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miRNAs modulate the drug response of tumor cells

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Science China(life sciences) 2009年第9期52卷 797-801页

作者： WU XueMei1,3 & xiao HuaSheng1,2.1 Center of Functional Genomics,key {2. of System Biology,Shanghai institutes for Biological sciences,chinese academy of sciences,Shanghai 2.0031,China 2.National Engineering Center for Biochip at Shanghai,Shanghai 2.12.3,China 3 Graduate University of chinese academy of sciences,Shanghai 2.0031,China Center of Functional Genomics Key Laboratory of System Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China Graduate University of chinese academy of sciences Shanghai China National Engineering Center for Biochip at Shanghai Shanghai China

Chemotherapy is one of the major treatments of malignant carcinomas. However,its efficiency is affected by both intrinsic and acquired resistance to anticancer drugs. The cellular mechanisms of drug resistance include the overexpression of energy-dependent transporters that eject anticancer drugs from cells such as p-glycoprotein and multidrug resistance related protein (MRP),the mutation of drug targets,the activation of DNA repair pathways,the defects in cellular death pathways and so on. The genetic and epigenetic changes of these genes can lead to cancer drug resistance. Among these mechanisms,microRNAs (miRNAs) which are critical and essential for many important processes such as development,differentiation,and even carcinogenesis have been reported to regulate the chemosen-sitivity of tumor cells. In this paper we briefly review the relationship between miRNA and cancer drug resistance.

关键词： cancer drug resistance miRNAs

Potential energy surfaces for low-lying electronic states of SO_2

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Science China Chemistry 2006年第4期49卷 289-295页

作者： lI Anyang1, SUO Bing2. WEN Zhenyi2.& WANG Yubin2.1. Shanxi key laboratory of Physico-inorganic Chemistry, Department of Chemistry, Northwest University, Xi’an 710069, China 2. {2. of Modern physics, Northwest University, Xi’an 710069, China Shanxi key laboratory of Physico-inorganic Chemistry Department of Chemistry Northwest University Xi’an China institute of Modern physics Northwest University Xi’an China

The potential energy surfaces for the nine low-lying electronic states of SO2.have been constructed by using the multi-reference second order perturbation theory (MRPT2. with the basis set cc-pVTZ. The optimized geometries and the adiabatic excitation energies of these states are in good agreement with experiments and previous calculations. The crossings and avoided crossings dis- played in the potential energy surfaces are expounded.

关键词： cross of PES, MRPT2. SO2 (sulfur dioxide).

Preparation and Characterization of Palladium Colloidal Nanoparticles by Thermal Decomposition of Palladium Acetate with Microwave Irradiation

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Journal of Materials Science & Technology 2005年第2期21卷 187-190页

作者： Yixian CHEN, Baolin HE and Hanfan lIU Hubei key laboratory for Catalysis and Material Science, University of South-Central for Nationalities, Wuhan 430074, China PClCC, State key laboratory of Polymer physics and Chemistry, institute of Chemistry, chinese academy of sciences, Beijing 100080, China lab. for Catalysis and Mat. Sci. Univ. of South-Central for Natl. Wuhan 430074 China lab. of Polymer Phys. and Chem. Inst. of Chem. Chinese Acad. of Sci. Beijing 100080 China

A series of solvent-stabilized palladium colloidal nanoparticles were prepared via thermal decomposition of palladium acetate methylisobutylketone (MIBK) solution in the presence of alkali and alcohol with microwave irradiation. The colloidal nanoparticles were characterized with TEM, XPS and XRD. The average diameters of nanoparticles increase from 30 to 40 nm with the increase in concentration of palladium acetate. TEM and XRD observation demonstrated that the palladium colloidal nanoparticles were clusters agglomerated from hundreds of smaller palladium crystallines with size of 3-4 nm. The influence of the concentrations of alkali and alcohol to the particle size was also discussed.

关键词： Thermal decomposition Microwave Palladium acetate Methylisobutylketone

Synthesis,characterization,and thermostability of bis(2.2.6,6-tetramethyl-3,5-heptanedionato)copper(Ⅱ)

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Rare Metals 2012年第4期31卷 343-349页

作者： ZHANG Teng,GU Hongwei,DING Fazhu,QU Fei,and DAI Shaotao key laboratory of Applied Superconductivity,{2. of Electrical Engineering,chinese academy of sciences,Beijing 100190,China key laboratory of Applied Superconductivity Institute of Electrical Engineering Chinese Academy of Sciences Beijing China

Owing to the adaptability to large scale processing,excellent composition control and film uniformity,the metal-organic chemical vapor deposition（MOCVD） technique is a promising process for high-temperature superconductor YBa;Cu;O;（YBCO） *** this technique,the evaporation characteristics and thermostability of adopted precursors in whole process will decide the quality and reproducible results of YBCO *** the present report,bis（2.2.6,6-tetramethyl-3,5-heptanedionato）copper（II）(Cu（TMHD）;) was synthesized by the interaction of copper acetate hydrate with TMHD in methanol solution,and its structure was identified by FTIR,1 H NMR,and EI-MS ***,thermal property and the kinetics of decomposition were systematically investigated by nonisothermal thermogravimetric analysis methods（TGA） at different heating rates in streams of N;,and the average apparent activation energy of evaporation process was evaluated by the Ozawa,Kissinger,and Friedman *** possible conversion function was estimated through the Coats-Redfern method to characterize the evaporation patterns and followed a phase boundary reaction mechanism by the contracting area equation with average activation energy of 85.1 kJ·mol;.

关键词： Cu(TMHD)_2 metal-organic chemical vapor deposition(MOCVD) synthesis thermostability

high-resolution photofragment translational spectro- scopy for the UV photodissociation of C_2._5I

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Science China Chemistry 2007年第4期50卷 476-482页

作者： BI WeiBin, XU Xiling, HUANG JianGou, xiao DaoQing & ZHU QiHe Beijing National laboratory for Molecular {2., State key laboratory of Molecular Reaction Dynamics, institute of Chemistry, chinese academy of sciences, Beijing 100080, China Beijing National laboratory for Molecular sciences State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing China

The photodissociation of ethyl iodide at 2.9.71, 2.1.73, 304.02.and 304.67 nm has been studied on our new mini-photofragment translational spectrometer with a total flight path of only 5 cm. Some vibra-tional peaks are firstly resolved in the TOF spectra of I*(2.1/2. and I(2.3/2. channels. These vibrational peaks are assigned to the excitation states (ν2.= 0, 1, 2.…) of the umbrella mode (ν2. 540 cm-1) of the photofragment C2.5, and the distribution of the vibrational states is obtained. The dissociation energy has been determined to be D0(C-I)=2.314 ± 0.03 eV. The energy partitioning of the available energy (Eavl=ET+Eint=ET+EV,R) calculated from our experimental data E int /E avl= 2..1% at 2.1.73 nm, 2..4% at 304.02.nm for the I* channel, and E int /E avl= 2..2. at 2.9.71 nm, 2..9% at 304.67 nm for the I channel, seem to be more reliable.

关键词： photofragment translational spectroscopy C_2._5I photodissociation vibrational state distribution energy partitioning dissociation energy

VISCOElASTIC BEHAVIOR OF THE NON-HOOKE DEFORMATION BEFORE YIElDING IN UNIAXIAl DRAWING OF AMORPHOUS POlY(ETHYlENE TEREPHTHAlATE)

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chinese Journal of Polymer Science 2001年第4期19卷 399-405页

作者： Zhen-hua Yuan De-yan Shen Ren-yuan Qian Polymer physics laboratory Center for Molecular Science, {2. of Chemistry chinese academy of sciences, Beijing 100080 China 中科院化学所高分子物理及化学国家重点实验室北京

Viscoelastic behavior of the non-Hooke deformation of amorphous PET film before yield was investigated in the temperature region 74-80.5 degreesC around the glass transition temperature. The film specimen was drawn to yield point followed by unloading to zero stress, then the residual deformation was held constant; while the subsequent evolution of the stress was recorded. An induction period was found in the course of stress evolution followed by a stress step-increase. The induction period decreases with increasing drawing temperature with an activation energy of 1.10 MJ/mol.K, which is attributed to the time needed for the relaxation of rubbery deformation through cooperative internal rotations. At temperatures lower than 74 degreesC, there is no stress increase or the induction period becomes too long to be observed. Thus the nature of anelasticity in the non-Hooke region before yielding is attributed to stress induced rubbery deformation. The experimental results are interpreted in terms of Perez' theological model of a series connected Hooks spring and a Voigt element consisting of a parallel connected elastic spring and a dashpot.

关键词： pre-yield deformation PET uniaxial drawing non-Hooke deformation viscoelasticity stress induced rubbery deformation

Propagation of interplanetary shock excited ultra low frequency (UlF) waves in magnetosphere-ionosphere-atmosphere——Multi-spacecraft “Cluster” and ground-based magnetometer observations

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Science China(Technological sciences) 2010年第9期53卷 2528-2534页

作者： WANG ChengRui1,2.ZONG QiuGang1,3 & WANG YongFu1 1 institute of Space physics and Applied Technology,Peking University,Beijing 100871,China 2.Sate {2. laboratory of Space Weather,chinese academy of sciences,Beijing 100190,China 3 Center for Atmospheric Research,600 Suffolk Street,University of Massachusetts lowell,MA 01854,USA institute of Space physics and Applied Technology Peking University Beijing China Sate key laboratory of Space Weather Chinese Academy of Sciences Beijing China Center for Atmospheric Research University of Massachusetts Lowell USA

The ultra low frequency (UlF) wave in magnetosphere can act as an important means for solar wind energy inward *** paper quantitatively analyzes the propagation process of the UlF wave triggered by the interplanetary shock propagating from inner magnetosphere equatorial plane along magnetic field lines to the top of the ionosphere and below ionosphere propagating process and establishes a relatively complete magnetosphere-ionosphere-atmosphere propagation model which can be used to study the relationship between the amplitude of the UlF waves triggered by the interplanetary shock wave in magnetospheric space and the magnetic effect caused by the UlF *** a comparison with recent observations,we found that: in the event during November 7,2.04 that an interplanetary shock wave interacted with the magnetosphere,Cluster satellites observed that electric field fluctuations and the band-pass filtered result of ground stations meridional component had similar *** with the geomagnetic measurement near the footprints,we found that the electric field disturbance in the magnetosphere spread along the ground magnetic field lines in the form of the UlF waves and changed into geomagnetic *** result reveals that the UlF wave is in contact with the ground geomagnetic *** UlF waves couple with ionized components in ionosphere and spread to the ground in the form of electromagnetic *** this research,we believe that the magnetosphere,ionosphere and ground magnetic effects caused by interplanetary shock wave are the same physical phenomena responding in different *** on the overall consideration of entire electromagnetic response to the interplanetary shock wave,we found that the correlation between ClUSTER multi-satellite observation and geomagnetic station observation is due to the UlF wave propagated in magnetosphere-ionosphere-atmosphere system,and we quantitatively interpreted this response process

关键词： ultra low frequency (UlF) wave magnetic storm ionosphere IRI model interplanetary shock

XMM-Newton observation of the eclipsing binary Algol

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Research in Astronomy and astrophysics 2011年第4期11卷 457-470页

作者： Xue-Juan Yang Fang-Jun lu Bemd Aschenbach li Chen Faculty of Materials Optoelectronics and Physics Xiangtan University Xiangtan 411105China particle astrophysics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Max-Planck-Institut fur Extraterrestrische Physik 85741 Garching Germany Department of Astronomy Beijing Normal University Beijing 100875 China

We present an XMM-Newton observation of the eclipsing binary Algol which contains an X-ray dark B8V primary and an X-ray bright K2.V secondary. The observation covered the optical secondary eclipse and captured an X-ray flare that was eclipsed by the B star. The XMM-Newton European Photon Imaging Camera and Reflection Grating Spectrometer spectra of Algol in its quiescent state are described by a two-temperature plasma model. The cool component has a temperature around 6.4× 106 K while that of the hot component ranges from 2.to 4.0× 107 K. Coronal abundances of C, N, O, Ne, Mg, Si and Fe were obtained for each component for both the quiescent and the flare phases, generally with upper limits for S and Ar, and upper limits for C, N, and O from the hot component. F-tests show that the abundances do not need to be different between the cool and the hot component and between the quiescent and the flare phase with the exception of Fe. Although the Fe abundance of the cool component remains constant at -0.14, the hot component shows an Fe abundance of -0.2., which increases to -0.44 during the flare. This increase is expected from the chromospheric evaporation model. The absorbing column density NH of the quiescent emission is 2.5 - 102. cm-2. while that of the flare-only emission is significantly lower and consistent with the column density of the interstellar medium. This observation substantiates earlier suggestions of the presence of X-ray absorbing material in the Algol system.

关键词： stars abundance -- star binaries eclipsing -- stars flare -- stars indi-vidual Algol

Using soil surface gray level to determine surface soil water content

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Science China Earth sciences 2010年第10期53卷 1527-1532页

作者： ZHU YuanJun1,2.WANG YunQiang1,2.& SHAO MingAn1,2.1 State key laboratory of Soil Erosion and Dryland Farming on loess Plateau,{2. of Soil and Water Conservation,Northwest A & F University,Yangling 712.00,China 2.{2. of Soil and Water Conservation,chinese academy of sciences & Ministry of Water Resources,Yangling 712.00,China State key laboratory of Soil Erosion and Dryland Farming on loess Plateau Institute of Soil and Water Conservation Northwest A & F University Yangling China institute of Soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resources Yangling China

How to determine surface soil water content(SWC) quickly and accurately is fundamental in studying eco-hydrological processes and their *** we use laboratory experiments to determine surface SWC using soil surface gray level(SGl) values.A negatively exponential relationship exists between SGl and SWC,i.e.,SGl increases with the decrease of *** can be estimated based on initial SGl value(surface gray level when SWC=0),SWC,and a surface roughness coefficient characterized by mean soil particle *** variation range of SGl was larger than that of SWC,indicating that changes in SWC were enhanced in SGl,and that SGl would thus be sensitive to changes in soil *** the 95% confidence level,SWC can be determined by using the relationship between SWC and SGl established by the *** determination of SWC has a {2. precision when SWC was between dry and saturated.

关键词： loess Plateau soil water remote sensing surface roughness