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Transdermal Drug Delivery by Electroporation： The Effects of Surfactants on Pathway Lifetime and Drug Transport

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Chinese Journal of Chemical Engineering 2007年第3期15卷 397-402页

作者：蒋国强朱德权昝佳丁富新 Department of Chemical Engineering Tsinghua University Beijing 100084 China

Electroporation creates aqueous pathways by short high-voltage pulses resulting in a transient perme- abilization of stratum corneum and an increase in the transdermal delivery *** the aqueous pathways will reseal after pulsing,which leads to the rapid drop of transdermal *** the present study,the surfactants were added to the donor solution to hinder the shrinkage and resealing of the electropore,and to prolong the lifetime of the aqueous pathways with the consideration that the surfactants could reduce the surface energy of the electropore. These effects of surfactants were demonstrated by the dynamic electrical resistance of the skin and the fluorescent imaging of the local transport ***(PIX)was transported percutaneously in the presence of surfac- tants in *** to the longer lifetime of aqueous pathways,together with the promotion of PIX availability at the barrier exterior and the improvement in the partition of PIX into the aqueous pathways,the presence of surfac- tants led to a remarkable increase in the transdermal delivery rate during electroporation and a significant growth of the accumulative transdermal amount of PIX.

关键词： transdermal drug delivery skin electroporation surfactant aqueous pathway

Simultaneous multi-parameter observation of Harring-tonine-treating HL-60 cells with both two-photon and confocal laser scanning microscopy

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Science China(Life Sciences) 2001年第4期44卷 383-391页

作者：张春阳李艳平马辉李素文薛绍白陈瓞延 Molecular and Nano Sciences Laboratory Department of Physics Tsinghua University Beijing 100084 China

Harringtonine (HT), a kind of anticancer drug isolated from Chinese herb-Cephalotaxus hainanensis Li, can induce apoptosis in promyelocytic leukemia HL-60 cells. With both two-photon laser scanning microscopy and confocal laser scanning microscopy in combination with the fluores-cent probe Hoechst 33342, tetramethyrhodamine ethyl ester (TMRE) and Fluo 3-AM, we simulta-neously observed HT-induced changes in nuclear morphology, mitochondrial membrane potential and intracellular calcium concentration ([Ca2+]i) in HL-60 cells, and developed a real-time, sensitive and invasive method for simultaneous multi-parameter observation of drug- treating living cells at the level of single cell.

关键词： two-photon laser scanning microscopy, confocal laser scanning microscopy, Harringtonine, HL-60 cells.

PI force feedback control for large flexible structure vibration with active tendons

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Acta Mechanica Sinica 2008年第6期24卷 721-725页

作者： Tieneng Guo Qiuhai Lu Junfeng Li School of Aerospace Tsinghua University 100084 Beijing China College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology 100124 Beijing China

Active tendon, consisting of a displacement actuator and a collocated force sensor, was first presented by Preumont and his co-workers to attenuate the vibration of large flexible space structures, and the control algorithm adopted by them was integral force feedback. This paper presents a new proportional-integral （PI） force feedback algorithm to achieve larger damping ratios for the structure without the requirement of structure model. Stability of the control system is shown, and simulations of a structure similar to JPL-MPI demonstrate the effectiveness of the proposed algorithm for vibration control of space structures.

关键词： Vibration control Active tendon PI force feedback control

Characteristics of Baicalin Synergy with Penicillin or Notopterygium Ethanol Extracts Against Staphylococcus aureus

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tsinghua Science and Technology 2006年第4期11卷 459-461页

作者：孟甄郑进燮游雪甫邢东明王伟杜力军 Laboratory of Pharmaceutical Sciences Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

Baicalin facilitates the effectiveness of both penicillin and Notopterygium ethanol extracts （NEE） on Staphylococcus aureus. Two Staphylococcus aureus strains, ATCC29213 and 03-21 （a clinical isolate）, were tested. When combined with 128 μ***^-1 of baicalin, the minimum inhibitory concentration （MIC） of penicillin was reduced from 0.25 μ***^-1 to 0.06 μ***^-1, while that of NEE was reduced from 32 μg·mL^-1 to 8μg·mL^-1 against ATCC29213. Against the 03-21 strain, the MIC of penicillin was reduced from 4 μ***^-1 to 1 μ***^-1, while that of NEE was reduced from 32 μ***^-1 to 4 μg·mL^-1. Viable number counting results show that combination of baicalin and penicillin acts on the killing mechanism, while the baicalin and NEE acts on the inhibition. These results show that baicalin acts as a synergistic ally with both penicillin and NEE but has different modes of action.

关键词： baicalin synergy minimum inhibitory concentration Staphylococcus aureus

SEMICLASSICAL LIMIT FOR BIPOLAR QUANTUM DRIFT-DIFFUSION MODEL

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Acta Mathematica Scientia 2009年第2期29卷 285-293页

作者：琚强昌陈丽 Institute of Applied Physics and Computational Mathematics Department of Mathematical Sciences Tsinghua University

Semiclassical limit to the solution of transient bipolar quantum drift-diffusion model in semiconductor simulation is discussed. It is proved that the semiclassical limit of this solution satisfies the classical bipol... 详细信息

关键词： Quantum drift-diffusion weak solution semiclassical limit bipolar

End-Output Coupling Efficiency Measurement of Silicon Wire Waveguides Based on Correlated Photon Pair Generation

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Chinese Physics Letters 2013年第7期30卷 92-95页

作者： LV Ning ZHANG Wei GUO Yuan ZHOU Qiang HUANG Yi-Dong PENG Jiang-De State Key Laboratory on Integrated Optoelectronics Tsinghua National Laboratory for Information Science and TechnologyDepartment of Electronic EngineeringTsinghua UniversityBeijing 100084

A method to measure the end-output coupling efficiencies between silicon wire waveguides(SWWs)and optical fibers is proposed and *** end-output coupling efficiency is calculated through four measured counting rates based on the correlated photon pair generation in the *** provides a way to investigate and optimize the coupling processes at the input and output end of the optical waveguides separately.

关键词： Efficiency optical waveguides

On opportunistic spectrum efficiency in cognitive radio systems

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High Technology Letters 2009年第2期15卷 170-174页

作者：王鹏 Zhong Xiaofeng Xiao Limin Zhou Shidong Wang Jing Bai Yong State Key Laboratory on Microwave and Digital Communications Tsinghna National Laboratory for Information Science and Technology Department of Electronic Engineering Tsinghua University Beijing 100084 P.R. China DoCoMo Beijing Communications Laboratories Compary Limited Beijing 100080 P.R. China

The performance bound of cognitive radio systems is *** use opportunistic spectrum effi-ciency(OSE)as the performance metric,and point out that the maximum achievable OSE can be used toevaluate the maximum value that the introduction of secondary users can add to the conventional *** on assumptions of the PU s traffic model and some reasonable approximations,the ex-pression of OSE is obtained and the maximum achievable OSE is derived by solving an optimization *** results are verified by computer simulation.

关键词： cognitive radio opportunistic spectrum access opportunistic spectrum efficiency

A New Atmospheric Pressure Microwave Plasma Source (APMPS)

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Plasma Science and Technology 2008年第1期10卷 83-88页

作者：刘亮张贵新李银安朱志杰王新新罗承沐 Department of Electrical Engineering and Applied Electronic Technology Tsinghua University Beijing 100084 China Institute of Physics Chinese Academy of Sciences Beijing 100080 China

An atmospheric pressure microwave plasma source （APMPS） that can generate a large volume of plasma at an atmospheric pressure has been developed at tsinghua University. This paper presents the design of this APMPS, the theoretical consideration of microwave plasma ignition and the simulation results, including the distributions of the electric field and power density inside the cavity as well as the accuracy of the simulation results. In addition, a method of producing an atmospheric pressure microwave plasma and some relevant observations of the plasma are also provided. It is expected that this research would be useful for further developing atmospheric pressure microwave plasma sources and expanding the scope of their applications.

关键词： microwave plasma atmospheric pressure microwave plasma

Cavity optomechanics： Manipulating photons and phonons towards the single-photon strong coupling

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Chinese Physics B 2018年第2期27卷 166-183页

作者：刘玉龙王冲张靖刘玉玺 Institute of Microelectronics Tsinghua University tsinghua National Laboratory for Information Science and Technology (TNList) Department of Automation Tsinghua University

Cavity optomechanical systems provide powerful platforms to manipulate photons and phonons, open potential ap- plications for modern optical communications and precise measurements. With the refrigeration and ground-state cooling technologies, studies of cavity optomechanics are making significant progress towards the quantum regime including non- classical state preparation, quantum state tomography, quantum information processing, and future quantum internet. With further research, it is found that abundant physical phenomena and important applications in both classical and quan- tum regimes appeal as they have a strong optomechanical nonlinearity, which essentially depends on the single-photon optomechanical coupling strength. Thus, engineering the optomechanical interactions and improving the single-photon optomechanical coupling strength become very important subjects. In this article, we first review several mechanisms, theoretically proposed for enhancing optomechanical coupling. Then, we review the experimental progresses on enhancing optomechanical coupling by optimizing its structure and fabrication process. Finally, we review how to use novel structures and materials to enhance the optomechanical coupling strength. The manipulations of the photons and phonons at the level of strong optomechanical coupling are also summarized.

关键词： optomechanical systems single-photon strong coupling controllable photons and phonons trans-port