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Relationships between Phosphatidylglycerol Molecular Species of Thylakoid Membrane Lipids and Sensitivities to Chilling-induced Photoinhibition in Rice

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Journal of Integrative Plant Biology 2008年第2期50卷 194-202页

作者： Su-Qin Zhu hua Zhao jian-Sheng Liang ben-hua ji De-Mao jiao College of Bioscience and Biotechnology Yangzhou University Yangzhou 225000 China Institute of Bioengineering Nantong University Nantong 226007 China College of Life Sciences Nantong University Nantong 226007 China Institute of Agrobiological Genetics and Physiology Jiangsu Academy of Agricultural Sciences N anjing 210014 China

In an attempt to explore the relationships between phosphatidylglycerol （PG） molecular species of thylakoid membrane lipids and sensitivities to chilling-induced photoinhibition, PG molecular species, D1 protein, electron transport activities of thylakoid membrane and the potential quantum yield （FvlFm） in rice treated under middle and low photon flux density （PFD） at 11℃ were analyzed by high performance liquid chromatography, enzyme hydrolysis, gas phase chromatography （GC） and so on. Results showed that the major molecular species of PGs in rice thylakoid membrane were 18：3/16：0, 18：3/16：1（3t）, 18：2/16：0, 18：2/16：1（3t）, 18：1/16：0, 18：1/16：1（3t）, 16：0/16：0, 16：0/16：1（3t）. There were large differences in the contents of unsaturated PG molecular species such as 18：1-3/16：0-16：1（3t） and saturated PG molecular species like 16：0/16：0-16：1（3t） among japonica cv 9516 0-9516）, japonica-indica hybrid F1 j-9516/i-SY63 （ji-95SY） and indica cv Shanyou 63 （i-SY63）. J-9516 containing higher contents of unsaturated PG molecular species was manifest in stable D1 protein contents under chill and tolerant to chill-induced photoinhibition. In contrast to j-9516, i-SY63 with lower contents of unsaturated PG molecular species, exhibited unstable D1 protein contents under chill and was sensitive to chill-induced photoinhibition, ji-95SY containing middle contents of unsaturated PG molecular species between those of j-9516 and i-SY63, exhibited mid extent of sensitivity to chill-induced photoinhibition. The losses in D1 protein also account for the inhibition in electron transport activity of thylakoid membrane and the observed decline in FvlFm. The PG molecular species that is efficient in raising chilling-resistant capacity were those containing unsaturated fatty acids, namely, unsaturated PG molecular species. These results implied that the substrate selectivity of the glycerol-3-phosphate acyltransferase in chloroplasts towards 16：0 or 18：1 displayed greatly the difference between j

关键词： chilling-induced photoinhibition D1 protein molecular species phosphatidylglycerol rice.

CO2 Exchange and Chlorophyll Fluorescence of Phosphoenolpyruvate Carboxylase Transgenic Rice Pollen Lines

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Journal of Integrative Plant Biology 2006年第12期48卷 1431-1438页

作者： Li-Li Ling Hong-Hui Lin ben-hua ji De-Mao jiao Key Laboratory of Bio-resources and Eco-environment（Ministry of Education） College of Life Sciences Sichuan University Chengdu 610064 China Institute of Life Sciences Nantong University Nantong 510061 China jiangsu Academy of Agricultural Sciences 84-401 Nanjing 210014 China

To elucidate the photosynthetic physiological characteristics and the physiological inherited traits of rice （Oryza sativa L.） hybrids and their parents, physiological indices of photosynthetic CO2 exchange and chlorophyll fluorescence parameters were measured in leaves of the maize phosphoenolpyruvate carboxylase （PEPC） transgenic rice as the male parent, sp. japonica rice cv. 9516 as the female parent, and the stable JAAS45 pollen line. The results revealed that the PEPC gene could be stably inherited and trans- ferred from the male parent to the JAAS45 pollen line. Moreover, the JAAS45 pollen line exhibited high levels of PEPC activity, manifesting higher saturated photosynthetic rates, photosynthetic apparent quantum yield （AQY）, photochemical efficiency of photosystem II and photochemical and non-photochemical quenching, which indicated that the JAAS45 pollen line has a high tolerance to photo-inhibition/photooxidation under strong light and high temperature. Furthermore, JAAS45 was confirmed to still be a C3 plant by δ^13C carbon isotope determination and was demonstrated to have a limited photosynthetic C4 microcycle by feeding with exogenous C4 primary products, such as oxaloacetate or malate, or phosphoenolpyruvate. The present study explains the physiological inherited properties of PEPC transgenic rice and provides an expectation for the integration of traditional breeding and biological technology.

关键词： anther culture phosphoenolpyruvate carboxylase (PEPC) physiological inherited trait rice hybrid transgenic rice

Changes in Unsaturated Levels of Fatty Acids in Thylakoid PSII Membrane Lipids During Chilling-induced Resistance in Rice

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Journal of Integrative Plant Biology 2007年第4期49卷 463-471页

作者： Su-Qin Zhu Chun-Mei Yu Xin-Yan Liu ben-hua ji De-Mao jiao Institute of Bioengineering Nantong University Nantong 226007 China College of Life Sciences Nantong University Nantong 226007 China Institute of Agrobiological Genetics and Physiology Jiangsu Academy of Agricultural Sciences Nanjing 210014 China

Temperature is one of the abiotic factors limiting growth and productivity of plants. In the present work, the effect of low non-freezing temperature, as an inducer of ＂chilling resistance＂, was studied in three cultivars of rice （Oryza sativa L.）, japonica cv. 9516 （j-9516）, the two parental lines of superhigh-yield hybrid rice between subspecies, Peiai/E32 （ji-PE）, and the traditional indica hybrid rice Shanyou 63 （i-SY63）. Leaves of chill-treated rice showed chilling-induced resistance, as an increase of their low-temperature tolerance was measured using chlorophyll fluorescence measurements, revealing a change in photosystem II （PSII） efficiency. After 5 d of exposure to 11 ~C under low light （100 pmol·m^-2·s^-1）, levels of unsaturated fatty acids in PSII thylakoid membrane lipids decreased during the initial 1-2 d, then increased slowly and reached 99.2%, 95.3% and 90.1% of the initial value （0 d） in j-9516, ji-PE and i-SY63, respectively, on the fifth day. However, under medium light （600 μmol·m^-2·s^-1）, all cultivars experienced similar substantial photoinhibition, which approached steady state levels after a decline in levels of unsaturated fatty acids in PSII thylakoid membrane lipids to about 57.1%, 53.8% and 44.5% of the initial values （0 d） in j-9516, ji-PE and i-SY63 on the fifth day. Under either chilling-induced resistance （the former） or low temperature photoinhibition （the latter） conditions, the changes of other physiological parameters such as D1 protein contents, electron transport activities of PSII （ETA）, Fv/Fm, xanthophyl cycle activities expressed by DES （deepoxide state） were consistent with that of levels of unsaturated fatty acids in PSII thylakoid membrane lipids. So there were negative correlations between saturated levels of fatty acids （16：1（3t）, 16：0, 18：0）, especially the 16：1（3t） fatty acid on thylakoid membrane and other physiological parameters, such as D1 protein contents, ETA and （A＋Z）/（A＋V＋Z）. A specific role of desaturation o

关键词： chilling-induced resistance D1 protein rice thylakoid PSII membrane lipids unsaturated fatty acids xanthophyl cycleactivity.

Simulation and Instability Investigation of the Flow around a Cylinder between Two Parallel Walls

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Journal of Thermal Science 2015年第2期24卷 140-148页

作者： DOU hua-Shu ben An-Qing Faculty of Mechanical Engineering and Automation Zhejiang Sci-Tech University

The two-dimensional flows around a cylinder between two parallel walls at Re=40 and Re=100 are simulated with computational fluid dynamics(CFD). The governing equations are Navier-Stokes equations. They are discretized with finite volume method(FVM) and the solution is iterated with PISO Algorithm. Then, the calculating results are compared with the numerical results in literature, and good agreements are obtained. After that, the mechanism of the formation of Karman vortex street is investigated and the instability of the entire flow field is analyzed with the energy gradient theory. It is found that the two eddies attached at the rear of the cylinder have no effect on the flow instability for steady flow, i.e., they don't contribute to the formation of Karman vortex street. The formation of Karman vortex street originates from the combinations of the interaction of two shear layers at two lateral sides of the cylinder and the absolute instability in the cylinder wake. For the flow with Karman vortex street, the initial instability occurs at the region in a vortex downstream of the wake and the center of a vortex firstly loses its stability in a vortex. For pressure driven flow, it is confirmed that the inflection point on the time-averaged velocity profile leads to the instability. It is concluded that the energy gradient theory is potentially applicable to study the flow stability and to reveal the mechanism of turbulent transition.

关键词： numerical simulation cylinder energy gradient theory stability inflection point

Quantitative deformation measurements and analysis of the ferrite-austenite banded structure in a 2205 duplex stainless steel at 250 ℃

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Chinese Physics B 2018年第3期27卷 487-493页

作者： ji-hua Liu School of Mechanical Engineering Tianjin UniversityTianjin 300354China Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin UniversityTianjin 300354China

The deformation process of the microstructure in 2205 duplex stainless steel(DSS)under thermo-mechanical coupling at 250℃was investigated using digital image correlation(DIC).A thermal tension test of duplex stainless steel(2205DSS)with a banded structure was carded out to observe the initial deformation of the *** was found that inhomogeneous strain fields occurred primarily in *** maximum normal strain in austenite was almost pos-itive,while that in ferrite was almost *** addition,a thermal cyclic-loading test was conducted,and the strain field was characterized by *** heterogeneities were induced after 400 cycles,which spread within the austenite and at the phase boundaries with the load *** high tensile-strain regions were always located adjacent to regions of intense compressive *** on the strain matrix sum *** number,we found that hardening occurred in the early cycles followed by softening.

关键词： thermo-mechanical coupling duplex stainless steel digital image correlation(DIC)

Study on Quantum Entanglement Between Mesoscopic Circuit and Environment at Coherent State

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Communications in Theoretical Physics 2008年第10期50卷 897-902页

作者： ji Ying-hua College of Physics and Communication Electronics Jiangxi Normal University Nanchang 330022 China Key Laboratory of Optoelectronic ＆ Telecommunication of jiangxi Nanchang 330022 China

Taking into account the interaction between electrons and phonons, in the case without-rotating-wave aproximation, we study the entangling property between the mesoscopic circuit and environment at coherent state or equilibrium state. The result indicates that, in long time limit t →∞, the averages of charge and current in the circuit only depend on the average of the system at the initial state when the environment is initially at thermal equilibrimn. However, when the environment is initially at coherent state, the average of charge and current in the circuit is determined by the specific coherent state ensemble. Generally speaking, the entanglement between the circuit and environment will lead to the quantum state purity declining of the circuit, then the circuit emerges decoherent phenomenon, and so a mixed *** appears. Purity changes are related to the initial quantum state of environment and circuit. With the further evolution of time, coherence will be gradually restored, but cannot return to 1.

关键词： quantum state purity entanglement mesoscopic circuit environment

Hopf Cyclicity of a Family of Generic Reversible Quadratic Systems with One Center

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Acta Mathematica Sinica,English Series 2019年第10期35卷 1586-1594页

作者： ji hua WANG School of Mathematics Sun Yat-sen University

This paper is concerned with small quadratic perturbations to one parameter family of generic reversible quadratic vector fields with a simple center. The first objective is to show that this system exhibits two small amplitude limit cycles emerging from a Hopf bifurcation. The second one we prove that the system has no limit cycle around the weak focus of order two. The results may be viewed as a contribution to proving the conjecture on cyclicity proposed by Iliev(1998).

关键词： Quadratic reversible system limit cycle weak focus Hopf bifurcation

Preparation and Characterization of Thermoresponsive Hyperbranched Polyethylenimine with Plenty of Reactive Primary Amine Groups

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Chinese Journal of Polymer Science 2014年第7期32卷 961-968页

作者： hua-ji Liu Run-hua Dong 陈宇 Department of Chemistry School of SciencesTianjin UniversityCollaborative Innovation Center of Chemical Science and Engineering

Certain amount of primary amine （NH2） groups of hyperbranched polyethylenimine （HPEI） was first protected by Boc groups. Subsequently, the residual reactive amine groups were reacted with isobutyric anhydride to introduce isobutyramide （IBAm） groups to HPEI. Finally, Boc groups were deprotected to result in HPEI-IBAm-NH2 with 18% of primary amine terminals on the periphery and 80% of IBAm terminal groups （abbreviated as HPEI-IBAm0.80-NH2）. 1H-NMR characterization proved the successful preparation of the product in each step. Compared with its spatial isomer HPEI- IBAm0.8o without primary amine groups, IH-NMR spectra verified that more IBAm groups were located in the interior of HPEI-IBAm0.80-NH2. The further modification of ***-NH2 and HPEI-IBAmo.8o with p-nitrobenzaldehyde demonstrated that ***-NH2 was more reactive than HPEI-IBAm0.80 due to its possession of primary amines. Turbidimetry measurements showed that HPEI-IBAm0.80-NH2 was thermoresponsive in water. In the pH range of 9.5-10 its cloud point temperature （Top） was constant, and it increased obviously upon decreasing the pH below 9.5. The thermoresponsive HPEI-IBAmo.8 exhibited the similar trend, but the pH threshold to achieve the constant Top was around 8.5. Moreover, HPEI-IBAm0.8-NH2 showed higher Top and broader phase transition than HPEI-IBAm0.8. The mechanism leading to the different thermoresponsive properties between HPEI-IBAm0.8-NH2 and its spatial isomer HPEI-IBAm0.8 was discussed.

关键词： Hyperbranched Phase transition Polyethylenimine Spatial isomer Thermoresponsive polymers.

Probing the mechanosensitivity in cell adhesion and migration: Experiments and modeling

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Acta Mechanica Sinica 2013年第4期29卷 469-484页

作者： Bao-hua ji Bo Huo Biomechanics and Biomaterials Laboratory School of Aerospace Engineering Beijing Institute of Technology

Cell adhesion and migration are basic physiolog- ical processes in living organisms. Cells can actively probe their mechanical micro-environment and respond to the ex- ternal stimuli through cell adhesion. Cells need to move to the targeting place to perform function via cell migration. For adherent cells, cell migration is mediated by cell-matrix adhesion and cell-cell adhesion. Experimental approaches, especially at early stage of investigation, are indispensable to studies of cell mechanics when even qualitative behaviors of cell as well as fundamental factors in cell behaviors are unclear. Currently, there is increasingly accumulation of ex- perimental data of measurement, thus a quantitative formula- tion of cell behaviors and the relationship among these fun- damental factors are highly needed. This quantitative under- standing should be crucial to tissue engineering and biomed- ical engineering when people want to accurately regulate or control cell behaviors from single cell level to tissue level. In this review, we will elaborate recent advances in the ex- perimental and theoretical studies on cell adhesion and mi- gration, with particular focuses laid on recent advances in experimental techniques and theoretical modeling, through which challenging problems in the cell mechanics are sug- gested.

关键词： Cell mechanics ~ Cell adhesion. Cell migration.Modeling ~ Mechanobiology