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Hu Yinlong Hua Tianyang Chen Michael Z. Q. Shi Shang Sun Yonghui 《Nonlinear dynamics》2021,105(1):99-112
Nonlinear Dynamics - In this paper, the instability of semi-active control systems caused by the utilization of semi-active inerters is analyzed. The purpose of this study is to demonstrate the... 相似文献
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Shi Zhiguo Ran Lixin Chen Kangsheng 《电子科学学刊(英文版)》2006,23(3):433-436
Chaotic Colpitts circuits with fundamental frequency f^* beyond 1GHz are studied by both circuit simulation and experiment using Philips' broadband transistor with threshold frequency of 25GHz. For the basic configuration of Colpitts circuit with f^* of about 1,6GHz, broadband continuous power spectra could be obtained from both circuit simulations and experiments. The harmonics of the observed signal from Agilent PSA/ESA spectrum analyzer are as noticeable as far as 12GHz. A modified Colpitts circuit structure employing the parasitic inductance of BJT (Bipolar Junction Transistor) is also proposed and investigated. By circuit simulation, chaotic attractor and broadband continuous power spectra could be obtained from the modified Colpitts circuit with f^* of about 3.5GHz. Because the parasitic effects of the prototype board, the experiment result of the modified Colpitts circuit does not agree well with the simulation result. The gap between the simulation and experimental result could be bridged by replacing the lumped circuit elements with distributed ones. 相似文献
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Shi Lingfeng Guo Baolong 《电子科学学刊(英文版)》2006,23(5):708-712
The paper presents a new algorithm of NonLinearly Adaptive Interpolation (NLAI). NLAI is based on both the gradients and the curvature of the signals with the predicted subsection, it is characterized by adaptive nonlinear interpolation method with extracting the characteristics of signals, Experimental research testifies the validity of the algorithm using the echoes of the Ground Penetrating Radar (GPR). A comparison of this algorithm with other traditional algorithms demonstrates that it is feasible. 相似文献
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Birui Shi Yan Zhang Baolin Huang Huiping Lin Qiong Zhou Yujue Wang Zheng Cai Menghua Liu 《Molecules (Basel, Switzerland)》2022,27(3)
With the widespread clinical use of drug combinations, the incidence of drug–drug interactions (DDI) has significantly increased, accompanied by a variety of adverse reactions. Drug transporters play an important role in the development of DDI by affecting the elimination process of drugs in vivo, especially in the pathological state. Tubulointerstitial fibrosis (TIF) is an inevitable pathway in the progression of chronic kidney disease (CKD) to end-stage renal disease. Here, the dynamic expression changes of eleven drug transporters in TIF kidney have been systematically investigated. Among them, the mRNA expressions of Oat1, Oat2, Oct1, Oct2, Oatp4C1 and Mate1 were down-regulated, while Oat3, Mrp2, Mrp4, Mdr1-α, Bcrp were up-regulated. Pearson correlation analysis was used to analyze the correlation between transporters and Creatinine (Cr), OCT2 and MATE1 showed a strong negative correlation with Cr. In contrast, Mdr1-α exhibited a strong positive correlation with Cr. In addition, the pharmacokinetics of cimetidine, ganciclovir, and digoxin, which were the classical substrates for OCT2, MATE1 and P-glycoprotein (P-gp), respectively, have been studied. These results reveal that changes in serum creatinine can indicate changes in drug transporters in the kidney, and thus affect the pharmacokinetics of its substrates, providing useful information for clinical use. 相似文献