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Chinese Physics B 2015年第1期24卷 247-252页

作者：刘国昌李超方广有 Key laboratory of Electromagnetic radiation and Sensing Technology Chinese Academy of Sciences

We present the design and the experimental demonstration of an invisible cloak with irregular shape by using tensor transmission line（TL） metamaterials. The fabricated cloak consists of tensor TL unit cells exhibiting anisotropic effective material parameters, while the background medium consists of isotropic TL unit cells. The simulated and the measured field patterns around the cloak show a fairly good agreement, both demonstrate that the fabricated cloak can shield the cloaked interior area from electromagnetic fields without perturbing the external fields. The scattering of the cloaked perfect electric conductor（PEC） is minimized. Furthermore, the nonresonant property of the TL structure results in a relatively broad bandwidth of the realized cloak, which is clearly observed in our experiment.

关键词： invisible cloak irregular shape tensor transmission line metamaterials

EFFECT ON BIOLOGICAL BEHAVIOR OF CHEMOTHERAPY-RESISTANT TUMOR CELLS BY HUMAN WILD-TYPE p53,GM-CSF AND B7-1 GENES VIA RECOMBINANTADENOVIRUS

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Chinese Journal of Cancer Research 2000年第2期12卷 105-114页

作者：范国昌吴祖泽王艳飞吴世凯邱兆华 Department of experimental Hematology Beijing Institute of Radiation Medicine Beijing China

Objective: To explore the effect on biological behavior of chemotherapy-resistant tumor cells by human wild-type p53, GM-CSF and B7-1 genes mediated via recombinant adenovirus. Methods: p53-abnormal KB-v200 (VCR resistant) and KB-s (VCR sensitive) cell lines were used as model tumor cells, which are resistant and sensitive to chemotherapeutic drugs respectively. After infected with recombinant adenovirus carrying human wild-type p53, GM-CSF and B7-1 genes, changes in biological behavior (including drug sensitivity) of these two kinds of gene-transduced cancer cells were observed. Results: Both of the cell lines were susceptible to adenovirus, all of three exogenous genes (p53, GM-CSF and B7-1) could be effectively expressed in these cell lines, their growth was suppressed, and apoptosis was induced. The drug-pumping-out function of Pgp glycoprotein on the cytomembrane of drug-resistant KB-v200 cells was markedly affected 48h after transfection of the recombinant adenovirus, revealed by increase of the amount of rhodamine 123 accumulation in the cells. The MTT assay also indicated the reversal of their sensitivity to VCR *** vivo experiment in nude mice it was demonstrated reduction of tumorigenicity of the KB-v200 cells or KB-s cells infected with the recombinant adenovirus, and increase of their sensitivity to VCR. Conclusion: The clinical application of this recombinant adenovirus carrying agents might be more effective in treatment of tumors with multidrug resistance(MDR).

关键词： Tumor gene therapy multidrug resistance adenoviral vector

Basic roles of key molecules connected with NMDAR signaling pathway on regulating learning and memory and synaptic plasticity

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Journal of Medical Colleges of PLA(China) 2016年第4期31卷 212-218页

作者： Hui Wang Rui-Yun Peng Department of experimental Pathology Beijing Institute of Radiation Medicine

With key roles in essential brain functions ranging from the long-term potentiation(LTP) to synaptic plasticity,the N-methyl-D-aspartic acid receptor(NMDAR) can be considered as one of the fundamental glutamate receptors in the central nervous *** role of NMDA R was first identified in synaptic plasticity and has been extensively *** molecules,such as Ca^(2+),postsynaptic density 95(PSD-95),calcium/calmodulin-dependent protein kinase II(Ca MK II),protein kinase A(PKA),mitogen-activated protein kinase(MAPK) and cyclic adenosine monophosphate(c AMP) responsive element binding protein(CREB),are of special importance in learning and *** review mainly focused on the new research of key molecules connected with learning and memory,which played important roles in the NMDAR signaling pathway.

关键词： N-methyl-D-aspartic acid receptors Long-term potentiation Synaptic plasticity Learning and memory

A virtual thermometer for ultrahigh-temperature-pressure experiments in a large-volume press

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Matter and radiation at Extremes 2024年第4期9卷 98-110页

作者： Bingtao Feng Longjian Xie Xuyuan Hou Shucheng Liu Luyao Chen Xinyu Zhao Chenyi Li Qiang Zhou Kuo Hu Zhaodong Liu Bingbing Liu State Key laboratory of Superhard Materials Synergetic Extreme Condition User FacilityCollege of PhysicsJilin UniversityChangchun 130012China Department of Earth Sciences University College LondonLondon WC1E 6BSUnited Kingdom Earth and Planetary laboratory Carnegie Institute for ScienceWashingtonDistrict of Columbia 20015USA College of Earth Sciences Jilin UniversityChangchun 130012China

Ultrahigh-temperature-pressure experiments are crucial for understanding the physical and chemical properties of *** recent development of boron-doped diamond(BDD)heaters has made such melting experiments possible in large-volume ***,estimates of temperatures above 2600 K and of the temperature distributions inside BDD heaters are not well constrained,owing to the lack of a suitable ***,we establish a three-dimensional finite element model as a virtual thermometer to estimate the temperature and temperature field above 2600 *** advantage of this virtual thermometer over those proposed in previous studies is that it considers both alternating and direct current heating modes,the actual sizes of cell assemblies after compression,the effects of the electrode,thermocouple and anvil,and the heat dissipation by the pressure-transmitting *** virtual thermometer reproduces the power-temperature relationships of ultrahigh-temperature-pressure experiments below 2600 K at press loads of 2.8-7.9 MN(~19 to 28 GPa)within experimental *** temperatures above 2600 K predicted by our virtual thermometer are within the uncertainty of those extrapolated from power-temperature relationships below 2600 ***,our model shows that the temperature distribution inside a BDD heater(19-26 K/mm along the radial direction and<83 K/mm along the longitudinal direction)is more homogeneous than those inside conventional heaters such as graphite or LaCrO_(3) heaters(100-200 K/mm).Our study thus provides a reliable virtual thermometer for ultrahigh-temperature experiments using BDD heaters in Earth and material sciences.

关键词： virtual ultrahigh sizes

Spontaneous ignition of corrugated cardboard under dynamic high radiant flux

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Defence Technology（防务技术） 2024年第10期40卷 65-77页

作者： Liu Liu Yan Gu Hong Yang Xing Wang Yang Zhou Xiaogan Dai Yong Han Shanggang Wen Ming Li Congmei Lin Changgen Feng Fei Tang Yushi Wen Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621999China State Key laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China State Key laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China Institute of Applied Physics and Computational Mathematics China Academy of Engineering PhysicsBeijing 100088China

Understanding the response of solid combustibles under high radiant fluxes is critical in predicting the thermal damage from extreme *** the more moderate radiant fluxes in conventional hydrocarbon fires,extreme events such as strong explosion,concentrated sunlight and directed energy can generate dynamic radiant fluxes at the MW/m^(2) level,creating a unique threat to *** study investigates the pyrolysis and spontaneous ignition behaviors of corrugated cardboard by using both experimental and numerical methods,under 10-cm dynamic high radiant fluxes ranging from 0.2 to 1.25 MW/m^(2) for 10 *** spontaneous ignition process at dynamic high radiant fluxes was recorded and *** ignition modes were found at the critical radiant flux of 0.4 MW/m^(2),namely hot-gas spontaneous ignition and hot-residue piloted *** latter is not the focus of this paper due to its extremely small probability of *** research reveals that the increase in flux intensity induces shorter delay times for both pyrolysis and ignition,lower ignition energy density,along with a corresponding rise in the critical mass flux and surface temperature at ignition *** simulation results are generally aligned with the experimental findings,despite some divergences may be attributed to model simplifications and parameter *** work contributes to a deeper insight into material behavior under extreme radiation,with valuable implications for fire safety and hazard assessment.

关键词： Extreme radiation Fire safety Corrugated cardboard Pyrolysis Ignition temperature

Analytical methods for investigating in vivo fate of nanoliposomes:A review

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Journal of Pharmaceutical Analysis 2018年第4期8卷 219-225页

作者： Chong Su Yingze Liu Yang He Jingkai Gu College of Life Science Jilin University Department of Pharmaceutical Sciences and experimental therapeutics College of Pharmacy University of lowa

Nanoliposomes are considered to be the most successful nanoparticle drug delivery system, but their fate in vivo has not been fully understood due to lack of reliable bioanalytical methods, which seriously limits the development of liposomal drugs. Hence, an overview of currently used bioanalytical methods is imperative to lay the groundwork for the need of developing a bioanalytical method for liposome measurements in vivo. Currently, major analytical methods for nanoliposomes measurement in vivo include fluorescence labeling, radiolabeling, magnetic resonance imaging（MRI）, mass spectrometry and computed tomography. In this review, these bioanalytical methods are summarized, and the advantages and disadvantages of each are discussed. We provide insights into the applicability and limitations of these analytical methods in the application of nanoliposomes measurement in vivo, and highlight the recent development of instrumental analysis techniques. The review is devoted to providing a comprehensive overview of the investigation of nanoliposomes design and associated fate in vivo, promoting the development of bioanalytical techniques for nanoliposomes measurement, and understanding the pharmacokinetic behavior, effectiveness and potential toxicity of nanoliposomes in vivo.

关键词： Liposomes Analytical methods In vivo fate Liposomal drug

Particle size dependence of the microsegregation and microstructure in the atomized Ni-based superalloy powders:Theoretical and experimental study

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Journal of Materials Science & Technology 2024年第4期171卷 54-65页

作者： Jikang Li Mingsheng Yang Yunfei Cai Yuanyuan Zhang Qingshuai Feng Jiantao Liu Tong Liu Key laboratory of Aerospace Materials and Performance(Ministry of Education)School of Materials Science and Engineering Beihang UniversityBeijing 100191China Central Iron and Steel Research Institute Beijing 100081China

The microstructure and microsegregation of atomized powder,which depend on their sizes,are of great importance to the mechanical properties of the consolidated bulk ***,it is necessary to reveal the relationship between particle size and powder *** effects of particle size on the so-lidification characterization of the atomized Ni-based superalloy powders were studied via finite element *** on the simulations,a model was developed to predict the microsegregation and mi-crostructure of atomized powders with different sizes and study the influence of thermal history on the powder attributes during the atomization *** radiation heat transfer and temperature gradi-ent within the rapid solidification alloy powders were taken into account in this *** validating the accuracy of the model,the predictions of the present model were compared with the microsegregation and microstructure of the specific size powder close to the screen mesh *** results showed that mi-crostructure depended primarily on the temperature gradient within the powder,while the solidification rate had a more significant effect on the *** model predicted microstructure features in agreement with the experiment,and for microsegregation,the deviations of prediction for most ele-ments were less than 10%.This work provides a new model to precisely predict the microsegregation and microstructure of the atomized alloy powders and sets a foundation to control the powder features for various engineering applications.

关键词： Particle size Solidification microstructure Microsegregation Numerical simulation

Pathogenesis of NSAID-induced gastric damage:Importance of cyclooxygenase inhibition and gastric hypermotility

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World Journal of Gastroenterology 2012年第18期18卷 2147-2160页

作者： Koji Takeuchi Department of Pharmacology and experimental therapeutics Division of Pathological SciencesKyoto Pharmaceutical UniversityKyoto 607-8414Japan

This article reviews the pathogenic mechanism of nonsteroidal anti-inflammatory drug(NSAID)-induced gastric damage,focusing on the relation between cyclooxygenase(COX) inhibition and various functional ***,such as indomethacin,at a dose that inhibits prostaglandin(PG) production,enhance gastric motility,resulting in an increase in mucosal permeability,neutrophil infiltration and oxyradical production,and eventually producing gastric *** lesions are prevented by pretreatment with PGE 2 and antisecretory drugs,and also via an atropine-sensitive mechanism,not related to antisecretory *** neither rofecoxib(a selective COX-2 inhibitor) nor SC-560(a selective COX-1 inhibitor) alone damages the stomach,the combined administration of these drugs provokes gastric ***-560,but not rofecoxib,decreases prostaglandin E 2(PGE 2) production and causes gastric hypermotility and an increase in mucosal ***-2 mRNA is expressed in the stomach after administration of indomethacin and SC-560 but not *** up-regulation of indomethacin-induced COX-2 expression is prevented by atropine at a dose that inhibits gastric *** addition,selective COX-2 inhibitors have deleterious influences on the stomach when COX-2 is overexpressed under various conditions,including adrenalectomy,arthritis,and Helicobacter *** summary,gastric hypermotility plays a primary role in the pathogenesis of NSAID-induced gastric damage,and the response,causally related with PG deficiency due to COX-1 inhibition,occurs prior to other pathogenic events such as increased mucosal permeability;and the ulcerogenic properties of NSAIDs require the inhibition of both COX-1 and COX-2,the inhibition of COX-1 upregulates COX-2 expression in association with gastric hypermotility,and PGs produced by COX-2 counteract the deleterious effect of COX-1 inhibition.

关键词： Non-steroidal anti-inflammatory drug Gastric damage Pathogenesis Gastric motility Neutrophil

Design,modeling and experimental investigation of a novel solar sail with high area-to-mass ratios for efficient solar sailing

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Chinese Journal of Aeronautics 2024年第10期37卷 234-248页

作者： Zhongjing REN Chengyang LI Ke WU Ziran WANG Haipeng WANG Peng YAN Key laboratory of High-efficiency and Clean Mechanical Manufacture(Ministry of Education) School of Mechanical EngineeringShandong UniversityJinan 250061China China Manned Space Agency Beijing 100071China

Solar sailing is a promising propellant-free approach to propelling spacecraft in ***,the propelling efficiency of conventional solar sail spacecraft is limited by their areato-mass *** paper proposes a novel design of micro solar sails with area-to-mass ratios above 100 m2/kg for next-generation chip-scale *** thin films developed by Microelectromechanical Systems(MEMS)technologies were patterned into grid microstructures,and theoretical analysis of a sail prototype was *** electro-thermal and thermo-mechanical models of the solar sail in geospace were established by taking effects of Joule heating,solar radiation,and thermal re-emission into consideration,enabling rapid prediction of its threedimensional(3-D)reconfiguration from the as-released two-dimensional(2-D)*** of the ChipSail’s acceleration arising from the sail’s morphing was also analytically *** and characterization of the sail prototype made of multiple Al/Ni50Ti50 bilayer beams were ***-situ SEM imaging of the sail prototype in vacuum chamber witnessed an active and continuous 3-D reconfiguration under Joule heating,and over 90deformation was detected by applying a DC voltage of 0.078 *** and experimental work on the solar sail with at least 10 times higher area-to-mass ratios than conventional ones will lay a solid foundation for efficient solar sailing.

关键词： Solar sails Solar sailing High area-to-mass ratios Solar radiation pressure ChipSail

Erythropoietin and cerebral vascular protection:role of nitric oxide

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Acta Pharmacologica Sinica 2006年第11期27卷 1389-1394页

作者： Anantha VijayRSANTHANAM Zvonimir SKATUSIC Departments of Anesthesiology and Molecular Pharmacology and experimental therapeutics Mayo Clinic College of MedicineRochesterMinnesota 55905USA

Cerebral vasospasm after subarachnoid hemorrhage(SAH)is a major clinical prob-lem causing cerebral ischemia and *** pathogenesis of vasospasm isrelated to a number of pathological processes including endothelial damage andalterations in vasomotor function leading to narrowing of arterial diameter and asubsequent decrease in cerebral blood *** of the tissue protectiveeffects of erythropoietin(EPO)stimulated the search for therapeutic applicationof EPO for the prevention and treatment of cerebrovascular *** stud-ies have identified the role of EPO in vascular protection mediated by the preser-vation of endothelial cell integrity and stimulation of *** this review,we discuss the EPO-induced activation of endothelial nitric oxide(NO)synthaseand its contribution to the prevention of cerebral vasospasm.

关键词： cerebral vasospasm tissue protection nitric oxide synthase endothelium