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Some key technics of drop tower experiment device of National Microgravity Laboratory (China) (NMLC)

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Science China(Technological sciences) 2005年第3期48卷 305-316页

作者： ZHANG Xiaoqian 1 , YUAN Longgen 1 , WU Wendong 1 , TIAN Lanqiao 2.& YAO Kangzhuang 2.1. Institute of Engineering Thermophysics, chinese academy of{2., beijing 100080, China 2. Institute of Mechanics, chinese academy of{2., beijing 100080, China 1. Institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. Institute of Mechanics Chinese Academy of Sciences 100080 Beijing China

Drop tower is an important ground based facility for microgravity science experiment. The technical performances of the drop tower NMLC are advanced compared with similar facilities in the US, Germany and Japan. The main components such as drop capsule, deceleration devices, release mechanism present its advantages and creativities.

关键词： drop tower facility,drop capsule,deceleration devices,release mechanism.

Parentage determination of an isolated Yangtze finless porpoise population Neophocaena phocaenoides asiaeorientalis in the Yangtze Tian-e-Zhou Baiji National Natural Reserve based on molecular data

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Progress in Natural Science:Materials International 2005年第2期15卷 54-61页

作者： XIA Junhong 1,2. ZHENG Jinsong 1,2. XU Limei 1,2.and WANG Ding1*(1. Institute of Hydrobiology, chinese academy of{2., Wuhan 430072. China 2. Graduate School of the chinese academy of{2., beijing 100039, China) Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China. Graduate School of the chinese academy of{2. Beijing 100039 China

Reproductive behaviors are poorly known for the Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis. In this study, the parentage of an isolated Yangtze finless porpoise population inhabiting the Yangtze Tian-e-Zhou Baiji National Natural Reserve is determined by analysis of microsatellite loci and mitochondrial DNA (mtDNA) control region sequences, and the porpoise's reproductive behaviors are studied. Overall 4 full parentage assignments and additional 3 single parentage assignments were determined for the population of 2. individuals. The analysis shows that their estimated reproductive cycle is shorter than that reported previously and there probably exists an overlapping between gestation and lactation period. The study also shows that the female does not show fidelity to a particular male for breeding and vice versa, the oldest males did not monopolize mating and the dominance rank could not be so strict for the porpoise society. Moreover, the porpoise's mating pattern and relatedness among candidate parents are discussed here. These results provide important information for making guidelines of management and conservation for this protected population.

关键词： Yangtze finless porpoise isolated population reproductive behavior parentage

Algebraically explicit analytical solu-tions for the unsteady non-Newtonian swirling flow in an annular pipe

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 396-400页

作者： CAI Ruixian1 & GOU Chenhua1,2.1. Institute of Engineering Thermophysics, chinese academy of{2., beijing 100080, China 2. Graduate School, chinese academy of{2., beijing 100080, China 1. Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China 2. Graduate School Chinese Academy of Sciences Beijing 100080 China

This paper presents two algebraically explicit analytical solutions for the incompressible unsteady rotational flow of Oldroyd-B type in an annular pipe. The first solution is derived with the common method of separation of variables. The second one is deduced with the method of separation of variables with addition developed in recent years. The first analytical solution is of clear physical meaning and both of them are fairly simple and valuable for the newly developing computational fluid dynamics. They can be used as the benchmark solutions to verify the applicability of the existing numerical computational methods and to inspire new differencing schemes, grid generation ways, etc. Moreover, a steady solution for the generalized second grade rheologic fluid flow is also presented. The correctness of these solutions can be easily proven by substituting them into the original governing equation.

关键词： analytical solution, Oldroyd-B type fluid, swirling flow, non-Newtonian.

Discovery of immune related factors in Fenneropenaeus chinensis by annotation of ESTs

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Progress in Natural Science:Materials International 2004年第1期14卷 48-55页

作者： SHEN Yaoqing 1,2. , XIANG Jianhai 1*, WANG Bing 1,2. , LI Fuhua 1 and TONG Wei 3(1. Experimental Marine Biology Laboratory, Institute of Oceanology, chinese academy of{2., Qingdao 2.6071,China 2. Graduate School of the chinese academy of{2., beijing 100039, China 3. Genomics & Bioinformatics Institute, chinese academy of{2., beijing 101300, China) chinese Acad Sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China chinese Acad Sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 10446 expressed sequence tags (ESTs) are obtained by a large scale sequencing of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EST analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these ESTs in order to promptly find possible functional genes, especially for immune related factors. About 4% of the ESTs show similarity to the coding sequences of such factors, including lectin, serine protease, serpin, lysozyme, etc. These ESTs provide a partial profile of the immune system in F. chinensis and useful information for further study on these genes.

关键词： Fenneropenaeus chinensis bioinformatics ESTs immune factors

Ionization state of cosmic hydrogen by early stars and quasars

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Research in Astronomy and Astrophysics 2009年第6期9卷 665-681页

作者： Xiao-Chun Mao1,2.1 National Astronomical Observatories, chinese academy of{2., beijing 100012. China 2.Graduate University of chinese academy of{2., beijing 100049, China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of chinese academy of{2. Beijing 100049 China

Cosmic hydrogen is reionized and maintained in its highly ionized state by the ultraviolet emission attributed to an early generation of stars and quasars. The Lyα opacity observed in absorption spectra of high-redshift quasars permits more stringent constraints on the ionization state of cosmic hydrogen. Based on density perturbation and structure formation theory, we develop an analytic model to trace the evolution of the ionization state in the post-overlap epoch of reionization, in which the bias factor is taken into account. For quasars, we represent an improved luminosity function by utilizing a hybrid approach for the halo formation rate that is in reasonable agreement with the published measurements at 2.≤ z ≤ 6. Comparison with the classic Press-Schechter mass function of dark matter halos, we demonstrate that the biased mass distribution indeed enhances star formation efficiency in the overdense environment by more than 2. per cent following the overlap of ionized bubbles. In addition, an alternative way is introduced to derive robust estimates of the mean free path for ionizing photons. In our model, star-forming galaxies are likely to dominate the ionizing background radiation beyond z = 3, and quasars contribute equally above a redshift of z ～ 2.5. From 5 ≤ z ≤ 6, the lack of evolution in photoionization rate can thus be explained by the relatively flat evolution in star formation efficiency, although the mean free path of ionizing photons increases rapidly. Moreover, in the redshift interval z ～ 2.- 6, the expected mean free path and Gunn-Peterson optical depth obviously evolve by a factor of ～ 500 and ～50 respectively. We find that the relative values of critical overdensities for hydrogen ionization and collapse could be 430% at z ≈2.and 2. at z ≈6, suggesting a rapid overlap process in the overdense regions around instant quasars following reionization. We further illustrate that the absolute estimates of the fraction of neutral hydrogen computed fr

关键词： cosmology theory -- formation galaxies -- quasars general -- diffuse radiation -- intergalactic medium

High Throughput SNP Genotyping with Two Mini-sequencing Assays

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Acta Biochimica et Biophysica Sinica 2004年第6期36卷 379-384页

作者： Chunqing LUO1,2., Libin DENG1#, and Changqing ZENG1,2. The Institute of Genetic and Developmental Biology, the chinese academy of{2., beijing 100101, China 2.3} Genomics Institute, the chinese academy of{2., beijing 101300, China The Institute of Genetic and Developmental Biology the Chinese Academy of SciencesBeijing 100101 China beijing Genomics Institute the Chinese Academy of SciencesBeijing 101300 China

Two mini-sequencing methods, FP-TDI (template-directed dye-terminator incorporation with fluorescence-polarization) and MassArray (matrix assisted laser desorption ionization time of flight detection mass spectrometry), were optimized. A numeric standard was introduced to evaluate the SNP scoring quality of FP-TDI assay, thus made the optimization work easier. At the same time, using multi-PCR technology, 8-plex genotyping of MassArray assay was successfully carried out, some softwares were developed and the data process of MassArray was highly automated. Then these two methods were applied to high throughput SNP genotyping, the accuracy, efficiency and robustness were compared. The result shows FP-TDI is more sensitive to the concentration of SNPprimer and PCR product, as well as extension cycles, the SNPprimer length of FP-TDI should be 2.–30 bp long, whereas MassArray assay prefers to be as short as only 16 *** 6440 SNP sites of human chromosome 3 were genotyped in a sample of 90 individuals, 4792.sites by FP-TDI assay and 1648 sites by MassArray assay, the success rates of FP-TDI and MassArray were 67.7% and 93.6% respectively. The throughput of MassArray was higher than FP-TDI, and the cost of MassArray was lower, MassArray was more suitable for high throughput SNP genotyping.

关键词： SNP genotyping FP-TDI MassArray high throughput

Kinematics and dynamics of the Mesozoic orogeny and late-orogenic extensional collapse in the Sino-Mongolian border areas

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Science China Earth sciences 2005年第7期48卷 849-862页

作者： ZHENG Yadong 1 & WANG Tao2.1. Key Laboratory of Orogenic Belts and Crustal Evolution (Peking University), Ministry of Education, beijing 100871, China 2. Institute of Geology, chinese{2. of Geological sciences, beijing 100037, China Key Laboratory of Orogenic Belts and Crustal Evolution (Peking University) Ministry of Education Beijing 100871 China Institute of Geology Chinese Academy of Geological Sciences Beijinq 100037 China

The Sino-Mongolian border areas underwent two important tectonic events during Mesozoic time after late Paleozoic orogeny: a late Triassic to earlier Jurassic contractional event that resulted in a large-scale south-vergent thrust during the orogeny and a late Jurassic-earlier Cretaceous extensional event in a north-south direction that formed a metamorphic core complex. The kinematic and dynamic analyses show that the thrust sheet moved southwards with a kinematic vorticity number of ca. -0.10 and sub-horizontal maximum compressive stress axis that belongs to a contraction-thickening shear. The upper plate of the late-orogenic detachment relatively moved in a 165°direction. The average kinematic vorticity in its earlier stage was 0.74 that belongs to simple shear dominated shearing and related to the maximum compressive stress axes dipping at ～66°, while the later average kinematic vorticity was ～0.55°that belongs to pure shear dominated shearing with sub-vertical maximum compressive stress axes. This suggests that the thrusting led to the crust thickened and the lower plate rocks that were originally located in the upper crust depressed through a brittle-ductile transition zone into the lower crust and became warmer. The heated rocks trended to uplift since their increasing volume and decreasing density while the loading of the upper-plate rocks increased due to the structural thickening. Under the combined effect of the loading and the thermal-uplifting, the ductile shear zone in between increased in its component of vertical pure shear. Once its pure-shear component exceeded its simple-shear one the ductile shear zone became an extension-thinned shear zone. This progressive transitional process reflects internal and essential temporal and spatial relationships: the extensional factor nucleated during the crust thickening by thrusting and increase of the extensional factor finally led to late-orogenic collapse.

关键词： Mesozoic thrusting,late-orogenic collapse,kinematic vorticity number,stress state.

GM-CSF-induced Ca_(2.) -activated non-voltage-dependent inwardly rectifying K_+ channel in murine peritoneal exudate macrophages

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chinese Science Bulletin 1997年第11期42卷 947-952页

作者： ZHANG Xiaofeng, FENG Meifu, WU Caihong and ZHOU Pei’aiState Key Laboratory of Biomembrane and Membrane Biotechnology, chinese academy of{2., beijing 100080, China 1 . In-stitute of Zoology, chinese academy of{2., beijing 100080, China 2.College of Life{2., Peking University, beijing 100871, China State Key Laboratory of Biomembrane and Membrane Biotechnology Chinese Academy of Sciences Beijing 100080 China

GRANULOCYTE-MACROPHAGE colony-stimulating factor(GM-CSF),a member in the family ofglycoprotein cytokines,can not only act to stimulate proliferation of immature progenitors,butalso enhance differentiated functions of mature effector *** has two kinds of biologicaleffects on mature effector cells,*** effect and indirect *** latter is also

关键词： K+ channel patch clamp GM-CSF macrophage.

On the local wellposedness of 3-D water wave problem with vorticity

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Science China Mathematics 2007年第8期50卷 1065-1077页

作者： Ping ZHANG~1 Zhi-fei ZHANG~2.1 academy of Mathematics and Systems Science,chinese academy of sciences,beijing 100080,China 2.School of Mathematical sciences,Peking University,beijing 100871,China academy of Mathematics Systems Science Chinese Academy of Sciences Beijing 100080 China School of Mathematical sciences Peking University Beijing 100871 China

In this article, we first present an equivalent formulation of the free boundary problem to 3-D incompressible Euler equations, then we announce our local wellposedness result concerning the free boundary problem in Sobolev space provided that there is no self-intersection point on the initial surface and under the stability assumption that $\frac{{\partial p}}{{\partial n}}(\xi )\left| {_{t = 0} } \right. \leqslant - 2._0 < 0$ being restricted to the initial surface.

关键词： water-waves free boundary incompressible Euler equations primary 35Q35 76B03 secondary 35J67 35L80