Streptococcus suis serotype 2(S.suis 2)is a zoonotic pathogen that clinically causes severe swine and human infections(such as meningitis,endocarditis,and septicemia).In order to cause widespread diseases in different...Streptococcus suis serotype 2(S.suis 2)is a zoonotic pathogen that clinically causes severe swine and human infections(such as meningitis,endocarditis,and septicemia).In order to cause widespread diseases in different organs,S.suis 2 must colonize the host,break the blood barrier,and cause exaggerated inflammation.In the last few years,most studies have focused on a single virulence factor and its influences on the host.Membrane vesicles(MVs)can be actively secreted into the extracellular environment contributing to bacteria-host interactions.Gram-negative bacteria-derived outer membrane vesicles(OMVs)were recently shown to activate host Caspase-11-mediated non-canonical inflammasome pathway via deliverance of OMV-bound lipopolysaccharide(LPS),causing host cell pyroptosis.However,little is known about the effect of the MVs from S.suis 2(Gram-positive bacteria without LPS)on cell pyroptosis.Thus,we investigated the molecular mechanism by which S.suis 2 MVs participate in endothelial cell pyroptosis.In this study,we used proteomics,electron scanning microscopy,fluorescence microscope,Western blotting,and bioassays,to investigate the MVs secreted by S.suis 2.First,we demonstrated that S.suis 2 secreted MVs with an average diameter of 72.04 nm,and 200 proteins in MVs were identified.Then,we showed that MVs were transported to cells via mainly dynamin-dependent endocytosis.The S.suis 2 MVs activated NLRP3/Caspase-1/GSDMD canonical inflammasome signaling pathway,resulting in cell pyroptosis,but it did not activate the Caspase-4/-5 pathway.More importantly,endothelial cells produce large amounts of reactive oxygen species(ROS)and lost their mitochondrial membrane potential under induction by S.suis 2 MVs.The results in this study suggest for the first time that MVs from S.suis 2 were internalized by endothelial cells via mainly dynamin-dependent endocytosis and might promote NLRP3/Caspase-1/GSDMD pathway by mitochondrial damage,which produced mtDNA and ROS under induction,leading to the pyroptosis of endothelial cells.展开更多
Biobutanol is an advanced biofuel that can be produced from excess lignocellulose via acetone-butanol-ethanol(ABE)fermentation.Although significant technological progress has been made in this field,attempts at larges...Biobutanol is an advanced biofuel that can be produced from excess lignocellulose via acetone-butanol-ethanol(ABE)fermentation.Although significant technological progress has been made in this field,attempts at largescale lignocellulosic ABE production remain scarce.In this study,1m^(3)scale ABE fermentation was investigated using high inhibitor tolerance Clostridium acetobutylicum ABE-P1201 and steam-exploded corn stover hydrolysate(SECSH).Before expanding the fermentation scale,the detoxification process for SECSH was simplified by process engineering.Results revealed that appropriate pH management during the fed-batch cultivation could largely decrease the inhibition of the toxic components in undetoxified SECSH to the solventogenesis phase of the ABE-P1201 strains,avoiding“acid crash”.Therefore,after naturalizing the pH by Ca(OH)_(2),the undetoxified SECSH,without removal of the solid components,reached 17.68±1.30 g/L of ABE production with 0.34±0.01 g/g of yield in 1 L scale bioreactor.Based on this strategy,the fermentation scale gradually expanded from laboratory-scale apparatus to pilot-scale bioreactors.Finally,17.05±1.20 g/L of ABE titer and 0.32±0.01 g/g of ABE yield were realized in 1m3 bioreactor,corresponding to approximately 145 kg of ABE production from 1 t of dry corn stover.The pilot-scale ABE fermentation demonstrated excellent stability during repeated operations.This study provided a simplified ABE fermentation strategy and verified the feasibility of the pilot process,providing tremendous significance and a solid foundation for the future industrialization of second-generation ABE plants.展开更多
The high peak power of picosecond pulses produced by a self-mode-locked semiconductor disk laser can effectively improve the efficiency of nonlinear frequency conversion.This paper presents the intracavity frequency t...The high peak power of picosecond pulses produced by a self-mode-locked semiconductor disk laser can effectively improve the efficiency of nonlinear frequency conversion.This paper presents the intracavity frequency tripling in a self-mode-locked semiconductor disk laser,and a picosecond pulse train at 327 nm wavelength is achieved.The pulse repetition rate is 0.49 GHz,and the pulse width is 5.0 ps.The obtained maximum ultraviolet output power under mode locking is 30.5 m W,and the corresponding conversion efficiency is obviously larger than that of continuous-wave operation.These ultraviolet picosecond pulses have high spatial and temporal resolution and can be applied in some emerging fields.展开更多
Inhibiting the irreversible escape of organic cations and iodide species in perovskite films is crucial for the fabrication of efficient and stable perovskite solar cells(PSCs).Here,we develop a reaction-and-assembly ...Inhibiting the irreversible escape of organic cations and iodide species in perovskite films is crucial for the fabrication of efficient and stable perovskite solar cells(PSCs).Here,we develop a reaction-and-assembly approach using monoamine zinc porphyrin(ZnP)to modify methylammonium(MA^+)lead iodide perovskite film.The amine group in ZnP reacts with MA^+and I^-ions to yield monoammonium zinc porphyrin(ZnP-H+I-).The resultant films show no escape of iodide when immersed in ether solutions.Measurements from space-charge limited currents and transient photoluminescence indicate the modified films have reduced density of defects.These results suggest the formed ZnP-H^+I^-is bound on the surface and grain boundary of perovskite film to retard migrations of ions.DFT calculations also show that the energy alignment between ZnP-H^+and perovskite facilitates the electron transfer and reduces charge recombination at the perovskite grains.Furthermore,post-treating the Zn Pdoped film with ZnP again results in the formation of a one dimension zig-zag coordination polymer on the surface of the perovskite film.The single crystal structure of ZnP shows the polymer layer is formed through the coordination interaction between the Zn(II)metal center and a neighboring monoamine.The polymer facilitates the interfacial charge transfer,and reduces the escape of organic cations and iodide species in perovskite films,thereby keeping the excellent cell performance(20.0%)and further realizing the ion encapsulation.Finally,the modified PSCs retain over 90%of its original efficiency over2,000 h at 85°C or AM 1.5 G continuous illumination,or over 6,000 h in 45%humidity without encapsulation.This work affords a new strategy to achieve the efficient ions immobilization and encapsulation by in situ reaction and coordination assembly of mono-amine zinc porphyrin.展开更多
The preparation of suitable hole transport material(HTM)is critical to the performance and stability of perovskite solar cells(PSCs)with low-cost.Herein,a mass producible and soluble copper phthalocyanine decorated wi...The preparation of suitable hole transport material(HTM)is critical to the performance and stability of perovskite solar cells(PSCs)with low-cost.Herein,a mass producible and soluble copper phthalocyanine decorated with butoxy donor groups(CuPcOBu)was designed as HTM and prepared by a facile two-step synthetic route.To generate high quality HTM film,4-tertbutylpyridine(tBP)was doped into CuPc-OBu to prepare the film and then removed by annealing.Such a t BP-assisted strategy resulted in the best efficiency of the PSCs with lead trihalide perovskite up to 19.0%(small-area of 0.1 cm^2)and 10.1%(the active area of 8.0 cm^2 for the module device).And the best efficiency of the tin-based PSCs with CuPc-OBu reached to 6.9%.More importantly,the device with CuPc-OBu as HTM revealed the remarkably enhanced stability.This work provides a new strategy to improve the film-quality of free-doping HTMs and enhance the efficiency and stability of Pb-and Sn-based PSCs with low-cost.展开更多
基金supported by the National Natural Science Foundation of China(U22A20520)the Innovation Team Project of Modern Agricultural Industrial Technology System of Guangdong Province,China(2023KJ119)the Natural Science Foundation Program of Guangdong Province,China(2023A1515012206)。
文摘Streptococcus suis serotype 2(S.suis 2)is a zoonotic pathogen that clinically causes severe swine and human infections(such as meningitis,endocarditis,and septicemia).In order to cause widespread diseases in different organs,S.suis 2 must colonize the host,break the blood barrier,and cause exaggerated inflammation.In the last few years,most studies have focused on a single virulence factor and its influences on the host.Membrane vesicles(MVs)can be actively secreted into the extracellular environment contributing to bacteria-host interactions.Gram-negative bacteria-derived outer membrane vesicles(OMVs)were recently shown to activate host Caspase-11-mediated non-canonical inflammasome pathway via deliverance of OMV-bound lipopolysaccharide(LPS),causing host cell pyroptosis.However,little is known about the effect of the MVs from S.suis 2(Gram-positive bacteria without LPS)on cell pyroptosis.Thus,we investigated the molecular mechanism by which S.suis 2 MVs participate in endothelial cell pyroptosis.In this study,we used proteomics,electron scanning microscopy,fluorescence microscope,Western blotting,and bioassays,to investigate the MVs secreted by S.suis 2.First,we demonstrated that S.suis 2 secreted MVs with an average diameter of 72.04 nm,and 200 proteins in MVs were identified.Then,we showed that MVs were transported to cells via mainly dynamin-dependent endocytosis.The S.suis 2 MVs activated NLRP3/Caspase-1/GSDMD canonical inflammasome signaling pathway,resulting in cell pyroptosis,but it did not activate the Caspase-4/-5 pathway.More importantly,endothelial cells produce large amounts of reactive oxygen species(ROS)and lost their mitochondrial membrane potential under induction by S.suis 2 MVs.The results in this study suggest for the first time that MVs from S.suis 2 were internalized by endothelial cells via mainly dynamin-dependent endocytosis and might promote NLRP3/Caspase-1/GSDMD pathway by mitochondrial damage,which produced mtDNA and ROS under induction,leading to the pyroptosis of endothelial cells.
基金funded by the National Key Research and Development Program of China(grant number:2022YFC2106300).
文摘Biobutanol is an advanced biofuel that can be produced from excess lignocellulose via acetone-butanol-ethanol(ABE)fermentation.Although significant technological progress has been made in this field,attempts at largescale lignocellulosic ABE production remain scarce.In this study,1m^(3)scale ABE fermentation was investigated using high inhibitor tolerance Clostridium acetobutylicum ABE-P1201 and steam-exploded corn stover hydrolysate(SECSH).Before expanding the fermentation scale,the detoxification process for SECSH was simplified by process engineering.Results revealed that appropriate pH management during the fed-batch cultivation could largely decrease the inhibition of the toxic components in undetoxified SECSH to the solventogenesis phase of the ABE-P1201 strains,avoiding“acid crash”.Therefore,after naturalizing the pH by Ca(OH)_(2),the undetoxified SECSH,without removal of the solid components,reached 17.68±1.30 g/L of ABE production with 0.34±0.01 g/g of yield in 1 L scale bioreactor.Based on this strategy,the fermentation scale gradually expanded from laboratory-scale apparatus to pilot-scale bioreactors.Finally,17.05±1.20 g/L of ABE titer and 0.32±0.01 g/g of ABE yield were realized in 1m3 bioreactor,corresponding to approximately 145 kg of ABE production from 1 t of dry corn stover.The pilot-scale ABE fermentation demonstrated excellent stability during repeated operations.This study provided a simplified ABE fermentation strategy and verified the feasibility of the pilot process,providing tremendous significance and a solid foundation for the future industrialization of second-generation ABE plants.
基金supported by the Cooperation Project between Chongqing Local Universities and Institutions of Chinese Academy of Sciences,Chongqing Municipal Education Commission(No.HZ2021007)the National Natural Science Foundation of China(Nos.61904024,61975003,61790584,and 62025506)the Science and Technology Research Program of Chongqing Municipal Education Commission(No.KJZD-M201900502)。
文摘The high peak power of picosecond pulses produced by a self-mode-locked semiconductor disk laser can effectively improve the efficiency of nonlinear frequency conversion.This paper presents the intracavity frequency tripling in a self-mode-locked semiconductor disk laser,and a picosecond pulse train at 327 nm wavelength is achieved.The pulse repetition rate is 0.49 GHz,and the pulse width is 5.0 ps.The obtained maximum ultraviolet output power under mode locking is 30.5 m W,and the corresponding conversion efficiency is obviously larger than that of continuous-wave operation.These ultraviolet picosecond pulses have high spatial and temporal resolution and can be applied in some emerging fields.
基金supported by the National Natural Science Foundation of China(21801104,21871121,21431002)the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(2018QNRC001)+3 种基金the Fundamental Research Funds for the Central Universities of China(lzujbky-2019-sp01,lzujbky-2019-kb12)the Special Fund Project of Guiding Scientific and Technological Innovation Development of Gansu Province(2019ZX-04)support by the US Department of Energy(DE-FG02-07ER46427)support of Gansu Computing Center of China。
文摘Inhibiting the irreversible escape of organic cations and iodide species in perovskite films is crucial for the fabrication of efficient and stable perovskite solar cells(PSCs).Here,we develop a reaction-and-assembly approach using monoamine zinc porphyrin(ZnP)to modify methylammonium(MA^+)lead iodide perovskite film.The amine group in ZnP reacts with MA^+and I^-ions to yield monoammonium zinc porphyrin(ZnP-H+I-).The resultant films show no escape of iodide when immersed in ether solutions.Measurements from space-charge limited currents and transient photoluminescence indicate the modified films have reduced density of defects.These results suggest the formed ZnP-H^+I^-is bound on the surface and grain boundary of perovskite film to retard migrations of ions.DFT calculations also show that the energy alignment between ZnP-H^+and perovskite facilitates the electron transfer and reduces charge recombination at the perovskite grains.Furthermore,post-treating the Zn Pdoped film with ZnP again results in the formation of a one dimension zig-zag coordination polymer on the surface of the perovskite film.The single crystal structure of ZnP shows the polymer layer is formed through the coordination interaction between the Zn(II)metal center and a neighboring monoamine.The polymer facilitates the interfacial charge transfer,and reduces the escape of organic cations and iodide species in perovskite films,thereby keeping the excellent cell performance(20.0%)and further realizing the ion encapsulation.Finally,the modified PSCs retain over 90%of its original efficiency over2,000 h at 85°C or AM 1.5 G continuous illumination,or over 6,000 h in 45%humidity without encapsulation.This work affords a new strategy to achieve the efficient ions immobilization and encapsulation by in situ reaction and coordination assembly of mono-amine zinc porphyrin.
基金the National Natural Science Foundation of China(21801104 and 21871121)the Fundamental Research Funds for the Central Universities of China(lzujbky-2019-sp01 and lzujbky-2018-ot01)the Special Fund Project of Guiding Scientific and Technological Innovation Development of Gansu Province(2019ZX-04)。
文摘The preparation of suitable hole transport material(HTM)is critical to the performance and stability of perovskite solar cells(PSCs)with low-cost.Herein,a mass producible and soluble copper phthalocyanine decorated with butoxy donor groups(CuPcOBu)was designed as HTM and prepared by a facile two-step synthetic route.To generate high quality HTM film,4-tertbutylpyridine(tBP)was doped into CuPc-OBu to prepare the film and then removed by annealing.Such a t BP-assisted strategy resulted in the best efficiency of the PSCs with lead trihalide perovskite up to 19.0%(small-area of 0.1 cm^2)and 10.1%(the active area of 8.0 cm^2 for the module device).And the best efficiency of the tin-based PSCs with CuPc-OBu reached to 6.9%.More importantly,the device with CuPc-OBu as HTM revealed the remarkably enhanced stability.This work provides a new strategy to improve the film-quality of free-doping HTMs and enhance the efficiency and stability of Pb-and Sn-based PSCs with low-cost.
