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Polycomb-group （Pc-G） Proteins Control Seed Development in Arabidopsis thaliana L.

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Journal of Integrative Plant Biology 2007年第1期49卷 52-59页

作者： Xiao-xue wang li-Geng Ma National Institute of Biological Sciences Beijing 102206 China

Polycomb-group （Pc-G） proteins repress their target gene expression by assemble complexes in Drosophila and mammals. Three groups of Pc-G genes, controlling seed development, flower development and vernalization response, have been identified in Arabidopsis （Arabidopsis thaliana L.）. MEDEA （MEA）, FERTIliZATION INDEPENDENT SEED2 （FIS2）, and FERTIliZATION INDEPENDENT ENDOSPERM （FIE） are Pc-G genes in Arabidopsis. Their functions in seed development have been extensively explored. The advanced findings of molecular mechanism on how MEA, FIS2 and FIE control seed development in Arabidopsis are reviewed in this paper.

关键词： Arabidopsis FIS1/MEA FIS2 FIS3/FIE Pc-G genes

Development of the fast arcing protection for ECRH system on the HL-2A tokamak

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核聚变与等离子体物理 2007年第1期27卷 44-47页

作者： li Xiu-juan RAO Jun wang Ming-wei wang xue-yun li Bo Southwestern Institute of Physics Chengdu 610225

1 Introduction A series of engineering tests and physical experiments,including ECRH[1],was carried out on the HL-2A tokamak in 2005.A fast arcing protection system[2] was developed to ensure operating of ECRH facilit... 详细信息

关键词：弧阈值响应时间托卡马克装置

Wave Attenuation Performance and the Influencing Factors of A Lower Arc-Plate Breakwater

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China Ocean Engineering 2020年第1期34卷 89-98页

作者： li xue-yan wang Qing YOU Zai-jin GUO Wei-jun ZHANG Jun-bin ZHAN Chao ZHANG Zhi-chen wang li-xue li Qin Coast Institute Ludong UniversityYantai 264025China Dalian Maritime University Dalian 116026China Institute of Sea-Crossing Engineering Ludong UniversityYantai 264024China College of Environmental Sciences and Engineering Dalian Maritime UniversityDalian 116026China

Comprehensive experimental and numerical studies have been undertaken to investigate wave energy dissipation performance and main influencing factors of a lower arc-plate breakwater. The numerical model, which considers nonlinear interactions between waves and the arc-plate breakwater, has been constructed by using the velocity wave- generating method, the volume of fluid (VOF) method and the finite volume method. The results show that the relative width, relative height and relative submergence of the breakwater are three main influencing factors and have significant influence on wave energy dissipation of the lower arc-plate open breakwater. The transmission coefficient is found to decrease with the increasing relative width, and the minimum transmission coefficient is 0.15 when the relative width is 0.45. The reflection coefficient is found to vary slightly with the relative width, and the maximum reflection coefficient is 0.53 when the relative width is 0.45. The transmission and reflection coefficients are shown to increase with the relative wave height for approximately 85% of the experimental tests when the relative width is 0.19 0.45. The transmission coefficients at relative submergences of 0.04, 0.02 and 0 are clearly shown to be greater than those at relative submergences of 0.02 and 0.04, while the reflection coefficient exhibits the opposite relationship. After the wave interacts with the lower arc-plate breakwater, the wave energy is mainly converted into transmission, reflection and dissipation energies. The wave attenuation performance is clearly weakened for waves with greater heights and longer periods.

关键词： arc-plate breakwater wave attenuation performance influencing factors VOF method

Sustained release of Semaphorin 3A from a-tricalcium phosphate based cement composite contributes to osteoblastic differentiation of MC3T3-E1 cells

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Frontiers of Materials Science 2015年第3期9卷 282-292页

作者： Jin-Ning wang Bin PI Peng wang xue-Feng li Hui-lin YANG xue-Song ZHU Department of Orthopaedic Surgery The first Affiliated Hospital of Soochow University Suzhou 215006 China

The reinforcement of calcium phosphate materials with silk fibroin （SF） has been one of the strategies to overcome the brittleness. However, the lack of osteoinductivity may still restrict their further use. This study aimed to investigate the biocompatibility and osteogenesis capacity of a novel Semaphorin 3A-loaded chitosan microspheres/SF/a-tricalcium phosphate composite （Sema3A CMs/SF/a-TCP） in vitro. Sema3A was first incorporated into CMs, and the Sema3A CMs/SF/a-TCP composite was then prepared. The morphology of the CMs was observed using SEM. The in vitro release kinetics, cytotoxicity, and cell compatibility were evaluated, and the real-time quantitative polymerase chain reaction （RT-qPCR） and activity of alkaline phosphatase （ALP） were used to evaluate the osteogenesis capacity of the composite. The in vitro release of Sema3A from the Sema3A CMs/SF/a-TCP composite showed a temporally controlled manner. The extract of the Sema3A CMs/SF/a-TCP composite presented no obvious side effect on the MC3T3-E1 cell proliferation, nor promote cell proliferation. The MC3T3-E1 cells were well-spread and presented an elongated shape on the Sema3A CMs/SF/a-TCP composite surface; the ALP activity and the osteogenic-related gene expression were higher than those seeded on the surface of the CMs/SF/a-TCP and SF/a-TCP composites. In conclusion, Sema3A CMslSF/a-TCP has excellent biocompatibility and contributes to the osteoblastic differentiation of MC3T3-E1 cells.

关键词： α-tricalcium phosphate (o-TCP) silk fibroin (SF) Semaphorin 3A osteo-blastic differentiation MC3T3-EI cell

Effects of R-Parity Violating Supersymmetry in Top Pair Production at linear Colliders with Polarized Beams

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Communications in Theoretical Physics 2007年第5X期48卷 891-894页

作者： wang xue-Lei li Ji-Tao liU Su-Zhen College of Physics and Information Engineering Henan Normal University Xinxiang 453007 China

In the minimal supersymmetric standard model with R-parity violation, the lepton number violating top quark interactions can contribute to the top pair production at a linear collider via tree-level u-channel squark exchange diagrams. We calculate such contributions and find that in the allowed range of these R-violating couplings, the top pair production rate as well as the top quark polarization and the forward-backward asymmetry can be significantly altered. By comparing the unpolarized beams with the polarized beams, we find that the polarized beams are more powerful in probing such new physics.

关键词： linear colliders minimal supersymmetric model top quark R-parity

EFFECTS OF RAPAMYCIN ON INTRACELLULAR CHOLESTEROL HOMEOSTASIS OF GLOMERULAR MESANGIAL CELL IN THE PRESENCE OF INTERLEUKIN-1β

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Chinese Medical Sciences Journal 2008年第4期23卷 205-211页

作者： Guo-iuan Zhang Hang li xue-wang li Department of Nephrology Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730

Objective To investigate the effects of rapamycin on cholesterol homeostasis of glomerular mesangial cells and the underlying mechanisms. Methods Intracellular cholesterol accumulation was measured by Oil Red O staining and high performance liquid chromatography. The effects of rapamycin on interleukin-1β（1L-1β）-induced mRNA and protein changes of low-density lipoprotein receptor （LDLR） and ATP-binding cassette transporter Al （ABCAl） were assayed by quantitative real-time PCR and Western blot. Transient expressions of 3 types of mammalian target of rapamycin （mTOR）, including mTOR-WT （wild type）, mTOR-RR （rapamycin resistant, with kinase activity）, and mTOR-RR-KD （rapamycin resistant, without kinase activity）, were obtained by plasmid transfection. Results Rapamycin had no significant influence on intracellular cholesterol concentration trader normal condition, but it significantly decreased the intracellular cholesterol concentration in the presence of IL-1β. Rapamycin dose-dependently suppressed the increased expression of LDLR induced by IL-1β and up-regulated the suppressed expression of ABCAl caused by IL-1β Transient expression of 3 types of mTOR all reduced ABCAl mRNA expression significantly, which all could be overroded by rapamycin. Conclusions Rapamycin may contribute to the maintaining of glomerular mesangial cell intracellular cholesterol homeostasis under inflammatory state by both reducing cholesterol uptake and increasing cholesterol effiux. And the effect may be not completely mediiated by mTOR.

关键词： rapamycin glomerular mesangial cell cholesterol low-density lipoprotein receptor ATP-binding ca, sette transporter A1

Thermoelastic Correction in the Torsion Pendulum Experiment

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Chinese Physics Letters 2001年第1期18卷 7-9页

作者： HU Zhong-Kun wang xue-li LUO Jun Department of Physics Huazhong University of Science and TechnologyWuhan 430074

The thermoelastic effect of the suspension fibre in the torsion pendulum experiment with magnetic damping was *** disagreement in the oscillation periods was reduced by one order of magnitude through monitoring the ambient temperature and thermoelastic *** also found that the period on uncertainty due to noise increases with the amplitude attenuation after thermoelastic correction.

关键词： torsion fibre ambient

lipids-induced Apoptosis Is Aggravated by Acyl-coenzyme A:Cholesterol Acyltransferase Inhibitor

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Chinese Medical Sciences Journal 2010年第2期25卷 76-84页

作者： Jian-ling Tao Xiong-zhong Ruan Hang li xue-mei li xue-wang li Department of Nephrology Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730 China Centre for Nephrology University College London Medical School Royal Free Campus London NW3 2PF UK

Objective To investigate the role of acyl-coenzyme A:cholesterol acyltransferase inhibitor(ACATI) in apoptosis induced by lipids and whether lipids-induced apoptosis is accompanied by increase of free cholesterol in endoplasmic reticulum(ER),in order to further understand the mechanism of lipids-induced apoptosis in advanced *** Human vascular smooth muscle cells(VSMCs) and phorbol 12-myristate 13-acetate(PMA) differentiated THP-1 macrophages were *** thymidine incorporation was applied to detect cell *** was assessed by lactate dehydrogenase(LDH) release.4',6-diamidino-2-phenylindole(DAPI) staining,caspase-3,-7 assay,and Annexin-V/propidium iodide(PI) staining were used to detect *** performance liquid chromatography was used in intracellular free cholesterol and cholesterol ester *** free cholesterol was *** Different lipids had different effects on proliferation and cytotoxicity of VSMCs.25-hydroxycholesterol(25OHC) had biphasic effects on the proliferation of *** low concentration,it stimulated cell proliferation,but turned to proliferation inhibition as concentration reached 15 μg/mL.25OHC and acetylated low density lipoprotein(AcLDL) could respectively induce apoptosis in human VSMCs and PMA differentiated THP-1 macrophages,which was aggravated by ACATI,accompanied by increase of intracellular free cholesterol *** was also an increase of cholesterol content in ER with AcLDL-induced apoptosis in THP-1 *** lipids could induce apoptosis,accompanied by increase of intracellular free cholesterol content,which could be augmented by ACATI,suggesting that insults resulting in ER free cholesterol rise might be the initiator of apoptosis.

关键词： apoptosis atherosclerosis acyl-coenzyme A:cholesterol acyltransferase

Precise Determination of Separation Between Spherical Attracting Masses in Measuring the Gravitational Constant

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Chinese Physics Letters 2001年第8期18卷 1012-1014页

作者： LUO Jun wang Wen-Min HU Zhong-Kun wang xue-li Department of Physics Huazhong University of Science and TechnologyWuhan 430074

A rotating gauge method is used to measure the span between two spheres with high precision in determination of the gravitational constant G.A rectangular gauge block slightly shorter than the span is located horizontally between two spheres,and the angle between two symmetric bounding points during rotation can be determined by measuring the shift of a laser beam passing through an optical plate fixed on the gauge *** results show that the uncertainty in the determination of the span between the two spheres is less than 0.5μm.

关键词： gauge spheres rotating