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Age-associated alternations in cardiac β-adrenergic receptor signaling

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Journal of Geriatric Cardiology 2005年第4期2卷 254-257页

作者： Jing MA, Shiwen WANG, Ruiping XIAO The Institute of Molecular Medicine & the Institute of cardiovascular science, peking {3., beijing 100871, china The Institute of Geriatric Cardiology, Chinese PLA General Hospital, beijing 100853. china Laboratory of cardiovascular science, Gerontology Research center, National Institute on Aging, Baltimore, MD 21224, USA The Institute of Molecular Medicine & the Institute of cardiovascular science Peking University Beijing 100871 China The Institute of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China Laboratory of cardiovascular science Gerontology Research Center National Institute on Aging Baltimore MD 21224 USA

During aging, cardiac contractile response to β-AR stimulation is decreased in humans and animal models. Recent studies demonstrate that the positive inotropic effects of both β1-AR and β2-AR stimulation are significantly decreased with *** is accompanied by decreases in both β-AR subtype densities and a reduction in membrane adenylyl cyclase activity. However,neither G protein-coupled receptor kinases (GRKs) nor inhibitory G proteins (Gi) appears to contribute to the age-associated reduction in the β-AR modulation of contraction. Thus, while both aging and chronic heart failure exhibit a diminution in cardiac β-AR responsiveness, only heart failure exhibits increased GRK-mediated desensitization ofβ-Ars and an upregulation of Gi proteins.

关键词： Nature adrenergic receptor signaling Age-associated alternations in cardiac

Investigating spatial distribution of tourist attractions’inlinks: A case study of three mountains

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science china(Technological sciences) 2010年第S1期53卷 126-133页

作者： ZHANG Yi 1,QI LiNa 2,YANG AnRan 1,SHI Lei 1 & XU Li 1 1 Institute of RS and GIS,peking university,beijing 100871,{3. 2 center for Recreation and Tourism Research,peking university,beijing 100871,{3. peking Univ Inst RS & GIS Beijing 100871 Peoples R China peking Univ Ctr Recreat & Tourism Res Beijing 100871 Peoples R China

In hyperlink analysis,most researchers focus on interpreting hyperlink counts,they seldom concern themselves enough about the significance of spatial distribution of *** this paper,we argue that not only can the inlink count to a tourist attraction’s official website reflect its attractiveness,but also the spatial distribution of its inlinks can reflect the distribution of its tourist source *** mountains in Anhui Province,china,are chosen for the case ***,the correlation between the spatial distributions of an attraction’s tourist source markets and its official website’s inlinks is ***,the tourism indexes such as the spatial concentration index(SCI)and the attraction radius(AR),which are calculated by inlinks,are compared to the real indexes based on tourist ***,the detailed discussion and analysis are presented and an improved model,which is used to calculate the distribution of inlinks,is proposed.

关键词： tourist attractiveness hyperlink analysis spatial distribution of hyperlinks tourist source market

The study of two-color excitation upconversion of Pr(0.5)Yb(3.:ZBLAN

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science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 169-177页

作者： CHEN Xiaobo1 & SONG Zengfu2 1. Applied Optics beijing Area Major Laboratory, Analysis and testing center, beijing Normal {3., beijing 100875, china 2. peking {3., Physics School, beijing 100871, china Applied Optics beijing Area Major Laboratory Analysis testing center Beijing Normal University Beijing 100875 China Physics School Peking University Beijing 100871 China

The excited state absorption upconversion of Pr(0.5)Yb(3.:ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 480.1, 519.0, 601.9 and 63..8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1G4(Pr3.)→1I6(Pr3.) and 1G4(Pr3.)→3.1(Pr3.)], the 789.0 nm upconver-sion excitation transition 1G4(Pr3.)→3.2(Pr3.), and the 803.7 nm upconversion excitation transition 3.6(Pr3.)→1D2(Pr3.). The upconversion excitation transition 1G4(Pr3.)→1I6(Pr3.) is strong because its oscillator strength f = 23.040×10?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3.:ZBLAN induced by one laser and one continuous normal light simultaneously.

关键词： upconversion volumetric three-dimensional display two-color excitation.

BATE curve in assessment of clinical utility of predictive biomarkers

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science china Mathematics 2012年第8期55卷 1529-1552页

作者： ZHOU XiaoHua 1,2,3.& MA YunBei 4,5 1 Northwest HSR&D center of Excellence,VA Puget Sound health Care System,Seattle,WA 98198,USA 2 Department of Biostatistics,university of Washington,Seattle,WA 98198,USA 3.{3. International center for Mathematical Research,peking university,{3. 100871,china 4 Department of Operations Research and Financial Engineering,Princeton university,Princeton,NJ 08540,USA 5 School of Statisitcs,Southwest university of Finance and Economics,Chengdu 61113.,china 1. Northwest HSR&D center of Excellence VA Puget Sound Health Care System Seattle WA 98198 USA2. Department of Biostatistics University of Washington Seattle WA 98198 USA3. Beijing International Center for Mathematical Research Peking University Beijing 100871 China4. Department of Operations Research and Financial Engineering Princeton University Princeton NJ 08540 USA5. School of Statisitcs Southwest University of Finance and Economics Chengdu 611130 China

In this paper, for time-to-event data, we propose a new statistical framework for casual inference in evaluating clinical utility of predictive biomarkers and in selecting an optimal treatment for a particular patient. This new casual framework is based on a new concept, called Biomarker Adjusted Treatment Effect （BATE） curve. The BATE curve can be used for assessing clinical utility of a predictive biomarker, for designing a subsequent confirmation trial, and for guiding clinical practice. We then propose semi-p^rametric methods for estimating the BATE curves of biomarkers and establish asymptotic results of the proposed estimators for the BATE curves. We also conduct extensive simulation studies to evaluate finite-sample properties of the proposed estimation methods. Finally, we illustrate the application of the proposed method in a real-world data set.

关键词： predictive biomarker cutoff points interaction BATE curve time-to-event outcome

Flux of dimethylsulfide in the Jiaozhou Bay,china

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Journal of Environmental sciences 1997年第1期9卷 80-85页

作者： Hu Min Tang Xiaoyan center of Environmental sciences,peking {3.,beijing 100871,chinaLi Jinlong Yu Zhongju Department of Technical Physics,peking {3.,beijing 100871,china center of Environmental sciences Peking University Beijing 100871 China Department of Technical Physics Peking University Beijing 100871 China

Seasonal measurements of dimethylsulfide(DMS)in surface waters were carried out during 1993.1994 in the Jiaozhou Bay.A seasonal variation is observed for DMS concentrations in seawater,ranging from 0.6 to 8.97 nmol S/L with the highest values in spring.A factor of 4 was measured for DMS concentrations with mean concentrations of 5.85 nmol S/L or 6.58 nmol S/L in spring and 1.40nmol S/L in winter.A sea-to-air flux of DMS also showed a seasonal variation.

关键词： dimethyl sulfide flux seawater atmosphere.

Mechanism of Calcitonin Gene-related Peptide Modulating Apoptosis of Vascular Smooth Muscle Cells

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Mechanism of Calcitonin Gene-related Peptide Modulating Apop...

FURTHER EVIDENCE FOR FA centerS IN BaFCL:Eu^(2+) CRYSTAL

2002全国青年药理学英文学术会议

作者： WANG Wang, WANG Xian (Department of Physiology, health science center, {3. university, beijing, 100083)

AIM: Atherosclerosis (AS) is one of the major threatens of the health and life of human being. Accumulating data have supported the idea that the pathogenesis of AS includes a set of inflammatory and immune responses. The migration, proliferation and apoptosis of smooth muscle cells (SMC) also play an important role. Calcitonin gene-related peptide (CGRP) is a neuropeptide with potent vasodilatory effect. CGRP and its receptors are widely expressed throughout the cardiovascular system. Recently, more and more vasodilators have been found to have antiproliferative effects on SMC. Our previous data

关键词： Calcitonin Gene-related Peptide /Vascular Smooth Muscle Cells /Apoptosis

来源： cnki会议评论

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cnki会议

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Chinese Chemical Letters 1993年第9期4卷 817-820页

作者： Wei CHEN Department of Materials Physics,beijing university of science and Technology,beijing 100083Mian Zeng SU Department of Chemistry,peking university,beijing 100871

The formation of color centers in BaFCl:Eu^(2+) crystal is studied in more de- tail and further evidence for FA centers in BaFCl:Eu^(2+)is *** creation of color centers in BaFCl:Eu^(2+)may be devided into three *** long time X-irradiation be- yond stage 1,the concentration of FA centers depends linearly on the nth(n=1,2 or 3. power of F center *** under short time X-irradiation within stage 1,the concentration dependence of FA centers on F center is *** centers are easier to create than complex *** mechanisms for color centers formation in BaFCl:Eu^(2+) are also proposed and discussed.

关键词： FA FURTHER EVIDENCE FOR FA centerS IN BaFCL CRYSTAL

The Variational Lyapunov Method and Stability for Impulsive Delay Differential Systems

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Journal of Mathematical Research and Exposition 2010年第1期30卷 67-77页

作者： Kai En LIU1,2, Guo Wei YANG3.1. School of Mathematics, Qingdao university, Shandong 266071, P. R. china 2. center for Systems and Control, College of Engineering, {3. university, beijing 100871, P. R. china 3. School of Automation Engineering, Qingdao university, Shandong 266071, P. R. china School of Mathematics Qingdao University Shandong P.R.China 266071 School of Automation Engineering Qingdao University Shandong P.R.China 266071

By using the variational Lyapunov method and Razumikhin technique, the stability criteria in terms of two measures for impulsive delay differential systems are established. The known results are generalized and improv... 详细信息

关键词： impulsive delay differential system stability variational Lyapunov method Razumikhin technique two measures.

The correlation of multi-angle thermal infrared data and the choice of optimal view angles

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science china Earth sciences 2004年第6期47卷 570-576页

作者： FAN Wenjie1 & XU Xiru1,2 1.Institute of Remote Sensing and GIS of peking university,beijing 100871,{3. 2.center of Remote Sensing and GIS of beijing Normal university,beijing 100875,{3. 1. Institute of Remote Sensing and GIS of peking university 100871 Beijing China 2. center of Remote Sensing and GIS of beijing Normal university 100875 Beijing China

Based on the matrix formula of thermal infrared radiant system, the components temperature can be retrieved by the inversive matrix. Around the stability problem of retrieved result, the research work we did was focused on (i) the correlation of (wk,j) which is the key to affect the retrieval accuracy, (ii) a general method which can help us find the number of retrievable parameters and evaluate the retrieval error before its performance, (iii) the choice of “optimal viewing angle group” based on the formula of absolute error propagation. The row winter wheat field was chosen as an example. The results can provide a theoretical basis for multi-angle thermal infrared remote sensing and components temperature retrieval.

关键词： components temperature retrieval, correlation, number of retrievable parameters, optimal viewing angle group.