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Microwave electrometry with Rydberg atoms in a vapor cell using microwave amplitude modulation
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作者 郝建海 贾凤东 +9 位作者 崔越 王昱寒 周飞 刘修彬 张剑 谢锋 白金海 尤建琦 王宇 钟志萍 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期65-74,共10页
We have theoretically and experimentally studied the dispersive signal of the Rydberg atomic electromagneticallyinduced transparency(EIT)Autler–Townes(AT)splitting spectra obtained using amplitude modulation of the m... We have theoretically and experimentally studied the dispersive signal of the Rydberg atomic electromagneticallyinduced transparency(EIT)Autler–Townes(AT)splitting spectra obtained using amplitude modulation of the microwave(MW)electric field.In addition to the two zero-crossing points interval△f_(zeros),the dispersion signal has two positive maxima with an interval defined as the shoulder interval△f_(sho),which is theoretically expected to be used to measure a much weaker MW electric field.The relationship of the MW field strength E_(MW)and△f_(sho)is experimentally studied at the MW frequencies of 31.6 GHz and 9.2 GHz respectively.The results show that△f_(sho)can be used to characterize the much weaker E_(MW)than that of△f_(zeros)and the traditional EIT–AT splitting interval△f_(m);the minimum E_(MW)measured by△f_(sho)is about 30 times smaller than that by△f_(m).As an example,the minimum E_(MW)at 9.2 GHz that can be characterized by△f_(sho)is 0.056 mV/cm,which is the minimum value characterized by the frequency interval using a vapor cell without adding any auxiliary fields.The proposed method can improve the weak limit and sensitivity of E_(MW)measured by the spectral frequency interval,which is important in the direct measurement of weak E_(MW). 展开更多
关键词 quantum sensor Rydberg atoms electromagnetically induced transparency amplitude modulation
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The Impact of Model Based Offset Scaling Technique on the Amplitude Variation with Offset Responses from 3D Seismic Data Acquired from the Tano Basin, Offshore Ghana
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作者 Striggner Bedu-Addo Sylvester Kojo Danuor Aboagye Menyeh 《International Journal of Geosciences》 CAS 2024年第1期40-53,共14页
Amplitudes have been found to be a function of incident angle and offset. Hence data required to test for amplitude variation with angle or offset needs to have its amplitudes for all offsets preserved and not stacked... Amplitudes have been found to be a function of incident angle and offset. Hence data required to test for amplitude variation with angle or offset needs to have its amplitudes for all offsets preserved and not stacked. Amplitude Variation with Offset (AVO)/Amplitude Variation with Angle (AVA) is necessary to account for information in the offset/angle parameter (mode converted S-wave and P-wave velocities). Since amplitudes are a function of the converted S- and P-waves, it is important to investigate the dependence of amplitudes on the elastic (P- and S-waves) parameters from the seismic data. By modelling these effects for different reservoir fluids via fluid substitution, various AVO geobody classes present along the well and in the entire seismic cube can be observed. AVO analysis was performed on one test well (Well_1) and 3D pre-stack angle gathers from the Tano Basin. The analysis involves creating a synthetic model to infer the effect of offset scaling techniques on amplitude responses in the Tano basin as compared to the effect of unscaled seismic data. The spectral balance process was performed to match the amplitude spectra of all angle stacks to that of the mid (26°) stack on the test lines. The process had an effect primarily on the far (34° - 40°) stacks. The frequency content of these stacks slightly increased to match that of the near and mid stacks. In offset scaling process, the root mean square (RMS) amplitude comparison between the synthetic and seismic suggests that the amplitude of the far traces should be reduced relative to the nears by up to 16%. However, the exact scaler values depend on the time window considered. This suggests that the amplitude scaling with offset delivered from seismic processing is only approximately correct and needs to be checked with well synthetics and adjusted accordingly prior to use for AVO studies. The AVO attribute volumes generated were better at resolving anomalies on spectrally balanced and offset scaled data than data delivered from conventional processing. A typical class II AVO anomaly is seen along the test well from the cross-plot analysis and AVO attribute cube which indicates an oil filled reservoir. 展开更多
关键词 amplitude Variation with Offset (AVO) Model Based Offset Scaling Technique Tano Basin
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O(logN) Algorithm for Amplitude Amplification and O(logN) Algorithms for Amplitude Transfer in Grover’s Algorithm
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作者 Ying Liu 《American Journal of Computational Mathematics》 2024年第2期169-188,共20页
Grovers algorithm is a category of quantum algorithms that can be applied to many problems through the exploitation of quantum parallelism. The Amplitude Amplification in Grovers algorithm is T = O(N). This paper intr... Grovers algorithm is a category of quantum algorithms that can be applied to many problems through the exploitation of quantum parallelism. The Amplitude Amplification in Grovers algorithm is T = O(N). This paper introduces two new algorithms for Amplitude Amplification in Grovers algorithm with a time complexity of T = O(logN), aiming to improve efficiency in quantum computing. The difference between Grovers algorithm and our first algorithm is that the Amplitude Amplification ratio in Grovers algorithm is an arithmetic series and ours, a geometric one. Because our Amplitude Amplification ratios converge much faster, the time complexity is improved significantly. In our second algorithm, we introduced a new concept, Amplitude Transfer where the marked state is transferred to a new set of qubits such that the new qubit state is an eigenstate of measurable variables. When the new qubit quantum state is measured, with high probability, the correct solution will be obtained. 展开更多
关键词 Quantum Computing ORACLE amplitude amplification Grover’s Algorithm
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Atlantic blocking events in a simplified nonlinear baroclinic model for local finite-amplitude wave activity
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作者 Ning Shi Bamidele Abiodun Paul Wencai Liu 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第4期41-45,共5页
为研究北大西洋阻高的形成机制,本文在局部有限振幅波活动(LWA)框架下进行了一系列数值实验.采用的数值模型能显式地描绘出两种重要的大气内部动力过程,即非线性纬向位涡通量和Rossby波包传播.模拟结果显示,这两种动力学过程均是形成大... 为研究北大西洋阻高的形成机制,本文在局部有限振幅波活动(LWA)框架下进行了一系列数值实验.采用的数值模型能显式地描绘出两种重要的大气内部动力过程,即非线性纬向位涡通量和Rossby波包传播.模拟结果显示,这两种动力学过程均是形成大西洋阻高的重要机理.具体地,非线性纬向位涡通量和Rossby波包传播,分别是大西洋阻高南部和北部LWA形成的主导因子.因此,本研究综合了前人关于大西洋阻高的研究成果,为其形成机理提供了新的认识. 展开更多
关键词 斜压模式 局地有限振幅波活动 罗斯贝波传播 非线性效应
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Trend in seasonal amplitude of northern net ecosystem production:Simulated results from IAP DGVM in CAS-ESM2
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作者 Jiawen Zhu Xiaodong Zeng 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第2期45-51,共7页
北方陆地净生态系统生产力(NEP)具有明显的季节变化特征,这是大气CO_(2)季节变化的关键驱动.研究这些碳循环过程并理解潜在的驱动因素是气候研究的一个关键问题.本文利用第二代中国科学院地球系统模式(CAS-ESM2)中的全球植被动态模型(IA... 北方陆地净生态系统生产力(NEP)具有明显的季节变化特征,这是大气CO_(2)季节变化的关键驱动.研究这些碳循环过程并理解潜在的驱动因素是气候研究的一个关键问题.本文利用第二代中国科学院地球系统模式(CAS-ESM2)中的全球植被动态模型(IAPDGVM),研究了1990-2014年北方NEP(40°-90°N)的季节振幅及其变化趋势.在初始化试验的基础上,本文开展了一个控制试验来评估模拟的北方NEP季节幅度的变化趋势,同时开展了三个敏感性试验来研究气候和大气CO_(2)的贡献.结果表明:1990-2014年,模拟的北方NEP季节振幅显著增加,趋势为9.69万吨碳/月/年,这主要是由于最大NEP增加所致.当分别排除CO_(2)施肥效应和气候效应时,上述增加趋势大大减弱.这些显著的减少表明大气CO_(2)和气候变化对北方NEP的季节性振幅有重要影响.尽管模式存在不确定性,但这些结果有利于进一步提升IAPDGVM对陆地碳循环的精确模拟,也为CAS-ESM研究碳-气候相互作用的应用提供了重要参考. 展开更多
关键词 净生态系统生产力 北方陆地生态系统 季节变化幅度 CO_(2)施肥效应 气候效应
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Lensless complex amplitude demodulation based on deep learning in holographic data storage 被引量:2
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作者 Jianying Hao Xiao Lin +5 位作者 Yongkun Lin Mingyong Chen Ruixian Chen Guohai Situ Hideyoshi Horimai Xiaodi Tan 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第3期42-56,共15页
To increase the storage capacity in holographic data storage(HDS),the information to be stored is encoded into a complex amplitude.Fast and accurate retrieval of amplitude and phase from the reconstructed beam is nece... To increase the storage capacity in holographic data storage(HDS),the information to be stored is encoded into a complex amplitude.Fast and accurate retrieval of amplitude and phase from the reconstructed beam is necessary during data readout in HDS.In this study,we proposed a complex amplitude demodulation method based on deep learning from a single-shot diffraction intensity image and verified it by a non-interferometric lensless experiment demodulating four-level amplitude and four-level phase.By analyzing the correlation between the diffraction intensity features and the amplitude and phase encoding data pages,the inverse problem was decomposed into two backward operators denoted by two convolutional neural networks(CNNs)to demodulate amplitude and phase respectively.The experimental system is simple,stable,and robust,and it only needs a single diffraction image to realize the direct demodulation of both amplitude and phase.To our investigation,this is the first time in HDS that multilevel complex amplitude demodulation is achieved experimentally from one diffraction intensity image without iterations. 展开更多
关键词 holographic data storage complex amplitude demodulation deep learning computational imaging
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An Example of a Bounded Potential q(x) on the Half-Line, for Estimates of A(α) Amplitude
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作者 Herminio Blancarte 《Applied Mathematics》 2023年第2期130-149,共20页
We show an example of a bounded potential on the half-line obtained as the image of an Inverse Transformation Operator of the Bessel singular potential of the Reduced Radial Schr&#246;dinger Equation, and show us ... We show an example of a bounded potential on the half-line obtained as the image of an Inverse Transformation Operator of the Bessel singular potential of the Reduced Radial Schr&#246;dinger Equation, and show us the Estimates of the A(α) amplitude. 展开更多
关键词 The amplitude A(α) as a Function of the Phase α Estimates of the A(α) amplitude A Bounded Potential on the Half Line
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Physical-mechanical properties of sediments and their correlation with near seafloor seismic amplitude in the Liwan canyon area, northern South China Sea
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作者 Jie Liu Lejun Liu Ping Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第5期130-138,共9页
Before the implementation of offshore oil and gas exploitation,it is essential to understand the various factors that influence the stability of submarine sediments surrounding the project.Considering the factors such... Before the implementation of offshore oil and gas exploitation,it is essential to understand the various factors that influence the stability of submarine sediments surrounding the project.Considering the factors such as cost and operability,it is not feasible to assess the physical-mechanical properties of sediments covering the entire region by borehole sampling.In this study,the correlation between near seafloor seismic amplitude and the mean shear strength of shallow sediments was explored using seismic and core testing data from the northern continental slope area of the South China Sea.Results showed that the mean water content of sediments in the layer up to 12 m below the seafloor(mbsf)gradually increased with increasing water depth,and the mean shear strength tended to decrease rapidly near the 1000 m depth contour.The near seafloor seismic amplitude could reflect the mean shear strength of sediments in the 12 mbsf layer under seismic frequency of 65 Hz and wave velocity of 1600 m/s.When the mean shear strength was greater than 10 kPa or the water depth was less than 1000 m,there was a significant linear positive correlation between mean shear strength and near seafloor seismic amplitude.Otherwise,there was a significant linear negative correlation between mean shear strength and near seafloor seismic amplitude.On the basis of these correlations,the pattern of shear strength was estimated from near seafloor seismic amplitude and mapped.The mean shear strength of sediments above 12 mbsf gradually decreased with increasing water depth in the continental slope area,whereas little change occurred in the continental shelf and the end of the canyon.Within the canyon area,the mean shear strength of sediments was characterized by larger values in both sides of the canyon walls and smaller values in the canyon bottom,which was consistent with the infinite slope stability theory.The study provides a method for using near seafloor seismic amplitude data to guide sediment sampling design,and presents a continuous dataset of sediment strength for the simulation of regional sediment stability. 展开更多
关键词 shear strength near seafloor seismic amplitude correlation and estimation northern South China Sea
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Application of the extended Fourier amplitude sensitivity testing(FAST)method to inflated,axial stretched,and residually stressed cylinders
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作者 H.ASGHARI H.TOPOL +1 位作者 B.MARKERT J.MERODIO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第12期2139-2162,共24页
This paper is dedicated to applying the Fourier amplitude sensitivity test(FAST)method to the problem of mixed extension and inflation of a circular cylindrical tube in the presence of residual stresses.The metafuncti... This paper is dedicated to applying the Fourier amplitude sensitivity test(FAST)method to the problem of mixed extension and inflation of a circular cylindrical tube in the presence of residual stresses.The metafunctions and the Ishigami function are considered in the sensitivity analysis(SA).The effects of the input variables on the output variables are investigated,and the most important parameters of the system under the applied pressure and axial force such as the axial stretch and the azimuthal stretch are determined. 展开更多
关键词 sensitivity analysis(SA) Fourier amplitude sensitivity test(FAST)method cylindrical inflation nonlinear elasticity
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Assessment of cyclic deformation and critical stress amplitude of jointed rocks via cyclic triaxial testing
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作者 Waranga Habaraduwa Peellage Behzad Fatahi Haleh Rasekh 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第6期1370-1390,共21页
Jointed rock specimens with a natural replicated joint surface oriented at a mean dip angle of 60were prepared,and a series of cyclic triaxial tests was performed at different confining pressures and cyclic deviatoric... Jointed rock specimens with a natural replicated joint surface oriented at a mean dip angle of 60were prepared,and a series of cyclic triaxial tests was performed at different confining pressures and cyclic deviatoric stress amplitudes.The samples were subjected to 10,000 loading-unloading cycles with a frequency of 8 Hz.At each level of confining pressure,the applied cyclic deviatoric stress amplitude was increased incrementally until excessive deformation of the jointed rock specimen was observed.Analysis of the test results indicated that there existed a critical cyclic deviatoric stress amplitude(i.e.critical dynamic deviatoric stress)beyond which the jointed rock specimens yielded.The measured critical dynamic deviatoric stress was less than the corresponding static deviatoric stress.At cyclic deviatoric stress amplitudes less than the critical dynamic deviatoric stress,minor cumulative residual axial strains were observed,resulting in hysteretic damping.However,for cyclic deviatoric stresses beyond the critical dynamic deviatoric stress,the plastic strains increased promptly,and the resilient moduli degraded rapidly during the initial loading cycles.Cyclic triaxial test results showed that at higher confining pressures,the ultimate residual axial strain attained by the jointed rock specimen decreased,the steadystate dissipated energy density and steady-state damping ratio per load cycle decreased,while steadystate resilient moduli increased. 展开更多
关键词 Cyclic triaxial test Jointed rock Joint surface Confining pressure Cyclic deviatoric stress amplitude FAILURE Residual deformation Dissipated energy
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人参皂苷Rc通过调控AMPK通路介导的细胞焦亡减轻小鼠脑缺血再灌注损伤
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作者 李良勇 马莉 +1 位作者 李亚军 梅灯 《中国病理生理杂志》 CAS CSCD 北大核心 2024年第5期844-851,共8页
目的:探讨人参皂苷Rc对脑缺血再灌注损伤(CIRI)小鼠的保护作用,并从细胞焦亡角度阐释其作用机制。方法:将C57BL/6小鼠随机分为假手术(sham)组、大脑中动脉闭塞/再灌注(MCAO/R)组、人参皂苷Rc+MCAO/R组(Rc组)、AMP活化蛋白激酶(AMPK)激... 目的:探讨人参皂苷Rc对脑缺血再灌注损伤(CIRI)小鼠的保护作用,并从细胞焦亡角度阐释其作用机制。方法:将C57BL/6小鼠随机分为假手术(sham)组、大脑中动脉闭塞/再灌注(MCAO/R)组、人参皂苷Rc+MCAO/R组(Rc组)、AMP活化蛋白激酶(AMPK)激动剂阿卡地新(AICAR)+MCAO/R组(agonist组)和人参皂苷Rc+MCAO/R+AMPK抑制剂Compound C组(Rc+inhibitor组)。对agonist组小鼠给予AICAR(500 mg/kg)腹腔注射,Rc+inhibitor组小鼠给予Compound C(20 mg/kg)腹腔注射;Rc组和Rc+inhibitor组小鼠造模后给予人参皂苷Rc(40 mg/kg)灌胃,每天一次,连续7 d;sham组和MCAO/R组则给予等体积的纯化水。Zea Longa评分观察小鼠神经功能缺损程度,TTC染色观察小鼠脑梗死体积,干湿重法观察小鼠脑水肿程度,HE染色观察小鼠脑组织病理形态的改变,RT-qPCR和Western blot检测小鼠脑组织AMPK、核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)、胱天蛋白酶1(caspase-1)和焦亡效应蛋白消皮素D(GSDMD)的表达,ELISA检测炎症因子白细胞介素1β(IL-1β)和IL-18的含量。结果:Rc组和agonist组小鼠神经功能缺损症状减轻,脑梗死体积减小,脑水肿和神经元病理损伤受到抑制,脑组织pAMPK/AMPK比值和AMPK mRNA表达水平升高,细胞焦亡相关蛋白NLRP3、caspase-1和GSDMD的mRNA和蛋白表达水平降低,炎症因子IL-1β和IL-18表达水平降低。Rc+inhibitor组小鼠脑组织p-AMPK/AMPK比值和AMPK mRNA表达水平较Rc组显著下降(P<0.05),NLRP3、caspase-1和GSDMD的mRNA和蛋白表达水平,以及IL-1β和IL-18表达水平显著升高(P<0.05),小鼠神经功能缺损程度评分升高,脑梗死体积增大,脑水肿和神经元病理损伤显著加重(P<0.05)。结论:人参皂苷Rc可能通过活化AMPK通路抑制NLRP3/caspase-1/GSDMD介导的细胞焦亡,从而减轻小鼠CIRI。 展开更多
关键词 人参皂苷Rc 脑缺血再灌注损伤 amp活化蛋白激酶 细胞焦亡
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基于NOD2介导的AMPK/mTOR信号通路探讨宫颈癌细胞恶性行为的机制
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作者 杜瑞亭 伍东月 +1 位作者 郭清民 靳冬梅 《安徽医科大学学报》 CAS 北大核心 2024年第2期316-324,共9页
目的 基于核苷酸结合寡聚化结构域受体2(NOD2)介导的AMP活化蛋白激酶(AMPK)/雷帕霉素靶蛋白(mTOR)信号通路探讨宫颈癌(CC)细胞恶性行为的机制。方法 生物信息学分析确定NOD2在CC组织中的表达。将靶向NOD2(shNOD2)、shRNAs阴性对照(shNC... 目的 基于核苷酸结合寡聚化结构域受体2(NOD2)介导的AMP活化蛋白激酶(AMPK)/雷帕霉素靶蛋白(mTOR)信号通路探讨宫颈癌(CC)细胞恶性行为的机制。方法 生物信息学分析确定NOD2在CC组织中的表达。将靶向NOD2(shNOD2)、shRNAs阴性对照(shNC)以及NOD2过表达(NOD2)质粒和载体(Vec)转染CC细胞。通过CCK-8测定、集落形成和Transwell细胞侵袭测定来确定NOD2对CC细胞生长的影响。通过高通量RNA测序(RNA-Seq)进行转录组分析。Western blot试验检测细胞系中NOD2、AMPK/mTOR信号通路和自噬蛋白的表达。24只雌性BALB/c裸鼠随机分为4组,每组6只:载体组(Vec组)、NOD2过表达组(NOD2组)、shNC组和shNOD2组。构建小鼠远处转移模型,监测肺转移的荧光强度,计数肺转移结节的数量。结果 在线数据库分析显示,NOD2在CC组织中表达明显高于正常组织,并且不同分期的CC中NOD2的mRNA表达差异有统计学意义(P<0.05)。此外,NOD2的高表达与较差的总生存期和无病生存期相关(P<0.05)。NOD2过表达对CC细胞增殖、集落形成、迁移和侵袭具有促进作用,而NOD2敲低则相反。与体外结果一致,在转移的小鼠尾静脉注射模型中,NOD2组CC细胞的肺定殖、肺转移灶较Vec组增加(P<0.05),而shNOD2组CC细胞的肺定殖、肺转移灶较shNC组减少(P<0.05)。RNA-Seq结果显示NOD2表达与AMPK信号激活、mTOR信号抑制、自噬调节途径激活和自噬体形成显著相关。与shNC组相比,shNOD2组磷酸化AMPK、LC3蛋白表达水平减少(P<0.05),磷酸化mTOR、p62蛋白表达水平增加(P<0.05);与Vec组相比,NOD2组LC3、AMPK蛋白表达水平增加(P<0.05),磷酸化mTOR、p62蛋白表达水平减少(P<0.05)。与shNC组相比,shNOD2组GFP-mRFP-LC3的点积累减少(P<0.05);与Vec组相比,GFP-mRFP-LC3的点积累增加(P<0.05)。结论 NOD2可能通过AMPK/mTOR信号促进CC增殖、迁移和侵袭,其作用机制部分涉及自噬激活。 展开更多
关键词 核苷酸结合寡聚化结构域受体2 amp活化蛋白激酶 雷帕霉素靶蛋白 宫颈癌细胞 自噬
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黄芩苷调节cAMP/PKA/CREB信号通路对湿疹大鼠皮肤屏障功能的影响 被引量:1
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作者 王首帆 徐宜厚 +1 位作者 徐爱琴 朱立宏 《天津医药》 CAS 2024年第2期148-153,共6页
目的探讨黄芩苷(BA)调节环磷酸腺苷(cAMP)/蛋白激酶A(PKA)/cAMP反应元件结合蛋白(CREB)通路对湿疹大鼠皮肤屏障功能的影响。方法将SD大鼠随机分为对照组(NC组)、Model组、低剂量BA组(BA-L组,25 mg/kg)、中剂量BA组(BA-M组,50 mg/kg)、... 目的探讨黄芩苷(BA)调节环磷酸腺苷(cAMP)/蛋白激酶A(PKA)/cAMP反应元件结合蛋白(CREB)通路对湿疹大鼠皮肤屏障功能的影响。方法将SD大鼠随机分为对照组(NC组)、Model组、低剂量BA组(BA-L组,25 mg/kg)、中剂量BA组(BA-M组,50 mg/kg)、高剂量BA组(BA-H组,100 mg/kg)、泼尼松组(PNS组,25 mg/kg)、BAH+cAMP抑制剂(SQ22536)组(100 mg/kg+2.13 mg/kg)、BA-H+PKA抑制剂(H-89)组(100 mg/kg+5 mg/kg),每组12只。除NC组外,其余组大鼠均构建湿疹大鼠模型。建模成功2 d后,分组进行给药处理。检测湿疹面积及严重度指数(EASI)评分、经皮肤水分流失量(TEWL)、角质层含水量(WCSC)变化;酶联免疫吸附试验(ELISA)检测大鼠血清中免疫球蛋白E(IgE)、干扰素-γ(IFN-γ)、白细胞介素-4(IL-4)水平及大鼠背部受试区皮损组织中c AMP蛋白表达;HE染色检测大鼠背部受试区皮损组织病理变化;Western blot检测大鼠背部受试区皮损组织中水通道蛋白3(AQP3)、cathelicidin相关抗菌肽(CRAMP)、p-PKA、p-CREB蛋白表达。结果与NC组比较,Model组大鼠背部受试区皮损组织病理损伤严重,EASI评分、TEWL、IgE、IL-4水平升高,WCSC、IFN-γ水平、AQP3、CRAMP、cAMP、p-PKA、p-CREB蛋白水平降低(P<0.05)。与Model组比较,BA-L组、BA-M组、BA-H组、PNS组大鼠背部受试区皮损组织病理损伤减轻,EASI评分、TEWL、IgE、IL-4水平降低,WCSC、IFN-γ水平、AQP3、CRAMP、cAMP、p-PKA、p-CREB蛋白水平升高(P<0.05);且BA-L组、BA-M组、BA-H组上述指标变化呈剂量依赖性。SQ22536或H-89减弱了高剂量BA对湿疹大鼠皮肤屏障功能的改善作用。结论BA可能通过激活cAMP/PKA/CREB信号通路改善湿疹大鼠皮肤屏障功能。 展开更多
关键词 湿疹 黄芩苷 环磷酸腺苷/蛋白激酶A/camp反应元件结合蛋白通路 皮肤屏障功能
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川陈皮素调节AMPK/NLRP3信号通路对脂多糖诱导的肾小球系膜细胞炎性损伤的影响
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作者 罗丹 王燕 +1 位作者 丁旭 胡耀 《中药新药与临床药理》 CAS CSCD 北大核心 2024年第2期224-229,共6页
目的探讨川陈皮素(Nobiletin)调节AMP激活的蛋白激酶(AMPK)/NOD样受体蛋白3(NLRP3)信号通路对脂多糖(LPS)诱导的肾小球系膜细胞HBZY-1炎性损伤的影响。方法将HBZY-1细胞分为5组:正常组、LPS组(100 ng·m L^(-1)LPS)、川陈皮素组(100... 目的探讨川陈皮素(Nobiletin)调节AMP激活的蛋白激酶(AMPK)/NOD样受体蛋白3(NLRP3)信号通路对脂多糖(LPS)诱导的肾小球系膜细胞HBZY-1炎性损伤的影响。方法将HBZY-1细胞分为5组:正常组、LPS组(100 ng·m L^(-1)LPS)、川陈皮素组(100 ng·m L^(-1)LPS+40μmol·L^(-1)川陈皮素)、AMPK/NLRP3信号通路抑制剂雷帕霉素组(100 ng·m L^(-1)LPS+0.5μmol·L^(-1)雷帕霉素)、川陈皮素+雷帕霉素组(100 ng·m L^(-1)LPS+40μmol·L^(-1)川陈皮素+0.5μmol·L^(-1)雷帕霉素)。MTT法检测HBZY-1细胞毒性和增殖;ELISA法检测HBZY-1细胞白细胞介素(IL)-1β、IL-6、肿瘤坏死因子α(TNF-α)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、谷胱甘肽(GSH)含量;流式细胞术检测细胞凋亡;Western Blot法检测AMPK/NLRP3信号通路蛋白水平。结果与正常组比较,LPS组CAT、SOD、GSH水平、细胞OD值以及AMPK蛋白水平明显降低(P<0.05),细胞凋亡率、IL-1β、IL-6、TNF-α含量以及NLRP3蛋白水平明显升高(P<0.05)。与LPS组比较,川陈皮素组CAT、SOD、GSH水平、OD值以及AMPK蛋白水平明显升高(P<0.05),细胞凋亡率、IL-1β、IL-6、TNF-α含量以及NLRP3蛋白水平明显下降(P<0.05);而雷帕霉素组以上指标均呈现与川陈皮素组相反的趋势(P<0.05)。与川陈皮素组比较,川陈皮素+雷帕霉素组以上指标均呈现与川陈皮素组相反的趋势(P<0.05)。结论川陈皮素可能通过上调AMPK/NLRP3信号通路减轻LPS诱导的肾小球系膜细胞细胞炎性损伤。下调AMPK/NLRP3信号通路可消除川陈皮素对LPS诱导的肾小球系膜细胞细胞炎性损伤的改善作用。 展开更多
关键词 川陈皮素 amp激活的蛋白激酶/NOD样受体蛋白3(ampK/NLRP3)信号通路 脂多糖 肾小球系膜细胞 HBZY-1 炎性损伤
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基于AMPK通路探讨茶多酚改善糖尿病大鼠糖脂代谢机制
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作者 黄苏萍 林欢 +2 位作者 曾淑华 杨柳媛 许陆达 《山东中医药大学学报》 2024年第2期192-200,共9页
目的:探讨茶多酚从AMP活化蛋白激酶(AMPK)通路途径调控糖尿病大鼠糖脂代谢的机制。方法:经糖耐量试验筛选6周龄SD大鼠45只,按随机数字表法分为正常组10只和造模组35只,造模组糖尿病造模成功后剩余30只,根据体质量分层法和血糖水平分为... 目的:探讨茶多酚从AMP活化蛋白激酶(AMPK)通路途径调控糖尿病大鼠糖脂代谢的机制。方法:经糖耐量试验筛选6周龄SD大鼠45只,按随机数字表法分为正常组10只和造模组35只,造模组糖尿病造模成功后剩余30只,根据体质量分层法和血糖水平分为模型组、二甲双胍组和茶多酚组,每组各10只。各组均于每日下午灌胃,正常组与模型组给予无菌生理盐水,二甲双胍组给予二甲双胍水溶液,茶多酚组给予茶多酚。干预120 d后,检测各组大鼠的空腹血糖(FBG)、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C);酶联免疫吸附试验法检测肝脏乙酰辅酶A羧化酶(ACC)和激素敏感性脂肪酶(HSL);实时荧光定量法检测肝脏ACCmRNA、转录因子胆固醇调节元件结合蛋白1(SREBP-1)mRNA、3-羟基-3-甲基戊二酸单酰辅酶A还原酶(HMGCR)mRNA;免疫印迹法检测肝脏AMPKα1、磷酸化AMP活化蛋白激酶α1(P-AMPKα1)、SREBP1、HMGCR、肉毒碱棕榈酰转移酶1(CPT1)、葡萄糖转运蛋白4(GLUT4)和磷酸烯醇丙酮酸羧化激酶(PEPCK)。结果:与正常组比较,模型组大鼠的一般情况较差,FBG、TG、TC、LDL-C、ACC升高(P<0.05),SREBP1、HMGCR蛋白及mRNA表达升高(P<0.05),CPTI、PEPCK蛋白表达升高(P<0.05),HDL-C、HSL降低(P<0.05),AMPKα1、P-AMPKα1、GLUT4蛋白表达降低(P<0.05)。与模型组比较,茶多酚组大鼠的一般情况改善,TG、LDL-C、ACC降低(P<0.05),SREBP1、HMGCR蛋白及mRNA表达降低(P<0.05),PEPCK蛋白表达降低(P<0.05),HDL-C、HSL升高(P<0.05),AMPKα1、P-AMPKα1、GLUT4、CPT1蛋白表达升高(P<0.05)。与二甲双胍组比较,茶多酚组TC升高(P<0.05),FBG、TG、LDL-C、HDL-C、HSL、ACC、ACC mRNA、HMGCR mRNA、SREBP1 mRNA、AMPKα1、P-AMPKα1、SREBP1、HMGCR、CPT1、GLUT4、PEPCK相对表达量差异无统计学意义(P>0.05)。结论:茶多酚可能通过调节AMPK通路,影响HSL、HMGCR、SREBP1、CPTI、GLUT4和PEPCK,从而改善糖尿病大鼠糖脂代谢。 展开更多
关键词 糖尿病 茶多酚 二甲双胍 amp活化蛋白激酶通路 糖脂代谢 大鼠
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阿江榄仁酸由AMPK/mTOR/HO-1信号通路调控自噬对糖尿病视网膜病变影响
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作者 蒋晨 万新娟 +2 位作者 王绍飞 王晓虹 丁琳 《河北医药》 CAS 2024年第2期171-175,共5页
目的探讨阿江榄仁酸(arjunolic acid,AA)对糖尿病视网膜病变(diabetic retinopathy,DR)大鼠视网膜细胞自噬及AMPK/mTOR/HO-1信号通路的影响。方法以健康SD大鼠为研究对象,构建链脲佐菌素(STZ)诱导的糖尿病大鼠模型,随机分为对照组(Con)... 目的探讨阿江榄仁酸(arjunolic acid,AA)对糖尿病视网膜病变(diabetic retinopathy,DR)大鼠视网膜细胞自噬及AMPK/mTOR/HO-1信号通路的影响。方法以健康SD大鼠为研究对象,构建链脲佐菌素(STZ)诱导的糖尿病大鼠模型,随机分为对照组(Con)组、模型(STZ)组、AA低剂量(AAL,10 mg/kg)组和AA高剂量(AAH,10 mg/kg)组。连续给药10周后,HE染色检测视网膜组织病理结构;qRT-PCR检测视网膜组织白介素(IL)-1β、IL-6和线粒体丙酮酸转运载体(MPC)-1的mRNA表达;二氢乙锭(DHE)染色评估视网膜组织ROS产生;Western blot检测自噬和AMPK/mTOR/HO-1信号通路相关蛋白表达。结果与Con组比较,STZ组大鼠视网膜出现肿胀和空泡样变化等病理变化,中央视网膜ONL层厚度和细胞核计数明显降低(P<0.01);IL-1β、IL-6和MCP-1的mRNA水平显著增高(P<0.05);视网膜外核层(ONL)、内核层(INL)和神经节细胞层(GCL)中ROS产生增加(P<0.01);LC3II/I比率、HO-1和p-AMPK/AMPK蛋白表达显著降低,p62和p-mTOR/mTOR表达升高(P<0.01)。与STZ组比较,AAL和AAH组大鼠视网膜ONL厚度和细胞核计数逐渐升高,结构相对规整(P<0.05);AAH组IL-1β、IL-6和MCP-1的mRNA表达明显降低(P<0.05);视网膜ONL、INL和GCL中ROS产生逐渐降低(P<0.01);LC3II/I比率、p-AMPK/AMPK和HO-1表达逐渐升高,p62和p-mTOR/mTOR表达逐渐降低(P<0.01)。结论阿江榄仁酸可能是治疗DR的候选药物,可能机制为通过AMPK/mTOR/HO-1调节的自噬途径保护视网膜细胞免受STZ诱导的氧化应激和炎症损伤。 展开更多
关键词 阿江榄仁酸 糖尿病视网膜病变 ampK/mTOR/HO-1通路 自噬
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基于AMPK/sirt1/RANKL/OPG通路研究补阳还五汤促进骨质疏松性骨折大鼠愈合的机制
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作者 林玉玲 李杰玉 +3 位作者 李增一 刘琳 籍胤玺 金毅 《中国老年学杂志》 CAS 北大核心 2024年第1期133-137,共5页
目的基于AMP活化蛋白激酶(AMPK)/沉默信息调节因子(sirt)1/核转录因子(NF)-κB受体活化蛋白配体(RANKL)/骨保护素(OPG)信号通路,探究补阳还五汤促进骨质疏松性骨折大鼠骨折愈合的机制。方法将大鼠随机分成假手术组、模型组、补阳还五汤... 目的基于AMP活化蛋白激酶(AMPK)/沉默信息调节因子(sirt)1/核转录因子(NF)-κB受体活化蛋白配体(RANKL)/骨保护素(OPG)信号通路,探究补阳还五汤促进骨质疏松性骨折大鼠骨折愈合的机制。方法将大鼠随机分成假手术组、模型组、补阳还五汤低剂量组(6.25 g/kg)、补阳还五汤中剂量组(12.50 g/kg)和补阳还五汤高剂量组(25.00 g/kg)。除假手术组外,其余组均构建骨质疏松性骨折模型,并给予相应剂量药物干预。检测大鼠骨密度(BMD)值、骨折愈合评分及骨痂体积;自动生化分析仪测定血清碱性磷酸酶(ALP)、骨钙素、钙和磷水平;酶联免疫吸附试验(ELISA)检测股骨组织中的丙二醛(MDA)、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)水平;苏木素-伊红(HE)染色观察各组大鼠骨痂组织的病理形态;Western印迹检测股骨组织中AMPK/sirt1/RANKL/OPG通路蛋白表达。结果与假手术组相比,模型组骨痂骨小梁分布稀疏,成骨细胞大量减少且有纤维组织生成,骨痂体积、血清中ALP、骨钙素、钙和磷水平及股骨组织中MDA水平、RANKL蛋白水平显著升高(P<0.05),BMD值、骨折愈合评分、骨组织中SOD和GSH-Px水平和AMPK、sirt1、OPG蛋白水平显著降低(P<0.05)。与模型组相比,补阳还五汤低、中、高剂量组骨痂骨小梁分布较为密集,成骨细胞增加,骨痂体积、血清中ALP、骨钙素、钙和磷水平及股骨组织中MDA水平、RANKL蛋白水平显著降低(P<0.05),BMD值、骨折愈合评分、骨组织中SOD和GSH-Px水平和AMPK、sirt1、OPG蛋白水平显著升高(P<0.05)。结论补阳还五汤可能通过抑制氧化应激反应,调节AMPK/sirt1/RANKL/OPG通路,发挥对骨质疏松骨折大鼠的治疗作用。 展开更多
关键词 补阳还五汤 骨质疏松性骨折 氧化应激 amp活化蛋白激酶(ampK)/沉默信息调节因子(sirt)1/核转录因子(NF)-κB受体活化蛋白配体(RANKL)/骨保护素(OPG)通路
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超高矿化度AM/AMPS共聚物压裂液与交联过程流变学
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作者 田珍瑞 方波 +2 位作者 辛慧 卢拥军 许可 《应用化工》 CAS CSCD 北大核心 2024年第5期1086-1092,共7页
对不同矿化度、不同盐溶液中AM/AMPS压裂液流变性能及其在超高矿化度时的交联凝胶状态与流变学性质以及交联过程进行了研究。结果表明,AM/AMPS压裂液KCl与CaCl_(2)溶液中黏度与弹性模量下降,且CaCl_(2)的影响更显著;而超高矿化度镁盐溶... 对不同矿化度、不同盐溶液中AM/AMPS压裂液流变性能及其在超高矿化度时的交联凝胶状态与流变学性质以及交联过程进行了研究。结果表明,AM/AMPS压裂液KCl与CaCl_(2)溶液中黏度与弹性模量下降,且CaCl_(2)的影响更显著;而超高矿化度镁盐溶液对压裂液黏度与黏弹性有增强作用。在超高矿化度的不同盐溶液中,AM/AMPS均可以与有机锆交联剂形成能完全挑挂凝胶,应变扫描结果证明,交联后压裂液表现出典型的凝胶特征。AM/AMPS压裂液在高矿化度盐溶液以及水溶液中的30℃恒温小振幅振荡交联过程可用四参数交联流变动力学方程描述,金属盐离子可以提高凝胶强度,且二价盐的提高更为显著。AM/AMPS压裂液升温小振幅振荡交联过程存在缓速交联与快速交联两个阶段,适当升温有利于交联反应。AM/AMPS压裂液在自来水与一价盐溶液中升温大振幅振荡交联过程与升温小振幅振荡交联过程相似;在二价盐溶液中交联过程受剪切影响较大,适当提高剪切,有利于AM/AMPS压裂液在盐溶液中交联。研究获得了超高矿化度AM/AMPS压裂液新体系,有望为AM/AMPS压裂液工程应用提供指导。 展开更多
关键词 AM/ampS共聚物压裂液 超高矿化度 流变性 交联流变动力学 大振幅振荡剪切
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Lightweight Design of Automobile Drive Shaft Based on the Characteristics of Low Amplitude Load Strengthening 被引量:17
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作者 ZHENG Songlin XU Honghui +3 位作者 FENG Jinzhi ZHENG Zuanxi WANG Youtao LU Leilei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第6期1111-1115,共5页
There are two kinds of internationally recognized approaches in terms of lightweight design.One is based on fatigue accumulated damage theory to achieve better reliability by optimal structural design; another is to u... There are two kinds of internationally recognized approaches in terms of lightweight design.One is based on fatigue accumulated damage theory to achieve better reliability by optimal structural design; another is to use high performance lightweight materials.The former method takes very few considerations on the structural strengthening effects caused by the massive small loads in service.In order to ensure safety,the design is usually conservative,but the strength potential of the component is not fully exerted.In the latter method,cost is the biggest obstacle to lightweight materials in automotive applications.For the purpose of light weighting design on a fuel cell vehicle,the new design method is applied on drive shafts.The method is based on the low amplitude load strengthening characteristics of the material,and allows the stress,corresponding to test load,to enter into the strengthened range of the material.Under this condition,the light weighting design should assure that the reliability of the shaft is not impaired,even maximizes the strength potential of machine part in order to achieve the weight reduction and eventually to reduce the cost.At last,the feasibility of the design is verified by means of strength analysis and modal analysis based on the CAD model of light weighted shaft.The design applies to the load case of half shaft in independent axle,also provides technological reference for the structural lightweight design of vehicles and other machineries. 展开更多
关键词 fuel cell vehicle drive shaft low amplitude load strengthening lightweight design
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A fatigue damage model for rock salt considering the effects of loading frequency and amplitude 被引量:9
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作者 Wang Yasong Ma Linjian +1 位作者 Fan Pengxian Chen Yan 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第5期955-958,共4页
With the large-scale construction of underground gas storage in salt deposit, much more efforts have been made to assess the fatigue properties of rock salt. The fatigue damage processes the primary, steady,and accele... With the large-scale construction of underground gas storage in salt deposit, much more efforts have been made to assess the fatigue properties of rock salt. The fatigue damage processes the primary, steady,and accelerated phases, which is similar to the axial irrecoverable deformation compiled from the loci of the loading cycles of rock salt. The cumulative fatigue damage increases with a decrease in the loading frequency and with an increase in the stress amplitude within the range tested. To take into account the effects of loading frequency and amplitude on the fatigue behavior of rock salt subjected to cyclic loading, a low cycle fatigue damage model was exclusively established combined with the Manson–Coffin formula. The proposed damage evolution equation was validated with experimental results and proved to be efficient in the prediction of fatigue damage tendency of rock salt under different loading frequencies and amplitudes. 展开更多
关键词 Rock salt FATIGUE FREQUENCY Stress amplitude DAMAGE
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