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Carbon Monoxide-induced Stomatal Closure Involves Generation of Hydrogen Peroxide in Vicia faba Guard Cells

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Journal of Integrative Plant Biology 2008年第12期50卷 1539-1548页

作者： xiao-Ping She xi-gui Song School of Life Sciences Shaanxi Normal University Xi'an 710062 China

Here the regulatory role of CO during stomatal movement in Vicia faba L. was surveyed. Results indicated that, like hydrogen peroxide （H2O2）, CO donor HemaUn induced stomatal closure in dose- and time-dependent manners. These responses were also proven by the addition of gaseous CO aqueous solution with different concentrations, showing the first time that CO and H2O2 exhibit the similar regulation role in the stomatal movement. Moreover, our data showed that ascorbic acid （ASA, an important reducing substrate for H2O2 removal） and diphenylene iodonium （DPI, an inhibitor of the H2O2-generating enzyme NADPH oxidase） not only reversed stomatal closure by CO, but also suppressed the H2O2 fluorescence induced by CO, implying that CO induced-stomatal closure probably involves H2O2 signal. Additionally, the CO/NO scavenger hemoglobin （Hb） and CO specific synthetic inhibitor ZnPPIX, ASA and DPI reversed the darkness-induced stomatal closure and H2O2 fluorescence. These results show that, perhaps like H2O2, the levels of CO in guard cells of V. faba are higher in the dark than in light, HO-1 and NADPH oxidase are the enzyme systems responsible for generating endogenous CO and H2O2 in darkness respectively, and that CO is involved in darkness-induced H2O2 synthesis in V. faba guard cells.

关键词： carbon monoxide guard cells hydrogen peroxide signaling stomata.

Detection performance and inversion processing of logging-while-drilling extra-deep azimuthal resistivity measurements

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Petroleum Science 2019年第5期16卷 1015-1027页

作者： Lei Wang Shao-gui Deng Pan Zhang ying-Chang Cao Yi-Ren Fan xi-Yong Yuan School of Geosciences China University of PetroleumQingdao 266580ShandongChina Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071ShandongChina CNPC Key Laboratory for Well Logging China University of PetroleumQingdao 266580ShandongChina

We present systematic investigations on the physics,detection performance and inversion of logging-while-drilling extradeep azimuthal resistivity measurements(EDARM).First,the definitions of EDRAM measurements are discussed,followed by the derivation of the attenuation and phase-shift geometrical factors to illustrate the relative contributions of formation units to the observed ***,a new definition of detection depth,which considers the uncertainty of inversion results caused by the data noise,is proposed to quantify the detection capability of ED ***,the B ayesian theory associated with Markov chain Monte Carlo sampling is introduced for fast processing of EDARM *** results show that ED ARM is capable of detecting the azimuth and distance of remote bed boundaries,and the detection capability increases with increasing spacing and resistivity *** EDARM tool can accommodate a large range of formation resistivity and is able to provide the resistivity anisotropy at arbitrary relative dipping *** addition,multiple bed boundaries and reservoir images near the borehole are readily obtained by using the Bayesian inversion.

关键词： Extra-deep azimuthal resistivity measurements(EDARM) Detection performance Inversion method Reservoir imaging Detection of multiple bed boundaries

Graphs Isomorphic to Their Maximum Matching Graphs

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Acta Mathematica Sinica,English Series 2009年第9期25卷 1507-1516页

作者： Yan LIU gui ying YAN School of Mathematics South China Normal University Guangzhou 510631 P.R. China Academy of Mathematics and Systems Science Chinese Academy of Science Beijing 100190 P.R. China

The maximum matching graph M（G） of a graph G is a simple graph whose vertices are the maximum matchings of G and where two maximum matchings are adjacent in M（G） if they differ by exactly one edge. In this paper, ... 详细信息

关键词： isomorphic maximum matching graph bipartite graph factor-critical graph

An epigenetic regulatory switch controlling temperature-dependent sex determination in vertebrates

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Science China(Life Sciences) 2018年第8期61卷 996-998页

作者： xi-Yin Li Jian-Fang gui State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology The Innovative Academy of Seed Design Chinese Academy of Sciences Wuhan 430072 China University of Chinese Academy of sciences Beijing 100049 China

Most vertebrates present two sexes, and females and males are determined via two diverse strategies including geno-typic sex determination （GSD） and environmental sex de-termination （ESD）（Mei and gui, 2015; Ma et al., 2016）. The most common form of ESD is temperature-dependent sex determination （TSD）. Although several master sex-de-termining genes and their molecular pathways have been elucidated in vertebrates with GSD, the molecular mechan-ism underlying TSD remains unclear （Bachtrog et al., 2014; Capel, 2017）.

关键词：脊椎动物温度依赖开关控制性别规章环境性 gui ESD

The Distance Matching Extension in K_(1,k)-free Graphs with High Local Connectedness

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Acta Mathematicae Applicatae Sinica 2022年第1期38卷 37-43页

作者： Wei-chan LIU gui-ying YAN Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

A matching is extendable in a graph G if G has a perfect matching containing it.A distance q matching is a matching such that the distance between any two distinct matching edges is at least *** this paper,we prove that any distance 2k-3 matching is extendable in a connected and locally(k-1)-connected K1,k-free graph of even ***,we also prove that any distance q matching M in an r-connected and locally(k-1)-connected K1,k-free graph of even order is extendable provided that|M|is bounded by a function on r,k and *** results improve some results in[*** Theory 93(2020),5–20].

关键词： distance matching extension perfect matching K1,k-free graph local connectedness

Control design of 60kW PEMFC generation system for residential applications

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第9期14卷 679-685页

作者： ying-ying ZHANG ying ZHANG xi LI Guang-yi CAO Shandong Provincial Key Laboratory of Ocean Environment Monitoring Technology Institute of Oceanographic Instrumentation Shandong Academy of Sciences Control Science and Engineering Department Key Laboratory of the Ministry of Education for Image Processing and Intelligent Control Huazhong University of Science and Technology Fuel Cell Institute Department of Automation Shanghai Jiao Tong University

This paper presented a control design methodology for a proton exchange membrane fuel cell (PEMFC) generation system for residential applications. The dynamic behavior of the generation system is complex in such applications. A comprehensive control design is very important for achieving a steady system operation and efficiency. The control strategy for a 60 kW generation system was proposed and tested based on the system dynamic model. A two-variable single neuron proportional-integral (PI) decoupling controller was developed for anode pressure and humidity by adjusting the hydrogen flow and water injection. A similar controller was developed for cathode pressure and humidity by adjusting the exhaust flow and water injection. The desired oxygen excess ratio was kept by a feedback controller based on the load current. An optimal seeking controller was used to trace the unique optimal power point. Two negative feedback controllers were used to provide AC power and a suitable voltage for residential loads by a power conditioning unit. Control simulation tests showed that 60 kW PEMFC generation system responded well for computer-simulated step changes in the load power demand. This control methodology for a 60 kW PEMFC generation system would be a competitive solution for system level designs such as parameter design, performance analysis, and online optimization.

关键词： Proton exchange membrane fuel cell (PEMFC) Generation system Control strategy decoupling control Optimalseeking control

Microstructure and physical properties of steel-ladle purging plug refractory materials

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International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 186-193页

作者： Bin Long gui-ying Xu Buhr Andreas School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Almatis Qingdao Co. Ltd. Qingdao 266071 China Almatis GmbH Frankfurt 60528 Germany

Three different castables were prepared as steel-ladle purging-plug refractory materials： corundum-based low-cement castable （C-LCC）, corundum-spinel-based low-cement castable （C-S-LCC）, and no-cement corundum-spinel castable （C-S-NCC）（hydratable alu- mina p-A1203 bonded）. The properties of these castables were characterized with regard to water demand/flow ability, cold crushing strength （CCS）, cold modulus of rupture （CMoR）, permanent linear change （PLC）, apparent porosity, and hot modulus of rupture （HMoR）. The re- sults show the CCS/CMoR and HMoR of C-LCC and C-S-LCC are greater than those of the castable C-S-NCC. According to the micro- structure analysis, the sintering effect and the bonding type of the matrix material differ among the three castables. The calcium hexaluminate （CA6） phase in the matrix of C-LCC enhances the cold and hot mechanical strengths. In the case of C-S-LCC, the CA6 and 2CaO·2MgO·14A12O3（C2MEA14） ternary phases generated from the matrix can greatly increase the cold and hot mechanical strengths. In the case of the no-cement castable, sintering becomes difficult, resulting in a lower mechanical strength.

关键词： refractory materials purging plugs castable physical properties microstructure

Effects of fluid recirculation on mass transfer from the arterial surface to flowing blood

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Acta Mechanica Sinica 2012年第3期28卷 904-910页

作者： Zhi-Guo Zhang xi-Wen Zhang ying-xi Liu Department of Engineering Mechanics Faculty of Vehicle Engineering and MechanicsState Key Laboratory of Structural Analysisfor Industrial EquipmentDalian University of Technology116024 DalianChina School of Aerospace Tsinghua University100084 BeijingChina

The effect of disturbed flow on the mass trans- fer from arterial surface to flowing blood was studied nu- merically, and the results were compared with that of our previous work. The arterial wall was assumed to be vis- coelastic and the blood was assumed to be incompressible and non-Newtonian fluid, which is more close to human arte- rial system. Numerical results indicated that the mass trans- fer from the arterial surface to flowing blood in regions of disturbed flow is positively related with the wall shear rates and it is significantly enhanced in regions of disturbed flow with a local minimum around the reattachment point which is higher than the average value of the downstream. There- fore, it may be implied that the accumulation of cholesterol or lipids within atheromatous plaques is not caused by the reduced efflux of cholesterol or lipids, but by the infiltration of the LDL （low-density lipoprotein） from the flowing blood to the arterial wall.

关键词： Disturbed flow Arterial wall Mass transfer Atherosclerosis Wall shear rates

Changes in Organic Carbon Index of Grey Desert Soil in Northwest China After Long-Term Fertilization

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Journal of Integrative Agriculture 2014年第3期13卷 554-561页

作者： XU Yong-mei LIU Hua WANG xi-he XU Ming-gang ZHANG Wen-ju JIANG gui-ying Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Key Laboratory of Oasis Nutrients and Efficient Utilization of Water and Soil Resources Research Institute of Soil & Fertilizer and Agricultural Water Conservation Xinjiang Academy of Agricultural Sciences

Soil organic carbon （SOC）, soil microbial biomass carbon （SMBC） and SMBC quotient （SMBC/SOC, qSMBC） are key indexes of soil biological fertility because of the relationship to soil nutrition supply capacity. Yet it remains unknown how these three indexes change, which limits our understanding about how soil respond to different fertilization practices. Based on a 22-yr （1990-2011） long-term fertilization experiment in northwest China, we investigated the dynamics of SMBC and qSMBC during the growing period of winter wheat, the relationships between the SMBC, qSMBC, soil organic carbon （SOC） concentrations, the carbon input and grain yield of wheat as well. Fertilization treatments were 1） nonfertilization （control）; 2） chemical nitrogen plus phosphate plus potassium （NPK）; 3） NPK plus animal manure （NPKM）; 4） double NPKM （hNPKM） and 5） NPK plus straw （NPKS）. Results showed that the SMBC and qSMBC were significantly different among returning, jointing, flowering and harvest stages of wheat under long-term fertilization. And the largest values were observed in the flowering stage. Values for SMBC and qSMBC ranged from 37.5 to 106.0 mg kg1 and 0.41 to 0.61%, respectively. The mean value rank of SMBC during the whole growing period of wheat was hNPKM〉NPK_M〉NPKS〉CK〉NPK. But there were no statistically significant differences between hNPKM and NPKM, or between CK and NPK. The order for qSMBC was NPKS〉NPKM〉CK〉hNPKM〉NPK. These results indicated that NPKS significantly increased the ratio of SMBC to SOC, i.e., qSMBC, compared with NPK fertilizer or other two NPKM fertilizations. Significant linear relationships were observed between the annual carbon input and SOC （P〈0.01） or SMBC （P〈0.05）, and between the relative grain yield of wheat and the SOC content as well （P〈0.05）. But the qSMBC was not correlated with the annual carbon input. It is thus obvious that the combination of manure, straw with mineral fertilizer may be benefit to increase SOC and improve soil quality than

关键词： carbon input Haplic Calcisol long-term fertilization Quotient of soil microbial biomass carbon soil organiccarbon index