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Permian carbonates of Baoshan block, Western Yunnan and their paleoclimatic implications

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Science china Earth sciences 2004年第5期47卷 385-392页

作者： YAN Jiaxin1, LIANG Dingyi1 & WU Ming2 1. Faculty of Earth sciences, china university of Geosciences, wuhan 430074, china 2. college of Chemistry and life sciences, South-Central university for Nationalities, wuhan 430074, china china Univ Geosci Fac Earth Sci Wuhan 430074 Peoples R China S Cent Univ National Coll Chem & Life Sci Wuhan 430074 Peoples R China

Recently, much attention has been paid to the climatic significance of carbonates originating in shallow water. Permian carbonates of shallow shelf origin are present in the upper part of the Dingjiazhai Formation, the upper part of the Yongde Formation, and the Shazipo Formation on the Baoshan block of Western Yunnan. Their skeleton and non-skeleton grain as-sociations have been investigated in this study. The carbonates of the Dingjiazhai Formation indicate a Bryonoderm (bryozoans-echinoderm) association without non-skeleton grains. The carbonates of Yongde and Shazipo formations show Chloroforam (green algae-foraminifers) association with peloids. Oolites develop in the Shazipo Formation. Based on the comparisons of grain association with coeval carbonates formed in different paleolatitudes (i.e. various paleo-climatic zones), the carbonates of the Dingjiazhai Formation were thought to have been accu-mulated in shelf environments of warm-temperate zone, and those of the Yongde and Shazipo formations in shelf environments of warm-water.

关键词： Early Permian, carbonate, paleoclimate, Western Yunnan.

DOUBLE Φ-FUNCTION INEQUALITY FOR NONNEGATIVE SUBMARTINGALES

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 211-216页

作者： MEI TAO(college of Mathematics and Computer sciences, wuhan university, wuhan 430072, china.) LIU PEIDE(college of Mathematics and Computer sciences, wuhan university, wuhan 430072, china.) college of Mathematics and Computer sciences Wuhan University Wuhan 430072 China

The authors establish a kind of inequalities for nonnegative submartingales which depend on two functions　ψ and ψ, and obtain the equivalent conditions for　Φ and ψ such that this kind of inequalities holds. In t... 详细信息

关键词： Matingale Nonnegative submartingale Maximal function Φ-function inequality

Milestone of the meridian science──970th anniversary of the Chinese Bronze Statue of Meridian

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Chinese Science Bulletin 1998年第5期43卷 353-362页

作者： ZHANG Renji college of life sciences, Peking university, Beijing 100871, china college of life sciences Peking University Beijing 100871 China

For more than a thousand years, Chinese people were aware of the transmitted sensations by the application of needles on the body surface. This practice is called acupuncture. Acupuncture had been recorded and transcribed in writings and in drawings, until finally the acupoints were inscribed onto a bronze statue. The bronze statue was called the Meridian Figure. Deeply embodied in the bronze statue is a tripartite confrontation-prism representation of the humans body. This concept was a great scientific achievement in ancient china. The author traces the history of Meridian science described in traditional Chinese medical terms. Then he explores a clear analogy of the meridian pathway (MP) phenomenon. In a model system, by using a simple segmental in vertebrate, certain parallels can be demonstrated with the meridian concept. For example, the author demonstrated a clear correlation rule among the central mechano-sensory channels, and characteristics of positional discrimination in individual nerve cells from different receptive field inputs. The evidence suggests that the MP phenomenon is an objective neurobiological response. To clarify the research objective in this paper, the author suggests that the MP is a bi-directional pathway along which a positional message signal is transmitted. This phenomenon is evoked by physical stimulation, transmitted linearly across the human body segments, and is perceived by the brain. The MP consists of low resistance paths, is connected by the liquid media contained in the apposite membranous structure. At the cellular level, the regulation functions of MP must pass through along this low resistance path. Two aspects of the modern Meridian research are the functional regulation and the mechanism of intercellular liquid modulation at the nanometer level.

关键词： meridian pathway tripartite confrontation-prism coordinate position discriminative recognition apposite membranous structure.

Synthesis and Characterization of Two New Photochromic Inorganic-organic Hybrid Materials Based on Keggin-type Polyoxometalates

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Journal of wuhan university of Technology(Materials Science) 2008年第3期23卷 367-371页

作者：库宗军 college of Chemistry and Materials sciences Xiaogan University

Two new photochromic inorganic-organic hybrid materials formed from Keggin-type polyoxometalates（POMs） and metronidazole （C6H9N3O3, MNZ）, formulated as H3PMo12OaO-3MNZ·3H2O （1） and H3PW12O40.3MNZ·3H2O（2）, were synthesized and characterized by elemental analysis, IR spectra, electronic spectra, electron spin resonance （ESR） spectra and thermogravi-metry-differential thermal analysis （TG-DTA）. Reflectance spectra show the presence of weak intermolecular charge transfer between the organic and inorganic moieties in the solid state. The photochromic properties were studied by solid diffuse reflectance spectra and ESR spectra, and the photochromic reactions were found to exhibit first-order kinetics. TG-DTA showed that two hybrid materials have similar thermal behavior.

关键词： polyoxometalate metronidazole hybrid material photochromism kinetics

Nitrogen-Fixing Inhibition by KCl in A Blue-Green Alga Anabaena cylindrica

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wuhan university Journal of Natural sciences 1998年第2期3卷 239-242页

作者： Yi Ping,Guo Houliang, Huang Kaiyao(college of life sciences, wuhan university, wuhan 430072,china) college of life sciences Wuhan University Wuhan 430072 China

Growing in the medium containing 0.10 mol/L KCl for three days, the nitrogen-fixing activity ofAnabaena cylindrica decreased by 95%. Extent of the inhibition was enchanced with increased KCl concentrations. The biggest decrease of nitrogen-fixing activity was between 0.02–0.05 mol/L KCl. The same decline on growth was between 0.05–0.10 mol/L KCl. The longer treating-time was, the lower nitrogen-fixing activity was. A short time of KCl-treatment (for 4 h) resulted in 66.4%decrease of the activity. Under effecting of KCl for three days, the frequency of heterocyst differentiation decreased from 7.2%to 2.1%.

关键词： Anabaena cylindrica salt stress nitrogen fixing activity

life History Traits and Mechanisms of Endangerment in Ranalisma rostratum

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wuhan university Journal of Natural sciences 1998年第2期3卷 231-234页

作者： Wang Jianbo,Chen Jiakuan, Li Rongqian(college of life sciences,wuhan university,wuhan 430072, china) wuhan university College of Life Sciences Wuhan China (GRID:grid.49470.3e) (ISNI:***)

Ranalisma rostratum (Alismataceae) is an endangered aquatic plant, and now there is only one population existing in china. In its natural habitat, Huli marsh in Chaling, Hunan province, the best growing plants have been observed at microsites where the water depth is 5～10cm, and the plants grow in emergent form.R. rostratum reproduces asexually or sexually. The recruitment of asexual propagules into population is a very important way to maintain the natural population size. Although seed production does not appear to limitR. rostratum, restricted dispersal of propagules and seeds, low seed viability, low germinability, slow growth of seedlings under all conditions, and habitat loss due to agriculture appear to be more important reasons for the endangerment of this plant.

关键词： Key words Ranalism rostratum life history mechanism of endangerment

Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1 Ya-Xuan SUN~2 Zhao-Feng JIANG~2* 1 college of life Science,Capital Normal university,Beijing 100037,china 2.college of Applied sciences and Humanities,Beijing Union university,Beijing 100083,china college of life Science Capital Normal UniversityBeijing 100037 China college of Applied sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2+and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure

Peplomycin induces G1-phase specific apoptosis in liver carcinoma cell line Bel-7402 involving G2-phase arrest

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Acta Pharmacologica Sinica 2004年第12期25卷 132-138页

作者： Hong-ying CHEN2, Cong-yi ZHENG2, Guo-lin ZOU2, Da-xing XIE3, Jian-ping GONG3 2college of life sciences, wuhan university, wuhan 430072 3Cancer Research Institute, Tongji Hospital, TongjiMedical college, Huazhong university of Science and Technology, wuhan 430072, china college of life sciences Wuhan University Wuhan 430072 China

AIM: To investigate the mechanism of peplomycin (PEP)-induced apoptosis in liver carcinoma cell line (Bel-7402). METHODS: Growth inhibition by PEP was analyzed using 3- 4,5-Dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptotic cells were detected using Hoechest 33258 staining, and confirmed by flow cytometric analysis and DNA fragmentation analysis. The expression of cyclin A and B1 were determined by flow cytometry and Western blot. Annexin V assay was measured by flow cytometric analysis. RESULTS: PEP induced apoptosis and then inhibited cell proliferation in liver carcinoma cell line Bel-7402. Cells treated with PEP 50 μmol/Lfor 15 h were arrested in G2-phase with dramatical expression of cyclin A and a little change in cyclin B1. Almost all the apoptosis occurred in cells undergoing the G1-phase after treatment for 24 h. CONCLUSION: Peplomycin induced G1-phase specific apoptosis in Bel-7402 involving G2-phase arrest.

关键词： peplomycin Bel-7402 cells apoptosis cyclins cell cycle flow cytometry

The structure and function of catalytic RNAs

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Science china(life sciences) 2009年第3期52卷 232-244页

作者： WU QiJia,HUANG Lin & ZHANG Yi State Key Laboratory of Virology,college of life sciences,wuhan university,wuhan 430072,china 1. State Key Laboratory of Virology College of Life Sciences Wuhan University Wuhan 430072 China

Before the discovery of ribozymes,RNA had been proposed to function as a catalyst,based on the discovery that RNA folded into high-ordered structures as protein *** hypothesis was confirmed in the 1980s,after the discovery of Tetrahymena group I intron and RNase P *** have been about ten ribozymes identified during the past thirty years,as well as the fact that ribosomes function as *** have been made in understanding the structures and functions of ribozymes,with numerous crystal structures resolved in the past *** we review the structure-function relationship of both small and large ribozymes,especially the structural basis of their catalysis.

关键词： ribozyme structure catalysis