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Role of plasminogen activators and inhibitors in reproduction

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chinese Science Bulletin 1999年第8期44卷 673-685页

作者： LIU YixunState key laboratory of Reproductive Biology, Institute of Zoology , chinese academy of sciences , beijing 100080, china State key laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing China

The recent progress in the studies on the role of local and directed fibrinolysis controlled by plasminogen activators (PAs) and regulated by their inhibitors (PAIs) in reproduction is summarized. Hormone-induced coordinated expression of tissue type PA (tPA) and PAI type-1 (PAI-1) in the ovary is involved in the processes of ovulation and luteal regression; increases in urokinase type PA (uPA) and PAI-1 activity in the early stage of luteinized follicles may be responsible for ovarian tissue remodeling and angiogenesis; the PA system has been found to play an important role in spermatogenesis in testis and modulation of sperm maturation in epididymis. PA and matrix matalloproteanase (MMP) and their respective inhibitors have also been identified in trophoblast and uterus. The targeted proteolytic activity generated by the two systems may play an essential role in the processes of the cyclic uterine angiogenesis, implantation and pla-centation as well as parturition.

关键词： plasminogen activator and inhibitor follicle rupture luteolysis angiogenesis spermatogenesis placentation.

Focal plane wave-front sensing algorithm for high-contrast imaging

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Science china(Physics,Mechanics & Astronomy) 2009年第8期52卷 1284-1288页

作者： DOU JiangPei1,2,3,REN DeQing1,2,4,ZHU YongTian1,2 & ZHANG Xi1,2,3 1 national astronomical observatories/Nanjing Institute of astronomical Optics & Technology,chinese academy of sciences,Nanjing 210042,china 2 key laboratory of astronomical Optics & Technology,Nanjing Institute of astronomical Optics & Technology,chinese academy of sciences,Nanjing 210042,china 3 Graduate University of chinese academy of sciences,beijing 100049,china 4 Physics & Astronomy Department,California State University Northridge,18111 Nordhoff Street,Northridge,California 91330-8268,USA national astronomical observatories/Nanjing Institute of astronomical Optics & Technology Chinese Academy of Sciences Nanjing China key laboratory of astronomical Optics & Technology Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing China Graduate University of chinese academy of sciences Beijing China Physics & Astronomy Department California State University Northridge Northridge USA

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star.A major limitation for such direct imaging is the speckle noise that is induced from the wave-front error of an optical *** derive an algorithm for the wave-front measurement directly from 3 focal plane *** 3 images are achieved through a deformable mirror to provide specific phases for the optics *** introduce an extra amplitude modulation on one deformable mirror configuration to create an uncorrelated wave-front,which is a critical procedure for wave-front *** simulation shows that the reconstructed wave-front is consistent with the original wave-front theoretically,which indicates that such an algorithm is a promising technique for the wave-front measurement for the high-contrast imaging.

关键词： high-contrast imaging multi-image algorithm speckle nulling technique wave-front sensing

Temporal variation of hemispheric solar rotation

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Research in Astronomy and Astrophysics 2012年第2期12卷 187-200页

作者： Jing-Lan Xie 1,2,Xiang-Jun Shi 1,2 and Jing-Chen Xu 1,21 national astronomical observatories /Yunnan Observatory,chinese academy of sciences,Kunming 650011,china 2 Graduate University of chinese academy of sciences,beijing 100049,china national astronomical observatories/Yunnan Observatory Chinese Academy of Sciences Graduate University of chinese academy of sciences

The daily sunspot numbers of the whole disk as well as the northern and southern hemispheres from 1945 January 1 to 2010 December 31 are used to investi- gate the temporal variation of rotational cycle length through the continuous wavelet transformation analysis method. Auto-correlation function analysis of daily hemi- spheric sunspot numbers shows that the southern hemisphere rotates faster than the northern hemisphere. The results obtained from the wavelet transformation analysis are that no direct relationship exists between the variation trend of the rotational cy- cle length and the solar activity in the two hemispheres and that the rotational cycle length of both hemispheres has no significant period appearing at 11 yr, but has a sig- nificant period of about 7.6 yr. Analysis concerning the solar cycle dependence of the rotational cycle length shows that acceleration seems to appear before the minimum time of solar activity in the whole disk and the northern hemisphere, respectively. Furthermore, the cross-correlation study indicates that the rotational cycle length of the two hemispheres has different phases, and that the rotational cycle length of the whole disk as well as the northern and southern hemispheres, also has phase shifts with corresponding solar activity. In addition, the temporal variation of the north-south （N- S） asymmetry of the rotational cycle length is also studied. This displays the same variation trend as the N-S asymmetry of solar activity in a solar cycle, as well as in the considered time interval, and has two significant periods of 7.7 and 17.5 yr. Moreover, the rotational cycle length and the N-S asymmetry of solar activity are highly corre- lated. It is inferred that the northern hemisphere should rotate faster at the beginning of solar cycle 24.

关键词： Sun: activity - Sun: rotation - Sun: sunspot

Regulation mechanism of EM parameters in natural ferrite and its application in microwave absorbing materials

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Science china(Technological sciences) 2006年第1期49卷 38-49页

作者： ZHENG Yongchun1,2, WANG Shijie2, FENG Junming2, LI Chunlai1, OUYANG Ziyuan1,2, LIU Jianzhong1 & LI Xiaobiao2 1. national astronomical observatories, chinese academy of sciences, beijing 100012, china 2. State key laboratory of Environmental Geochemistry, Institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china national astronomical observatories Chinese Academy of Sciences Beijing 100012 China

Electromagnetic (EM) parameters (ε ′, ε ″, μ ′, μ″ ) of several M2+Fe2O4 and Fe2O3 type natural ferrites with different geological occurrences are measured in this pa-per. The measurement results show that EM parameters of a magmatic-occurring natural ferrite is very different from other types occurring from sedimentary-metamorphic iron deposit, hydrothermal vein iron deposit, outer contact of magmatic iron deposit. It has potential to be used as magnetic absorbent in microwave absorbing materials. After min-eral separation and concentration, this magmatic-occurring natural ferrite was processed into type A ferrite absorbent. Type A natural ferrite absorbent is a kind of magnetic material with low dielectric constants, high magnetic conductivity and high EM loss. Its EM pa-rameters are ε ′ = 58.60, ε ″ = 10.0, μ ′ = 1.2-1.5, μ ″ = 1.0-1.2, respectively. In order to illuminate the regulation mechanism of EM parameters, we studied the chemical and mineral composition of type A ferrite absorbent. There is high concentration of natural impurities, which regulate the EM parameters of type A ferrite greatly. For comparison, the other types of natural ferrite, single-phase magnetite and two-phase iron minerals (ilmen-ite and magnetite), have few impurity. Thus regulation mechanism of EM parameters was absent in these ferrites. As a result, the regulation of EM parameters is advantageous to develop type A natural ferrite as excellent absorbent, lowers the reflectivity coefficients and enhances the absorbing efficiency of MAM made from it. Furthermore, the impurities in type A natural ferrite and its effects on EM parameters are very difficult to simulate in the synthesize ferrite. The carbonyl-iron powder is another kind of absorbent that is used ex-tensively in MAM. To compare the absorbing properties of these two absorbent, type A natural ferrite and carbonyl-iron powder were mixed with rubber and processed into mi-crowave absorbing sheets with the same procedures and tec

关键词： natural impure ferrite, complex permittivity, complex permeability, microwave absorbing materials.

Possible triggering of solar activity to big earthquakes (Ms ≥ 8) in faults with near west-east strike in china

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Science china(Physics,Mechanics & Astronomy) 2004年第2期47卷 173-181页

作者： HAN Yanben1, GUO Zengjian1,2, WU Jinbing1,2 & MA Lihua1 1. national astronomical observatories, chinese academy of sciences, beijing 100012, china 2. Earthquake Research Institute of Lanzhou, CSB, Lanzhou 73000, china Correspondence should be addressed to Han Yanben (email: hyb@***) national astronomical observatories Chinese Academy of Sciences Beijing China Earthquake Research Institute of Lanzhou CSB Lanzhou China

This paper studies the relationship between solar activity and big earthquakes (Ms≥8) that occurred in china and western Mongolia. It is discovered that the occurrence dates of most of the big earthquakes in and near faults with west-east strike are close to the maximum years of sunspot numbers, whereas dates of some big earthquakes which are not in such faults are not close to the maximum years. We consider that it is possibly because of the appearance of many magnetic storms in the maximum years of solar activity. The magnetic storms result in anomalies of geomagnetic field and then produce eddy current in the faults gestating earthquake with near west-east strike. Perhaps the gestated big earthquakes occur easily since the eddy current heats the rocks in the faults and therefore decreases the shear resistant intensity and the static friction limit of the rocks .

关键词： earthquake, solar activity, magnetic storm, eddy current.

The Prediction of Maximum Amplitudes of solar Cycles and the Maximum Amplitude of solar Cycle 24

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chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 557-562页

作者： Jia-Long Wang, Jian-Cun Gong, Si-Qing Liu, Gui-Ming Le and Jing-Lan Sun1 national astronomical observatories, chinese academy of sciences, beijing 1000122 Center for Space Science and Applied Research, chinese academy of sciences, beijing 100080 national astronomical observatories CAS NAOC Beijing 100012 China Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080

We present a brief review of predictions of solar cycle maximum amplitude with a lead time of 2 years or more. It is pointed out that a precise prediction of the maximum amplitude with such a lead-time is still an open question despite progress made since the 1960s. A method of prediction using statistical characteristics of solar cycles is developed: the solar,cycles are divided into two groups, a high rising velocity (HRV) group and a low rising velocity (LRV) group, depending on the rising velocity in the ascending phase for a given duration of the ascending phase. The amplitude of solar Cycle 24 can be predicted after the start of the cycle using the formula derived in this paper. Now, about 5 years before the start of the cycle, we can make a preliminary prediction of 83.2-119.4 for its maximum amplitude.

关键词： Sun : sunspots Sun : activity

Further study on Ca_(2+) -mediated inhibition of human erythrocyte D-glucose transporter

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chinese Science Bulletin 1997年第10期42卷 871-875页

作者： XIE Wensheng, TU Yaping and YANG FuyuState key laboratory of Biomacromolecules, Institute of Biophysics, chinese academy of sciences, beijing 100101, china State key laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing China

THE transport of D-glucose to erythrocytes is catalyzed by an integral membrane protein,*** D-glucose *** specifically carries D-glucose,driven by glucose’s *** of its relative abundance and higher transport activity... 详细信息

关键词： Ca2+ glucose transporter transporting activity inhibition.

Spectral analysis of two solar twins and the colors of the Sun

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Science china(Physics,Mechanics & Astronomy) 2010年第8期53卷 579-585页

作者： ZHAO ZhengShi1,2, CHEN YuQin1, ZHAO JingKun1 & ZHAO Gang1 1 national astronomical observatories, chinese academy of sciences, beijing 100012, china 2 Graduate University of chinese academy of sciences, beijing 100049, china national astronomical observatories Chinese Academy of Sciences Graduate University of chinese academy of sciences

High resolution (R^40,000) and high signal-to-noise ratio (>150) spectra of two solar twins, HD146233 and HD195034, are obtained with the Coude Echelle Spectrograph at the 2.16 m telescope of the national astronomical observatories of chinese academy of sciences (Xinglong, china). Based on the detailed spectrum match, comparisons of chemical composition and chromospheric activity, HD146233 and HD195034 are confirmed that they are similar to the Sun except for lithium abundance, which is higher than the solar value. Moreover, among nine solar twin candidates (including HD146233 and HD195034) found in the previous works, we have picked out six good solar twin candidates based on newly-derived homogenous parameters, and collected their colors in the Johnson/Cousins, Tycho, 2MASS and Strmgren system from the literature. The average color are (B-V)⊙=0.644 mag, (V-Ic)⊙=0.707 mag, (BT-VT)⊙=0.725 mag, (J-H)⊙=0.288 mag, (H-K)⊙=0.066 mag, (v-y)⊙=1.028 mag, (v-b)⊙=0.619 mag, (u-v)⊙=0.954 mag and (b-y)⊙=0.409 mag, which represent the solar colors with higher precision than previous works.

关键词： Sun-colors Star-atmospheres abundances fundamental parameters

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A Running Average Method for Predicting the Size and Length of a solar Cycle

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chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 477-488页

作者： Zhan-Le Du Hua-Ning Wang Li-Yun Zhang national astronomical observatories Chinese Academy of Sciences Beijing 100012 China

The running correlation coefficient between the solar cycle amplitudes and the max-max cycle lengths at a given cycle lag is found to vary roughly in a cyclical wave with the cycle number, based on the smoothed monthly mean Group sunspot numbers available since 1610. A running average method is proposed to predict the size and length of a solar cycle by the use of the varying trend of the coefficients. It is found that, when a condition （that the correlation becomes stronger） is satisfied, the mean prediction error （16.1） is much smaller than when the condition is not satisfied （38.7）. This result can be explained by the fact that the prediction must fall on the regression line and increase the strength of the correlation. The method itself can also indicate whether the prediction is reasonable or not. To obtain a reasonable prediction, it is more important to search for a running correlation coefficient whose varying trend satisfies the proposed condition, and the result does not depend so much on the size of the correlation coefficient. As an application, the peak sunspot number of cycle 24 is estimated as 140.4 ± 15.7, and the peak as May 2012 ±11 months.

关键词： Sun activity -- Sun sunspots - Sun general