO4:Er^(3+) inverse opal or the upper opal was observed. The upconversion luminescence was strongly suppressed due to the two photonic band gap overlapping effect caused by the following YbPO4:Er^(3+) inverse opal or the upper opal. The modified mechanisms of upconversion luminescence were discussed by the upconversion luminescence lifetime of YbPO4:Er^(3+) photonic crystal heterostructures. The results demonstrated the modified upconversion luminescence is attributed to the photon trapping caused by Bragg reflection of photonic crystal heterostructures.展开更多
BiOCl crystal shows potential as efficient optical host due to its special layered structure. Here,the luminescence properties of the Er^3+/Sm^3+ co-doped BiOCl phosphors as single-phase phosphors were reported. Upo...BiOCl crystal shows potential as efficient optical host due to its special layered structure. Here,the luminescence properties of the Er^3+/Sm^3+ co-doped BiOCl phosphors as single-phase phosphors were reported. Upon near ultraviolet excitation(NUV, 380 nm corresponding the ^4 I15/2→ ^4 G11/2 transition of Er^3+ ions), the phosphors exhibit the efficient characteristic emissions of Er^3+ and Sm^3+ ions simultaneously. The energy transfer(ET) from Er^3+ to Sm^3+ ions in the layered crystals has been validated by the variation of emission intensities and decay lifetimes respectively, which is ascribed to be a dipoledipole interaction. By virtue of the ET behavior and increasing Sm^3+ ion concentration, the enhancing emission intensity of Sm^3+ and the tunability of emission color from yellowish-green(0.318, 0.420) to white(0.343, 0.347) are realized. The results of our work indicate that the Er^3+/Sm^3+ co-doped BiOCI phosphor has a promising application serving as single component white emitting phosphors for NUV excited WLEDs.展开更多
文摘OBJECTIVE To investigate the expression of the RECK gene in human breast (cancer) cell lines, and to determine the relationship between RECK gene expression and the invasive capacity of the breast cancer cell lines. METHODS The invasive capacity of breast (cancer) cell lines including HBL-100, MCF-7 and MDA-MB-435S were determined by the Tran-swell method. The protein expression levels of RECK, MMP-2 and MMP-9 genes in these three cell lines were measured by immunocytochemical methods. The expressions of the RECK gene and protein level were measured by RT-PCR and Western blots in the cell lines respectively. RESULTS The order of the invasive capacity of the breast (cancer) cell lines was MDA-MB-435S, being the highest, and HBL-100, being the lowest. The invasive capacity difference between any two groups among the three groups was significant (P<0.01). The protein expression level of the RECK gene in the HBL-100 cell line was highest, and no expression was detected in MDA-MB-435S cells. Moreover, the expression of the RECK gene was negatively correlated with the expression of the MMP-2 and MMP-9 genes. The mRNA level of the RECK gene in HBL-100 cells was the highest, but no expression was found in the MDA-MB-435S cells (P<0.001). CONCLUSION There was a significant negative correlation between the expression level of the RECK gene and invasive capacity in vitro, and the RECK gene expression showed an inverse proportion to that of the MMP-2, MMP-9 genes.
基金financially supported by the National Natural Science Foundation of High-end Foreign Experts Introduction Plan(G2022039008L)the Key Project of the National Natural Science Foundation of China-Yunnan Joint Fund(U2102215)Yunnan Major Scientific and Technological Projects(202202AG050016)。
基金supported by the National Natural Science Foundation of China (51762029, 11674137)the Applied Basic Research Key Program of Yunnan Province (2018FA026)
基金the National Natural Science Foundation of China(51762029,62075063,51772101)the Applied Basic Research Key Program of Yunnan Province(2018FA026)the Key R&D Program of Guangzhou(202007020003).
文摘Transparent glass has been identified as a vital medium for three-dimensional(3D)optical information storage and multi-level encryption.However,it has remained a challenge for directly writing 3D patterning inside a transparent glass using semiconductor blue laser instead of high-cost femtosecond laser.Here,we demonstrate that rare earth ions doped transparent glass can be used as 3D optical information storage and data encryption medium based on their reversible transmittance and photoluminescence manipulation.The color of tungsten phosphate glass doped with rare earth ions change reversibly from light yellow to blue upon alternating 473 nm laser illumination and temperature stimulation,resulting in the reversible luminescence modulation.The information data could be repeatedly written and erased in arbitrary 3D space of transparent glass,not only showing the ability of the excellent reproducibility and storage capacity,but also opening opportunities in information security.The present work expands the application fields of luminescent glass,and it is conducive to develop a novel 3D data storage and information encryption media.
基金the National Natural Science Foundation of China(11874186)the Applied Basic Research Program of Yunnan Province(2017FB079)+1 种基金the Reserve Talents Project of Yunnan Province(2015HB013)the Scientific Research Foundation of the Education Department of Yunnan Province(2018JS452)。
文摘Exploring a new tuning way to facilely realize single-band red emission in trivalent rare-earth ions(RE3+) doped upconversion(UC) materials is still desirable.In this work,the intense single-band red emission is achieved by co-doping only Ho3+in the BiOCl:Er3+ under 1550 nm excitation.In the BiOCl layered host,co-doping Ho3+can further enhance the red emission and simultaneously suppress the green emission of Er3+,and thus obviously improve the red-to-green(R/G) ratio.It is found that Ho3+does not se rve as ene rgy trapping through the 5 I6 state as in traditional UC materials but acts as ET bridge(4 S3/2,2 H11/2(Er3+)→5 F4,5 S2(Ho3+)→4 F9/2(Er3+)).The tuning mechanism of Ho3+is discussed in detail and further confirms through a comparative experiment.Our research gives an unusual perspective to tune the UC behavior of Er3+through co-doping Ho3+,which might be inspiring for achievement of single-band red UC emission.
基金supported in part by the National Natural Science Foundation of China(Nos.11702072 and 11672093)。
文摘The process of formation reconfiguration for close-range satellite formation should take into account the risk of collisions between satellites.To this end,this paper presents a method to rapidly generate low-thrust collision-avoidance trajectories in the formation reconfiguration using Finite Fourier Series(FFS).The FFS method can rapidly generate the collision-avoidance threedimensional trajectory.The results obtained by the FFS method are used as an initial guess in the Gauss Pseudospectral Method(GPM)solver to verify the applicability of the results.Compared with the GPM method,the FFS method needs very little computing time to obtain the results with very little difference in performance index.To verify the effectiveness,the proposed method is tested and validated by a formation control testbed.Three satellite simulators in the testbed are used to simulate two-dimensional satellite formation reconfiguration.The simulation and experimental results show that the FFS method can rapidly generate trajectories and effectively reduce the risk of collision between satellites.This fast trajectory generation method has great significance for on-line,constantly satellite formation reconfiguration.
基金supported by the National Natural Science Foundation of China(51762029)the Applied Basic Research Key Program of Yunnan Province(2018FA026)the Key Project of the National Natural Science Foundation of China-Yunnan Joint Fund(U2102215)。
基金This work was supported by the National Natural Science Foundation of China(No.11874186)Foundation of Yunnan Province(No.2019HC016).
文摘For better use of solar energy,the development of efficient broadband photocatalyst has attracted extraordinary attention.In this study,a ternary composite consisting of Sr_(2)LaF_(7)∶Yb^(3+),Er^(3+)upconversion(UC)nanocrystals and Bi nanoparticles loaded BiOBr nanosheets with oxygen vacancies(OVs,SLFBB)was designed and synthesized by multi-step solvent-thermal method.Mechanisms of in-situ formation of Bi nanoparticles and OVs in BiOBr/Sr_(2)LaF_(7)∶Yb^(3+),Er^(3+)composites(SFLB)are clarified.The Bi metal and OVs enhanced the light-harvesting capacity in the region of visible-near-infrared(Vis-NIR),and promoted the separation of electron-hole(e-/h+)pairs.Furthermore,the surface plasmon resonance(SPR)effect of Bi metal can improve the energy transfer from Sr_(2)LaF_(7)∶Yb^(3+),Er^(3+)to BiOBr via nonradiative energy transfer process,resulting in enhancing the light utilization from up-converting NIR into Vis light.Due to the synergistic effects of UC function,SPR and OVs,the SFLBB exhibited obviously enhanced photocatalytic ability for the degradation of BPA with a rate of 8.9×10^(-3) min^(-1),which is about 2.78 times higher than 3.2×10^(-3) min^(-1) of BiOBr(BOB)under UV-Vis-NIR light irradiation.This work provides a novel strategy for the project of high-efficiency Bismuth-based broadband photocatalysts,which is helpful to fur-ther understand the mechanism of enhanced photocatalysis by UC function and plasmonic effect.
文摘Dear Editor,Tungsten-based photochromic materials are well known,suchastungsten-phosphateglasses,tungsten-telluriteglasses,andtungsten-borateglasses'.Photoluminescence glasses exhibit a wide range of application in the fields of display,lighting,laser and optical thermometry,et al.Combination of photochromic and luminescence can extend the application of luminescence materials2-7.Our focus is not on the development of new photochromic materials,but on the control of luminescence through photochromic reaction,especially achieved the real complex threedimensional patterns using laser directly writing technology in photo-modulated transparent glass.In our work2,the three-dimensional optical data storage and information encryption application of photochromic glass with luminescence was obtained.
基金Project supported by the National Natural Science Foundation of China(11674137)the Applied Basic Research Program of Yunnan Province(2014FB127)+1 种基金Reserve Talents Project of Yunnan Province(2012HB068)Talent Youth Science Foundation of College of Materials Science and Technology,Kunming University of Science and Technology(20140205)
文摘Photonic crystal heterostructures composed of YbPO4:Er^(3+) inverse opal and polystyrene opal were prepared via a template-assisted process, which exhibited two photonic band gaps. The microstructure,phase and optical properties of photonic crystal heterostructures were investigated by x-ray diffraction,scanning electron microscopy, fluorescence spectroscopy, absorption spectroscopy, fluorescence lifetime,etc. The upconversion emission suppression caused by single photonic band gap from the following YbPO4:Er^(3+) inverse opal or the upper opal was observed. The upconversion luminescence was strongly suppressed due to the two photonic band gap overlapping effect caused by the following YbPO4:Er^(3+) inverse opal or the upper opal. The modified mechanisms of upconversion luminescence were discussed by the upconversion luminescence lifetime of YbPO4:Er^(3+) photonic crystal heterostructures. The results demonstrated the modified upconversion luminescence is attributed to the photon trapping caused by Bragg reflection of photonic crystal heterostructures.
基金Project supported by the National Natural Science Foundation of China(No.61465006)the Reserve talents project of Yunnan Province(2015HB013)
文摘BiOCl crystal shows potential as efficient optical host due to its special layered structure. Here,the luminescence properties of the Er^3+/Sm^3+ co-doped BiOCl phosphors as single-phase phosphors were reported. Upon near ultraviolet excitation(NUV, 380 nm corresponding the ^4 I15/2→ ^4 G11/2 transition of Er^3+ ions), the phosphors exhibit the efficient characteristic emissions of Er^3+ and Sm^3+ ions simultaneously. The energy transfer(ET) from Er^3+ to Sm^3+ ions in the layered crystals has been validated by the variation of emission intensities and decay lifetimes respectively, which is ascribed to be a dipoledipole interaction. By virtue of the ET behavior and increasing Sm^3+ ion concentration, the enhancing emission intensity of Sm^3+ and the tunability of emission color from yellowish-green(0.318, 0.420) to white(0.343, 0.347) are realized. The results of our work indicate that the Er^3+/Sm^3+ co-doped BiOCI phosphor has a promising application serving as single component white emitting phosphors for NUV excited WLEDs.