This study examines the effectiveness of adaptive observation experiments using the ensemble transformation sensitivity(ETS) method to improve precipitation forecasts during heavy rainfall events in South China and th...This study examines the effectiveness of adaptive observation experiments using the ensemble transformation sensitivity(ETS) method to improve precipitation forecasts during heavy rainfall events in South China and the Sichuan Basin. High-resolution numerical models are employed to simulate adaptive observations. By identifying the sensitive areas of key weather system positions 42 hours before heavy rainfall events, the adaptive observations improve the prediction of jet streams, strong winds, and shear lines, which are essential for accurate heavy rainfall forecasting. This improvement is reflected in both the precipitation structure and location accuracy within the verification region. In South China, targeted observations enhance rainfall predictions by improving water vapor transport. In the Sichuan Basin, adaptive observations refine water vapor transport and adjust vortex dynamics. This research highlights the importance of accurately predicting shear lines and jet streams for forecasting heavy rainfall in these areas. Overall, this study found that adaptive observation enhances the precipitation forecast skills of the structure and location for heavy rainfall in South China and the Sichuan Basin, emphasizing their potential utility in operational numerical weather prediction.展开更多
Background:Sepsis is a systemic inflammatory syndrome induced by several infectious agents.Multiple organs are affected by sepsis,including the liver,which plays an important role in metabolism and immune homeostasis....Background:Sepsis is a systemic inflammatory syndrome induced by several infectious agents.Multiple organs are affected by sepsis,including the liver,which plays an important role in metabolism and immune homeostasis.Fibroblast growth factors(FGFs)participate in several biological processes,although the role of FGF5 in sepsis is unclear.Methods:In this study,lipopolysaccharide(LPS)was administrated to mice to establish a sepsis-induced liver injury.A similar in vitro study was conducted using L-02 hepatocytes.Western blot and immunohistochemistry staining were performed to evaluate the FGF5 expression level in liver tissues and cells.Inflammatory cell infiltrations,cleaved-caspase-3 expressions,reactive oxygen species and levels of inflammatory cytokines were detected by immunofluorescence,dihydroethidium staining,and reverse transcription quantitative polymerase chain reaction analysis,respectively.Flow cytometry was used to detect the apoptosis level of cells.In addition,ribonucleic acid(RNA)-sequencing was applied to explore the possible mechanism by which FGF5 exerted effects.Results:LPS administration caused FGF5 down-regulation in the mouse liver as well as in L-02 hepatocytes.Additionally,with FGF5 overexpression,liver injury and the level of hepatocyte apoptosis were ameliorated.Further,RNA sequencing performed in hepatocytes revealed the phosphoinositide-3-kinase/protein kinase B(PI3K/AKT)pathway as a possible pathway regulated by FGF5.This was supported using an inhibitor of the PI3K/AKT pathway,which abrogated the protective effect of FGF5 in LPSinduced hepatocyte injury.Conclusion:The anti-apoptotic effect of FGF5 on hepatocytes suffering from LPS has been demonstrated and was dependent on the activation of the PI3K/AKT signaling pathway.展开更多
In this study,we demonstrate the axiotaxy driven growth of belt-shaped InAs nanowires using Au catalysts by molecular beam epitaxy.It is found that,the zinc-blende structured InAs nanowires,with the features of[113]gr...In this study,we demonstrate the axiotaxy driven growth of belt-shaped InAs nanowires using Au catalysts by molecular beam epitaxy.It is found that,the zinc-blende structured InAs nanowires,with the features of[113]growth direction and extensive{110}side-surfaces,are induced by catalysts in Au–In α phase through the axiotaxy growth,in which the lattice mismatch between the projections of atomic planes onto nanowire/catalyst interfaces is minimized by forming extraordinary tilted interfaces.Our atomic-resolution in situ TEM heating experiments show that the catalysts remained in the solid state of Au–In α phase during the axiotaxy growth,by which the vapor–solid–solid growth mechanism can be confirmed.Through manipulating the growth direction,this unusual growth mechanism can provide a practical pathway to control the morphology of the low-dimensional nanomaterials,from conventional nanowires to belt-shaped nanowires utilizing a significant lateral growth,simply using nanoparticles as catalyst.展开更多
Semiconductor nanowires(NWs)could simultaneously provide gain medium and optical cavity for performing nanoscale lasers with easy integration,ultracompact footprint,and low energy consumption.Here,we report Ⅲ-Ⅴsemic...Semiconductor nanowires(NWs)could simultaneously provide gain medium and optical cavity for performing nanoscale lasers with easy integration,ultracompact footprint,and low energy consumption.Here,we report Ⅲ-Ⅴsemiconductor NW lasers can also be used for self-frequency conversion to extend their output wavelengths,as a result of their non-centrosymmetric crystal structure and strongly localized optical field in the NWs.From a GaAs/In0.16Ga0.84As core/shell NW lasing at 1016 nm,an extra visible laser output at 508 nm is obtained via the process of second-harmonic generation,as confirmed by the far-field polarization dependence measurements and numerical modeling.From another NW laser with a larger diameter which supports multiple fundamental lasing wavelengths,multiple self-frequency-conversion lasing modes are observed due to second-harmonic generation and sum-frequency generation.The demonstrated self-frequency conversion of NW lasers opens an avenue for extending the working wavelengths of nanoscale lasers,even to the deep ultraviolet and THz range.展开更多
We report an indium phosphide nanowire(NW)-induced cavity in a silicon planar photonic crystal(PPC)waveguide to improve the light–NW coupling.The integration of NW shifts the transmission band of the PPC waveguide in...We report an indium phosphide nanowire(NW)-induced cavity in a silicon planar photonic crystal(PPC)waveguide to improve the light–NW coupling.The integration of NW shifts the transmission band of the PPC waveguide into the mode gap of the bare waveguide,which gives rise to a microcavity located on the NW section.Resonant modes with𝑄factors exceeding 103 are obtained.Leveraging on the high density of the electric field in the microcavity,the light–NW interaction is enhanced strongly for efficient nonlinear frequency conversion.Second-harmonic generation and sum-frequency generation in the NW are realized with a continuous-wave pump laser in a power level of tens of microwatts,showing a cavity-enhancement factor of 112.The hybrid integration structure of NW-PPC waveguide and the self-formed microcavity not only opens a simple strategy to effectively enhance light–NW interactions,but also provides a compact platform to construct NW-based on-chip active devices.展开更多
基金jointly supported by the Guangdong Province University Student Innovation and Entrepreneurship Project (580520049)the Guangdong Ocean University Scientific Research Startup Fund (R20021)the Key Laboratory of Plateau and Basin Rainstorm and Drought Disasters in Sichuan Province Open Research Fund (SZKT201902)。
文摘This study examines the effectiveness of adaptive observation experiments using the ensemble transformation sensitivity(ETS) method to improve precipitation forecasts during heavy rainfall events in South China and the Sichuan Basin. High-resolution numerical models are employed to simulate adaptive observations. By identifying the sensitive areas of key weather system positions 42 hours before heavy rainfall events, the adaptive observations improve the prediction of jet streams, strong winds, and shear lines, which are essential for accurate heavy rainfall forecasting. This improvement is reflected in both the precipitation structure and location accuracy within the verification region. In South China, targeted observations enhance rainfall predictions by improving water vapor transport. In the Sichuan Basin, adaptive observations refine water vapor transport and adjust vortex dynamics. This research highlights the importance of accurately predicting shear lines and jet streams for forecasting heavy rainfall in these areas. Overall, this study found that adaptive observation enhances the precipitation forecast skills of the structure and location for heavy rainfall in South China and the Sichuan Basin, emphasizing their potential utility in operational numerical weather prediction.
基金the National Science and Technology Support Program(grant number:2015BAI08B01).
文摘Background:Sepsis is a systemic inflammatory syndrome induced by several infectious agents.Multiple organs are affected by sepsis,including the liver,which plays an important role in metabolism and immune homeostasis.Fibroblast growth factors(FGFs)participate in several biological processes,although the role of FGF5 in sepsis is unclear.Methods:In this study,lipopolysaccharide(LPS)was administrated to mice to establish a sepsis-induced liver injury.A similar in vitro study was conducted using L-02 hepatocytes.Western blot and immunohistochemistry staining were performed to evaluate the FGF5 expression level in liver tissues and cells.Inflammatory cell infiltrations,cleaved-caspase-3 expressions,reactive oxygen species and levels of inflammatory cytokines were detected by immunofluorescence,dihydroethidium staining,and reverse transcription quantitative polymerase chain reaction analysis,respectively.Flow cytometry was used to detect the apoptosis level of cells.In addition,ribonucleic acid(RNA)-sequencing was applied to explore the possible mechanism by which FGF5 exerted effects.Results:LPS administration caused FGF5 down-regulation in the mouse liver as well as in L-02 hepatocytes.Additionally,with FGF5 overexpression,liver injury and the level of hepatocyte apoptosis were ameliorated.Further,RNA sequencing performed in hepatocytes revealed the phosphoinositide-3-kinase/protein kinase B(PI3K/AKT)pathway as a possible pathway regulated by FGF5.This was supported using an inhibitor of the PI3K/AKT pathway,which abrogated the protective effect of FGF5 in LPSinduced hepatocyte injury.Conclusion:The anti-apoptotic effect of FGF5 on hepatocytes suffering from LPS has been demonstrated and was dependent on the activation of the PI3K/AKT signaling pathway.
基金This work was supported by the Australian Research Council,the National Key R&D Program of China(No.2016YFB0402401)the National Natural Science Foundation of China(Nos.11634009,11774016,and 61974138)+2 种基金the Natural Science Basic Research Program of Shaanxi Province(No.2020JQ-222)the Key Programs of Frontier Science of the Chinese Academy of Sciences(No.QYZDJ-SSW-JSC007)Dong Pan acknowledges the support from the Youth Innovation Promotion Association,the Chinese Academy of Sciences(Grant 2017156).
文摘In this study,we demonstrate the axiotaxy driven growth of belt-shaped InAs nanowires using Au catalysts by molecular beam epitaxy.It is found that,the zinc-blende structured InAs nanowires,with the features of[113]growth direction and extensive{110}side-surfaces,are induced by catalysts in Au–In α phase through the axiotaxy growth,in which the lattice mismatch between the projections of atomic planes onto nanowire/catalyst interfaces is minimized by forming extraordinary tilted interfaces.Our atomic-resolution in situ TEM heating experiments show that the catalysts remained in the solid state of Au–In α phase during the axiotaxy growth,by which the vapor–solid–solid growth mechanism can be confirmed.Through manipulating the growth direction,this unusual growth mechanism can provide a practical pathway to control the morphology of the low-dimensional nanomaterials,from conventional nanowires to belt-shaped nanowires utilizing a significant lateral growth,simply using nanoparticles as catalyst.
基金This work is supported by the National Key R&D Program of China(Grant Nos.2018YFA0307200 and 2017YFA0303800)the National Natural Science Foundation of China(Grant Nos.61775183,11634010,61905196,and 62005222)+1 种基金the Fundamental Research Funds for the Central Universities(Grant Nos.3102017jc01001,3102019JC008,and 3102019110x032)the Natural Science Basic Research Program of Shaanxi Province(2020JQ 222).
文摘Semiconductor nanowires(NWs)could simultaneously provide gain medium and optical cavity for performing nanoscale lasers with easy integration,ultracompact footprint,and low energy consumption.Here,we report Ⅲ-Ⅴsemiconductor NW lasers can also be used for self-frequency conversion to extend their output wavelengths,as a result of their non-centrosymmetric crystal structure and strongly localized optical field in the NWs.From a GaAs/In0.16Ga0.84As core/shell NW lasing at 1016 nm,an extra visible laser output at 508 nm is obtained via the process of second-harmonic generation,as confirmed by the far-field polarization dependence measurements and numerical modeling.From another NW laser with a larger diameter which supports multiple fundamental lasing wavelengths,multiple self-frequency-conversion lasing modes are observed due to second-harmonic generation and sum-frequency generation.The demonstrated self-frequency conversion of NW lasers opens an avenue for extending the working wavelengths of nanoscale lasers,even to the deep ultraviolet and THz range.
基金Key Research and Development Program(2017YFA0303800)National Natural Science Foundation of China(11634010,61775183,61905196,91950119)+5 种基金Key Research and Development Program in Shaanxi Province of China(2017KJXX-12,2018JM1058)Fundamental Research Funds for the Central Universities(310201911cx032,3102019JC008)Aalto University Doctoral School,Walter Ahlstrom Foundation,Nokia Foundation,Academy of Finland(298297)Academy of Finland Flagship Program(320167,PREIN)Horizon 2020 Framework Programme(820423)European Research Council(834742).
文摘We report an indium phosphide nanowire(NW)-induced cavity in a silicon planar photonic crystal(PPC)waveguide to improve the light–NW coupling.The integration of NW shifts the transmission band of the PPC waveguide into the mode gap of the bare waveguide,which gives rise to a microcavity located on the NW section.Resonant modes with𝑄factors exceeding 103 are obtained.Leveraging on the high density of the electric field in the microcavity,the light–NW interaction is enhanced strongly for efficient nonlinear frequency conversion.Second-harmonic generation and sum-frequency generation in the NW are realized with a continuous-wave pump laser in a power level of tens of microwatts,showing a cavity-enhancement factor of 112.The hybrid integration structure of NW-PPC waveguide and the self-formed microcavity not only opens a simple strategy to effectively enhance light–NW interactions,but also provides a compact platform to construct NW-based on-chip active devices.