目的探讨急性胰腺炎(acute pancreatitis,AP)患者血清高迁移率族蛋白B1(high mobility group protein B1,HMGB1)和一氧化氮(nitric oxide,NO)的表达对AP患病及严重程度的评估价值,并分析两者的相关性。方法收集AP病例70例,其中轻症急性...目的探讨急性胰腺炎(acute pancreatitis,AP)患者血清高迁移率族蛋白B1(high mobility group protein B1,HMGB1)和一氧化氮(nitric oxide,NO)的表达对AP患病及严重程度的评估价值,并分析两者的相关性。方法收集AP病例70例,其中轻症急性胰腺炎(mild acute pancreatitis,MAP)组27例,中度重症急性胰腺炎(moderately severe acute pancreatitis,MSAP)组21例,重症急性胰腺炎(severe acute pancreatitis,SAP)组22例,以32例同期健康体检者作为对照组。采用ELISA检测各组血清HMGB1表达水平,分光光度法检测NO表达水平,通过ROC曲线探究HMGB1和NO对评估AP严重程度及患病的敏感性及特异性,并分析各组HMGB1水平与NO浓度之间的相关性。结果各组的一般资料比较,差异无统计学意义(P>0.05)。MAP组、MSAP组、SAP组患者血清中HMGB1、NO水平均显著高于对照组(P<0.01);MSAP组的NO水平高于MAP组(P<0.001),而HMGB1水平差异无统计学意义(P>0.05);SAP组的HMGB1、NO水平高于MAP及MSAP组(P<0.05)。SAP组中HMGB1与NO水平呈正相关(r s=0.672,P<0.001)。AP严重程度越高,HMGB1和NO水平越高,对评估AP严重程度及患病的敏感性及特异性增加。结论血清HMGB1及NO的表达水平对判断AP患病及严重程度有一定的评估价值;在SAP中,HMGB1和NO的表达水平具有相关性,其可能通过促进NO产生增多,共同参与SAP的发生发展。展开更多
As a natural biaxial hyperbolic material, α-phase molybdenum trioxide(α-MoO_(3)) exhibits dielectric and metallic properties in the plane, rendering it an exceptional candidate for polarization-dependent devices. In...As a natural biaxial hyperbolic material, α-phase molybdenum trioxide(α-MoO_(3)) exhibits dielectric and metallic properties in the plane, rendering it an exceptional candidate for polarization-dependent devices. In this work, we design a lithography-free polarization-dependent absorber consisting of an α-MoO_(3)film, a germanium layer, and a silver substrate. The results show that a narrowband absorption of up to 0.99 is achieved at a wavelength of 12.2 μm for transverse magnetic polarization. In contrast, the absorption is only 0.06 at this wavelength for transverse electric polarization. This remarkable polarization-dependent absorption performance is attributed to the coupling of epsilon-near-zero modes and Fabry-Perot resonances, which is confirmed by the electric field and power dissipation density distributions. Furthermore, strong polarization-dependent performance could also be achieved when the crystal axis of α-MoO_(3)is rotated in the out-of-plane. This work demonstrates that in-plane anisotropic α-MoO_(3)has the potential for designing high polarization-dependent devices.展开更多
Proposed in the paper is a trigonometric interpolation method for efficient determination of turbomachinery blade aero-damping curves which are required in a flutter assessment.The trigonometric interpolation method w...Proposed in the paper is a trigonometric interpolation method for efficient determination of turbomachinery blade aero-damping curves which are required in a flutter assessment.The trigonometric interpolation method was proposed to be incorporated with the widely used travelling wave method to replace the influence coefficient method.Through analyzing aero-damping/worksum at a few carefully chosen nodal diameters,trigonometric interpolation was applied through existing data points to get aero-damping/worksum at the rest nodal diameters.The proposed approach is much more efficient than the travelling wave method for determining the aero-damping curve of a blade.In principle,the method can be as efficient as the influence coefficient method.Unlike the influence coefficient method,the trigonometric interpolation method does not involve linear superposition,and it can include nonlinear effect and is expected to be more accurate.Two test cases were provided to validate the proposed method and demonstrate its effectiveness.The method is not only effective,but also very easy to be incorporated into existing widely used aero-damping/worksum analysis system using the travelling wave method.展开更多
Since the transition from rotating stall to surge in a transonic compressor at high speed is very quick,quite often there is no time to take measures to prevent the surge.Therefore,it is desired to find any rotating s...Since the transition from rotating stall to surge in a transonic compressor at high speed is very quick,quite often there is no time to take measures to prevent the surge.Therefore,it is desired to find any rotating stall precursors,of which the occurrence can offer sufficient time for stall or surge prevention.In this study,a series of unsteady flow analyses were performed on a transonic compressor under operating conditions before rotating stall with unsteady results scrutinized to find rotating stall precursors.Particular attention is paid to the spatial modes and time modes of static pressure near the casing and around the blade leading and trailing edges.The results show that the characteristics of the precursor in both spatial and time domains can be used as rotating stall warnings.展开更多
文摘目的探讨急性胰腺炎(acute pancreatitis,AP)患者血清高迁移率族蛋白B1(high mobility group protein B1,HMGB1)和一氧化氮(nitric oxide,NO)的表达对AP患病及严重程度的评估价值,并分析两者的相关性。方法收集AP病例70例,其中轻症急性胰腺炎(mild acute pancreatitis,MAP)组27例,中度重症急性胰腺炎(moderately severe acute pancreatitis,MSAP)组21例,重症急性胰腺炎(severe acute pancreatitis,SAP)组22例,以32例同期健康体检者作为对照组。采用ELISA检测各组血清HMGB1表达水平,分光光度法检测NO表达水平,通过ROC曲线探究HMGB1和NO对评估AP严重程度及患病的敏感性及特异性,并分析各组HMGB1水平与NO浓度之间的相关性。结果各组的一般资料比较,差异无统计学意义(P>0.05)。MAP组、MSAP组、SAP组患者血清中HMGB1、NO水平均显著高于对照组(P<0.01);MSAP组的NO水平高于MAP组(P<0.001),而HMGB1水平差异无统计学意义(P>0.05);SAP组的HMGB1、NO水平高于MAP及MSAP组(P<0.05)。SAP组中HMGB1与NO水平呈正相关(r s=0.672,P<0.001)。AP严重程度越高,HMGB1和NO水平越高,对评估AP严重程度及患病的敏感性及特异性增加。结论血清HMGB1及NO的表达水平对判断AP患病及严重程度有一定的评估价值;在SAP中,HMGB1和NO的表达水平具有相关性,其可能通过促进NO产生增多,共同参与SAP的发生发展。
基金supported by the National Natural Science Foundation of China (Grant No. 52106099)Shandong Provincial Natural Science Foundation (Grant No. ZR2022YQ57)+1 种基金Taishan Scholars ProgramBasic and Applied Basic Research Fund Project of Guangdong Province (Grant No. 2019A1515111178)。
文摘As a natural biaxial hyperbolic material, α-phase molybdenum trioxide(α-MoO_(3)) exhibits dielectric and metallic properties in the plane, rendering it an exceptional candidate for polarization-dependent devices. In this work, we design a lithography-free polarization-dependent absorber consisting of an α-MoO_(3)film, a germanium layer, and a silver substrate. The results show that a narrowband absorption of up to 0.99 is achieved at a wavelength of 12.2 μm for transverse magnetic polarization. In contrast, the absorption is only 0.06 at this wavelength for transverse electric polarization. This remarkable polarization-dependent absorption performance is attributed to the coupling of epsilon-near-zero modes and Fabry-Perot resonances, which is confirmed by the electric field and power dissipation density distributions. Furthermore, strong polarization-dependent performance could also be achieved when the crystal axis of α-MoO_(3)is rotated in the out-of-plane. This work demonstrates that in-plane anisotropic α-MoO_(3)has the potential for designing high polarization-dependent devices.
基金supported by China’s 111 project(Grant No.B17037)National Natural Science Foundation of China(Grant No.51976172)National Science and Technology Major Project(2017-II-0009-0023)。
文摘Proposed in the paper is a trigonometric interpolation method for efficient determination of turbomachinery blade aero-damping curves which are required in a flutter assessment.The trigonometric interpolation method was proposed to be incorporated with the widely used travelling wave method to replace the influence coefficient method.Through analyzing aero-damping/worksum at a few carefully chosen nodal diameters,trigonometric interpolation was applied through existing data points to get aero-damping/worksum at the rest nodal diameters.The proposed approach is much more efficient than the travelling wave method for determining the aero-damping curve of a blade.In principle,the method can be as efficient as the influence coefficient method.Unlike the influence coefficient method,the trigonometric interpolation method does not involve linear superposition,and it can include nonlinear effect and is expected to be more accurate.Two test cases were provided to validate the proposed method and demonstrate its effectiveness.The method is not only effective,but also very easy to be incorporated into existing widely used aero-damping/worksum analysis system using the travelling wave method.
基金The research was supported by the National Natural Science Foundation of China under Grant No.51976172,National Science and Technology Major Project(2017-II-O009-0023),and China's 111 project under Grant No.B17037.
文摘Since the transition from rotating stall to surge in a transonic compressor at high speed is very quick,quite often there is no time to take measures to prevent the surge.Therefore,it is desired to find any rotating stall precursors,of which the occurrence can offer sufficient time for stall or surge prevention.In this study,a series of unsteady flow analyses were performed on a transonic compressor under operating conditions before rotating stall with unsteady results scrutinized to find rotating stall precursors.Particular attention is paid to the spatial modes and time modes of static pressure near the casing and around the blade leading and trailing edges.The results show that the characteristics of the precursor in both spatial and time domains can be used as rotating stall warnings.
