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Cilia and ciliopathies:From Chlamydomonas and beyond

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Science china(Life Sciences) 2008年第6期51卷 479-486页

作者： PAN JunMin department of Biological Sciences and Biotechnology, Tsinghua university, beijing 100084, china department of Biological Sciences and Biotechnology Tsinghua University Beijing China

The biological function of motile cilia/flagella has long been recognized. The non-motile primary cilium, once regarded as a vestigial organelle, however, has been found recently to play unexpected roles in mammalian physiology and development. Defects in cilia have profound impact on human health. Diseases related to cilia, collectively called ciliopathies include male infertility, primary cilia dyskinesia, renal cyst formation, blindness, polydactyly, obesity, hypertension, and even mental retardation. Our current understanding of cilia and ciliopathies has been fueled by basic research employing various model organisms including Chlamydomonas, a unicellular green alga. This review article provides a general introduction to the cell biology of cilia and an overview of various cilia-related diseases.

关键词： Chlamydomonas cilia flagellla human disease ciliopathy

Interaction between hydrogen sulfide/cystathionine γ-lyase and carbon monoxide/heme oxygenase pathways in aortic smooth muscle cells

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Acta Pharmacologica Sinica 2006年第12期27卷 1561-1566页

作者： Hong-fang JIN~2 Jun-bao DU~(2,4)Xiao-hui LI~2 Yan-fei WANG~2 Yin-fang LIANG~2 Chao-shu TANG~3 2 department of Pediatrics,Peking university First Hospital,beijing 100034,china 3 Institute of Cardiovascular Research,Peking university First Hospital,beijing 100034,china department of Pediatrics Peking University First Hospital Beijing China Institute of Cardiovascular Research Peking University First Hospital Beijing China

Aim:To investigate the interaction between hydrogen sulfide（H2S）/cystathion-ine γ-lyase（CSE）and carbon monoxide（CO）/heme oxygenase（HO）pathways inaortic smooth muscle cells（ASMC）.Methods:The ASMCs were divided into thefollowing groups:（1）the control group;（2）the zinc protoporphyrin（ZnPP）20μmol/L group;（3）the propargylglycine（PPG）2 mmol/L,4 mmol/L and 10 mmol/Lgroups;and（4）the sodium hydrosulfide（NariS）1×10-5mol/L,1×10-4mol/L and1×10-3mol/L *** of the groups was further divided into 6h,12h,18hand 24h *** CO level,represented by carboxyhemoglobin（HbCO）content was measured using a spectrophotometric method and H2S content wasdetected by a sensitive electrode *** and HO-1 expressions were de-tected by Western ***:The H2S content in the medium and CSEexpression by ASMC were markedly increased by ZnPP compared with the con-trol *** content in the medium and HO-1 expression by the ASMCstarted strengthening following 24h treatment with PPG at 2 mmol/L,but werefurther strengthened following 18h and 24h treatment with PPG at 4 mmol/Lcompared with the controls（P2h ***,NariS at 1×10-5mol/L and 1×10-4mol/Ldecreased the HbCO level in the medium and HO-1 expression by the ASMC after6h and 12h treatment,while NariS at 1×10-3mol/L decreased them at all timepoints of the ***:The results suggested that endogenousCO/HO and H2S/CSE pathways inhibited each other in ASMC under physiologi-cal conditions.

关键词： hydrogen sulfide cystathionine γ-lyase carbon monoxide heme oxygenase

Comparison of fractal measures

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Science china Mathematics 2005年第11期48卷 1545-1553页

作者： QU Yanhui,WEN Shengyou & WEN Zhiying department of Mathematics,Tsinghua university,beijing 100084,china department of Mathematics,Hubei university, Wuhan 430062, china department of Mathematics Tsinghua University Beijing China department of Mathematics Hubei University Wuhan China

In this paper, the relationship between the s-dimensional Hausdorff measures and the g-measures in Rd is discussed, where g is a gauge function which is equivalent to ts and 0 < s≤d. It shows that if s=d, then Hg = c... 详细信息

In this paper, the relationship between the s-dimensional Hausdorff measures and the g-measures in Rd is discussed, where g is a gauge function which is equivalent to ts and 0 2Cd and Pg = c3Pd on Rd, where constants c1, c2 and c3 are determined by where Wg, Cg and Pg are the g-Hausdorff, g-central Hausdorff and g-packing measures on Rd respectively. In the case 02Cs|F and Pg|F = c3Ps|F, where the constants c1, c2 and c3 depend not only on g and s, but also on F. A criterion is presented for judging whether an s-set has the above properties.

关键词： gauge function Hausdorff measure central Hausdorff measure packing measure.

LARGE DEFLECTION THEORY OF NANOBEAMS

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Acta Mechanica Solida Sinica 2010年第5期23卷 394-399页

作者： Dujuan Zeng Quanshui Zheng 1(department of Engineering Mechanics,Tsinghua university,beijing 100084,china) department of Engineering Mechanics Tsinghua University Beijing China

One-dimensional nanostructured materials are often used as beams in many applications such as ultrahigh-frequency resonators and ultrasensitive sensors. Compared with usual macroscopic beams, nanobeams have much higher surface/volume ratios so that their surface energies may play a significant role. Besides, they often bear large deflections due to their typically large slenderness ratios and larger elastic ranges. There is, however, lack of a theory that takes into account of both the above two features owned by nanobeams. In this paper, we present such a theory and give applied examples to show that surface energy and large deflection may individually or jointly have notable effects.

关键词： nanobeam surface energy large deflection

Tissue-specific expression of glutathione S-transferases induced by 2-tridecanone or quercetin in cotton bollworms, Helicoverpa armigera (Hübner)

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Progress in Natural Science:Materials International 2005年第11期15卷 988-992页

作者： TANG Fang, LIANG Pei and GAO Xiwu (department of Entomology, china Agricultural university, beijing 100094, china) department of Entomology China Agricultural University Beijing 100094 China

The tissue-specific expression of glutathione S-transferases (GSTs) in the cotton bollworm and the expression level induced by 2-tridecanone and quercetin were examined using the methods of biochemistry and the quantitative PCR. The relative expression level of GST mRNA was unanimous with the GSTs activity conjugaging with 1-chloro-2, 4-dimitro-benzene (CDNB) in fat bodies, midguts, heads and integuments of cotton bollworms. The GSTs activity in fat bodies was the highest, then midguts, heads and integuments in turn, which was in consistent with the relative expression level of GST mRNA. The specific activity of GSTs and the relative expression level of GST mRNA could be significantly induced by 2-tridecanone and quercetin, and after the induction the order of the GSTs activity and the relative expression level of GST mRNA in the above four tissues in cotton bollworms was not different from the control. The induction of GSTs by 2-tridecanone was stronger than by quercetin in all four tissues, which was in accordance with the relative expression level of GST mRNA. It suggested that the increase of GSTs activity induced by plant allelochemicals was associated with the elevated expression of GST mRNA in cotton bollworms.

关键词： Helicoverpa armigera glutathione S-transferase tissue-specific expression plant allelochemicals.

A stochastic method for convective storm identification,tracking and nowcasting

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Progress in Natural Science:Materials International 2008年第12期18卷 1557-1563页

作者： Lei Han~(a,b) Shengxue Fu~a Guang Yang~c Hongqing Wang~b Yongguang Zheng~d Yingjing Lin~b a college of Information Science and Engineering.Ocean university of china,Qingdao 266101,china b department of Atmospheric Science,Peking university,beijing 100871,china c department of Probability and Statistics,Peking university,beijing 100871,china d National Meteorological Center,beijing 100081,china college of Information Science and Engineering Ocean University of China Qingdao 266101 China department of Atmospheric Science Peking University Beijing 100871 China department of Probability and Statistics Peking University Beijing 100871 China National Meteorological Center Beijing 100081 China

The convective storm identification,tracking and nowcasting method is one of the important nowcasting methodologies against severe convective *** severe convective cases,such as storm shape or rapid velocity changes,existing methods are apt to provide unsatisfied storm identification,tracking and nowcasting *** overcome these difficulties,this paper proposes a novel approach to identify,track and short-term forecast (nowcast) of convective storms.A mathematical morphology-based storm identification method is adopted which can identify storm cells accurately in a cluster of *** for the difficult tracking problem,sequential Monte Carlo (SMC) method is utilized to simplify the tracking *** is not only inherently suitable for handling complicated splits and mergers, but also capable of handling the case of storm-missing *** order to provide more accurate forecast of a storm position,this method takes the advantages of the cross-correlation *** qualitative and quantitative evaluations show the efficiency and robustness of the proposed approach.

关键词： Convective storm Doppler radar Nowcasting

Right prefrontal laterality of Chinese boys during a Chinese high conflict Stroop task measured by multi-channel near-infrared spectroscopy imaging

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Progress in Natural Science:Materials International 2007年第9期17卷 1023-1028页

作者： Liu Jiacheng1,Bai Jing1,Peng Miao2,Fan Xiaofei1 and Guo Qiyong3(1.department of Biomedical Engineering,Tsinghua university,beijing 100084,china 2.department of Electroneurophysiology,the Sixth Hospital of Peking university,beijing 100085,china 3.department of Radiology,The Second Hospital of china Medical university,Shenyang 110003,china) department of Biomedical Engineering Tsinghua University Beijing 100084 China department of Electroneurophysiology Sixth Hospital of Peking University Beijing 100085 China department of Radiology Second Hospital of China Medical University Shenyang 110003 China

Some studies have shown that native Chinese speakers have different laterality in matched Stroop tasks from native English ***,many imaging data,which show left laterality of English-matched Stroop interference,have been *** a few functional imaging studies have been conducted to investigate the phenomenon of the Chinese version of Stroop *** this study,functional activity in the lateral prefrontal cortex of a group of normal Chinese boys with functional near-infrared imaging during a Stroop color-word task was measured to show different Stroop interferences in the prefrontal *** results show obvious fluctuation of the cerebral blood volume in the right prefrontal cortex in all boys,which agrees with the finding of previous studies,that is,Chinese native boys have right laterality in their brain when the Chinese version of Stroop color-word task is applied.

关键词： laterality Stroop effect prefrontal cortex near-infrared

Estimating forest aboveground biomass using HJ-1 Satellite CCD and ICESat GLAS waveform data

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Science china Earth Sciences 2010年第S1期53卷 16-25页

作者： GUO ZhiFeng1,CHI Hong1,2 & SUN GuoQing1,3 1State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal university,Institute of Remote Sensing Applications,Chinese Academy of Sciences,beijing 100101,china 2Graduate university of Chinese Academy of Sciences,beijing 100049,china 3department of Geography university of Maryland,college Park,MD 20742,USA State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of Sciences Beijing China department of Geography university of Maryland College Park USA

The ecosystem in northeastern china and the Russian Far East is a hotspot of scientific research into the global carbon *** aboveground biomass(AGB) is an important component in the land surface carbon *** this study,using forest inventory data and forest distribution data,the AGB was estimated for forest in Daxinganlin in northeastern china by combining charge-coupled device(CCD) data from the Small Satellite for Disaster and Environment Monitoring and Forecast(HJ-1) and Geoscience Laser Altimeter System(GLAS) waveform data from the Ice,Cloud and land Elevation Satellite(ICESat).The forest AGB prediction models were separately developed for different forest types in the research area at GLAS footprint level from GLAS waveform parameters and field survey plot biomass in the Changqing(CQ) Forest Center,which was calculated from forest inventory *** resulted statistical regression models have a R2=0.68 for conifer and R2=0.71 for broadleaf *** models were used to estimate biomass for all GLAS footprints of forest located in the study *** GLAS footprint biomass coupled with various spectral reflectivity parameters and vegetation indices derived from HJ-1 satellite CCD data were used in multiple regression analyses to establish biomass prediction models(R2=0.55 and R2=0.52 for needle and broadleaf respectively).Then the models were used to produce a forest AGB map for the whole study area using the HJ-1 *** data obtained from forest inventory data of the Zhuanglin(ZL) Forest Center were used as independent field measurements to validate the AGB estimated from HJ-1 CCD data(R2=0.71).About 80% of biomass samples had an error less than 20 t ha-1,and the mean error of all validation samples is 5.74 t *** pixel-level biomass map was then stratified into different biomass levels to illustrate the AGB spatial distribution pattern in this *** was found that HJ-1 wide-swath data and GLAS waveform data can be combined to estim

关键词： Disaster and Environment Monitoring and Forecast Satellite ICESat GLAS waveform boreal forest forest aboveground biomass multiple linear regression

Experimental measurement of growth patterns on fossil corals:Secular variation in ancient Earth-Sun distances

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Chinese Science Bulletin 2010年第35期55卷 4010-4017页

作者： ZHANG WeiJia1,3,4,LI ZhengBin2,3 & LEI Yang1 1 department of Physics,Peking university,beijing 100871,china 2 department of Electrical Engineering and Computer Science,Peking university,beijing 100871,china 3 State Key Laboratory of Advanced Optical Communication Systems & Networks,Peking university,beijing 100871,china 4 Committee of Yuanpei Honors Program,Peking university,beijing 100871,china department of Physics Peking University Beijing China State Key Laboratory of Advanced Optical Communication Systems & Networks Peking University Beijing China Committee of Yuanpei Honors Program Peking University Beijing China department of Electrical Engineering and Computer Science Peking University Beijing China

In recent years,much attention has been given to the increase in the Earth-Sun distance,with the modern rate reported as 5-15 m/cy on the basis of astronomical ***,traditional methods cannot measure the ancient leaving rates,so a myriad of research attempting to provide explanations were met with unmatched *** this paper we consider that the growth patterns on fossils could reflect the ancient Earth-Sun *** mechanical analysis of both the Earth-Sun and Earth-Moon systems,these patterns confirmed an increase in the Earth-Sun *** a large number of well-preserved specimens and new technology available,both the modern and ancient leaving rates could be measured with high precision,and it was found that the Earth has been leaving the Sun over the past 0.53 billion *** Earth's semi-major axis was 146 million kilometers at the beginning of the Phanerozoic Eon,equating to 97.6% of its current *** modern leaving rates are 5-14 m/cy,whereas the ancient rates were much *** results indicate a special expansion with an average expansion coefficient of 0.57H0 and deceleration in the form of Hubble *** the basis of experimental results,the Earth's semi-major axis could be represented by a simple formula that matches fossil measurements.

关键词：地球太阳古代距离生长模式实验石珊瑚量化