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Updating verbal and visuospatial working memory: Are the processes parallel?

Chinese Science Bulletin 2008年第14期53卷 2175-2185页

作者： YUE ZhenZhu1,2, ZHANG Ming3,4 & ZHOU XiaoLin1 1 department of psychology, Peking university, Beijing 100871, china 2 Biological psychology and Neuropsychology, university of Hamburg, Von-Melle-Park 11, 20146 Hamburg, Germany 3 department of psychology, northeast normal university, changchun 130024, china.4 key laboratory for applied statistics of moe, northeast normal university, changchun 130024, china department of psychology Peking University Beijing China Biological psychology and Neuropsychology University of Hamburg Hamburg Germany department of psychology Northeast Normal University Changchun China key laboratory for applied statistics of moe Northeast Normal University Changchun China

The current study compared the processes of updating verbal and visuospatial working memory (WM) and examined the roles of central executive and slave systems in working memory updating tasks, by changing the number of items updated simultaneously to manipulate the load on central executive. Ex- periment 1 used the verbal WM updating task, and the results validated the efficiency of the paradigm to manipulate the load on central executive. Experiment 2 employed the verbal WM updating task, with the articulatory suppression task to interfere with the phonological loop. The results supported the study by Morris and Jones, revealing that the central executive system played an important role in the updating component of verbal WM, while the phonological loop was responsible for the serial recall component. Experiment 3 employed the visuospatial WM updating task, with the spatial tapping task to interfere with the visuospatial sketchpad. The results suggested that the visuospatial sketchpad and the central execu- tive together dealt with the updating component, while the visuospatial sketchpad was responsible for the serial recall component by itself. These results are consistent with the findings that visuospatial sketch- pad has close links with central executive, while the phonological loop is separated from the central ex- ecutive. It suggests that updating visuospatial and verbal WM are not two parallel processes.

关键词：记忆储存工作记忆中枢神经视觉性

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Revisit of Sheppard corrections in linear regression

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Science china Mathematics 2010年第6期53卷 1435-1451页

作者： LIU TianQing1,ZHANG BaoXue1,HU GuoRong1 & BAI ZhiDong1,2,1key laboratory for applied statistics of moe and School of Mathematics and statistics,northeast normal university,changchun 130024,china 2department of statistics and applied Probability,National university of Singapore,Singapore 117543,Singapore key laboratory for applied statistics of moe and School of Mathematics and statistics Northeast Normal University Changchun China department of statistics and applied Probability National University of Singapore Singapore Singapore

Dempster and Rubin(D&R) in their JRSSB paper considered the statistical error caused by data rounding in a linear regression model and compared the Sheppard correction,BRB correction and the ordinary LSE by *** asymptotic results when the rounding scale tends to 0 were also *** a previous research,we found that the ordinary sample variance of rounded data from normal populations is always inconsistent while the sample mean of rounded data is consistent if and only if the true mean is a multiple of the half rounding *** the light of these results,in this paper we further investigate the rounding errors in linear *** notice that these results form the basic reasons that the Sheppard corrections perform better than other methods in D&R examples and their conclusion in general cases is *** in which the Sheppard correction works worse than the BRB correction are also ***,we propose a new approach to estimate the parameters,called "two-stage estimator",and establish the consistency and asymptotic normality of the new estimators.

关键词： asymptotic normality consistency linear regression model rounded data two-stage estimates

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Efficient estimation for additive hazards regression with bivariate current status data

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Science china Mathematics 2012年第4期55卷 763-774页

作者： TONG XingWei 1,,HU Tao 2 & SUN JianGuo 3,4 1 School of Mathematical Sciences,Beijing normal university,Beijing 100875,china 2 School of Mathematical Sciences,Capital normal university,Beijing 100048,china 3 School of Mathematics,Jilin university,changchun 130012,china.4 department of statistics,university of Missouri,Columbia,MO 65211,USA School of Mathematical Sciences Beijing Normal University Beijing China School of Mathematical Sciences Capital Normal University Beijing China School of Mathematics Jilin University Changchun China department of statistics University of Missouri Columbia USA

This paper discusses efficient estimation for the additive hazards regression model when only bivariate current status data are available. Current status data occur in many fields including demographical studies and tumorigenicity experiments （Keiding, 1991; Sun, 2006） and several approaches have been proposed for the additive hazards model with univariate current status data （Linet M., 1998; Martinussen and Scheike, 2002）. For bivariate data, in addition to facing the same problems as those with univariate data, one needs to deal with the association or correlation between two related failure time variables of interest. For this, we employ the copula model and an efficient estimation procedure is developed for inference. Simulation studies are performed to evaluate the proposed estimates and suggest that the approach works well in practical situations. An illustrative example is provided.

关键词： bivariate current status data copula model counting processes efficient estimation joint survivalfunction

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THE　CRYSTAL　STRUCTURE　AND　STEREOCHEMISTRY　OF　BENZOYL　KETENE　O，S　ETHYLENE　ACETAL

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Chinese Chemical Letters 1994年第12期5卷 1031-1032页

作者： Shu Jia ZHANG Ji Geng TANG Qun LIU(department of Chemistry, northeast normal university.changchun, 130024)Yan XING Yong Hua LIN(changchun Institute or applied Chemistry, Academy of Science,)

The crystal structure or the title compound 4, synthesized from benzoyl ketene dimethylthio acetal 3 and mercaptoethanol under basic condition. shows it has Z-configuration. This result supports that the formation of ...

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Analysis of Low-polar Ginsenosides in Steamed Panax Ginseng at High-temperature by HPLC-ESI-MS/MS

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Chemical Research in Chinese Universities 2012年第1期28卷 31-36页

作者： ZHANG Yu-chi1,2, PI Zi-feng1, LIU Chun-ming2, SONG Feng-rui1, LIU Zhi-qiang1 and LIU Shu-ying1 1. changchun Center of Mass Spectrometry, changchun Institute of applied Chemistry, Chinese Academy of Sciences, changchun 130022, P. R. china 2. Central laboratory, changchun normal university, changchun 130032, P. R. china changchun Center of Mass Spectrometry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 Central laboratory Changchun Normal University Changchun 130032

A high performance liquid chromatography coupled with electrospray ionization-tandem mass spectrome try（HPLC-ESI-MS/MS） method was developed for the analysis and identification of ginsenosides in the extracts of raw Panax ginseng（RPG） and steamed Panax ginseng at high temperatures（SPGHT）. A total of 25 ginsenosides were extracted include of which 10 low-polar ginsenosides, such as ginsenosides F4, Rk3, Rh4, 20S-Rg3, 20R-Rg3 and so on, were identified according to their HPLC retention time and MS/MS data. The results indicated that the low polar ginsenosides were seldom found in RPG. For the exploration of the transformation pattern of the ginsenosides in steam processing, the standards of ginsenosides Re, Rg1, Rb1, Rc, Rb2, Rb3 and Rd were selected and hydrolyzed at a temperature of 120 oC. The results show that these polar ginsenosides can be converted to low-polar ginsenosides such as Rg2, Rg6, F4, Rk3 and Rg5 by hydrolyzing the sugar chains.

关键词： Ginsenoside Hydrolysis Steamed Panax ginseng High performance liquid chromatography coupled withelectrospray ionization-tandem mass spectrometry(HPLC-ESI-MS/MS)

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A novel Cu(I) complex based organic ultraviolet optical sensor

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Optoelectronics Letters 2009年第1期5卷 14-17页

作者：车广波刘春波徐占林李文连孔治国王庆伟 department of Chemistry Jilin Normal University Stata key laboratory of the Excited States Process Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences Institute of applied Chemistry Jilin Normal University

A novel Cu(I) complex with the formula of [Cu(DPEphos)(Dicnq)]BF4(CuDD) was synthesized and characterized by X-ray single crystal diffraction method,in which DPEphos and Dicnq denote bis[2-(diphenylphosphino)phenyl]ether and 6,7-Dicyanodipyrido[2,2-d:2 ,3 -f] quinoxaline,*** ultraviolet optical sensor based on photovoltaic diode is fabricated by using CuDD as an electron acceptor and 4,4′,4″-tris-(2-methylphenyl phenylamino) triphenylamine(m-MTDATA) as an electron *** sensor is sensit...

关键词： Conversion efficiency Ethers Light Open circuit voltage Optical sensors Single crystals

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Saddlepoint approximations for studentized compound Poisson sums with no moment conditions in audit sampling

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Science china Mathematics 2010年第12期53卷 3131-3138页

作者： ZHOU GuoLiang 1 & ZHOU Wang 2, 1 Institute of Accounting and Finance, Shanghai university of Finance and Economics, Shanghai 200433, china 2 department of statistics and applied Probability, National university of Singapore, Singapore 117546, Singapore Institute of Accounting and Finance Shanghai University of Finance and Economics Shanghai China department of statistics and applied Probability National University of Singapore Singapore Singapore

Saddlepoint approximations for the studentized compound Poisson sums with no moment conditions in audit sampling are derived. This result not only provides a very accurate approximation for studentized compound Poisson sums, but also can be applied much more widely in statistical inference of the error amount in an audit population of accounts to check the validity of financial statements of a firm. Some numerical illustrations and comparison with the normal approximation method are presented.

关键词： saddlepoint approximation Laplace approximation self-normalized compound Poisson sum stu- dentized compound Poisson sum

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CH2,NH,and O heteroatom substitution effects on the electronic,optical,and charge transport properties of a 2,1,3-benzothiadiazole-based derivative:Insights from theory

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Science china Chemistry 2012年第7期 1381-1386页

作者： HU Bo1,2*,YAO Chan1,2,WANG QingWei1,2,ZHANG Hao3 & YU JianKang3,4 1Faculty of Chemistry,Jilin normal university,Siping 136000,china 2key laboratory of Preparation and Applications of Environmental Friendly Materials(Jilin normal university),Ministry of Education,Siping 136000,china 3State key laboratory of Theoretical and Computational Chemistry,Jilin university,changchun 130023,china.4Institute of applied Physics and Technology,Foundation department of Liaoning Technical university,Huludao 123000,china

A set of CH2-,NH-,and O-substituted 2,1,3-benzothiadiazole(BTD)-based derivatives have been investigated theoretically in order to explore their electronic,optical,and charge transport *** calculation results show that the electronic and optical properties of the pristine molecule can be easily tuned through changing the S substituent in the central aromatic *** on the calculated maximum emission wavelength,we predict that CH2-,NH-,and O-substituted BTD-based derivatives could be used as red,green,and orange light-emitting materials,*** CH2-,NH-or O-substitution,the oscillator strengths of the emission spectra are enhanced with respect to that of the pristine molecule,implying that these compounds have larger fluorescence ***,it can be deduced that CH2-,NH-,and O-substituted BTD-based derivatives may act as hole transport materials in organic light-emitting diodes.

关键词： organic light-emitting devices(OLEDs) 2 1 3-benzothiadiazole electronic properties optical properties reorganization energy

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Influence of Metal Cations and Cholesterol on Lipid-amphotericin Membrane

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Chemical Research in Chinese Universities 2017年第3期33卷 447-453页

作者： WANG Juan SUN Runguang HAO changchun LI Tuo TIAN Yuan ZHANG Lei Engineering Technology Research Center of Controllable Neutron Source and Its Application Department of Applied Statistics and Science Xijing University Xi 'an 710123 P. R. China laboratory of Biophysics and Biomedicine College of Physics and Information Technology Shaanxi Normal University Xi'an 710119 P. R. China

Amphotericin B（AmB） has been widely used in antifungal therapy. AraB molecules combine with cholesterol to form pores that can be toxic to human cells, thus greatly limiting its clinical application. The interaction between Arab and the cell membrane may be influenced by potassimn, sodium and calcium ions. Lq this study, the bilayer in large unilamellar lipid-drug liposomes with or without cholesterol was employed as a model membrane. N-（7-Nitrobenz-2-oxa-1,3-diazol-4-yl）-1,2-dipalmitoyl-sn-glycero-3-phosphoetheanolamine（N-BD-PE） and 1-palmi-toyl-2-[6（7-nitrobenz-2-oxa-1,3-diazol-4-yl）aminodoclecanoyl]-sn-glysero-3-phosphocholine（6-NBD-PC） are two kinds of fluorescent lipid probes, and the NBD group is attached to the polar lipid headgroup in the former, but to the sn-2 fatty acyl chain in the latter. The effect of these metal cations on the lipid-drug membrane was monitored by red edge excitation shift（REES）, fluorescence polarization, and the fluorescence lifetime of lipid probes in hydrophilic and hydrophobic areas of the membrane. These ions have different effects on the lipid-AraB membrane. Cholesterol can strengthen the packing ability of the membrane, which is influenced differently by potassium, sodium and calcium ions. Moreover, the influence of these ions on the membrane may be relative to the method of ion transportation through the membrane. This study is significant to understand the reduction of AraB＇s cellular toxicity.

关键词： Amphotericin B NBD-labeled lipid Red edge excitation shift Metal cation Fluorescence polarization

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THE CORNER LAYER SOLUTION TO ROBIN PROBLEM FOR REACTION DIFFUSION EQUATION

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Annals of Differential Equations 2012年第2期28卷 132-136页

作者： Lihua Chen (Dept. of Math. and Computer Science, Fuqing Branch of Fujian normal university, Fuqing 350300, Fujian) Zhaohui Wen (Institute of applied Math., School of statistics and applied Mathematics, Anhui university of Finance and Economics, Bengbu 233030, Anhui) Cheng Ouyang (Faculty of Science, Huzhou Teacher College, Huzhou 313000, Zhejiang) Jiaqi Mo (Dept. of Math., Anhui normal university, Wuhu 241003, Anhui)

A class of Robin boundary value problem for reaction diffusion equation is considered. Under suitable conditions, using the theory of differential inequalities the existence and asymptotic behavior of the corner layer... 详细信息

关键词： corner layer asymptotic solution Robin problem

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