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Table of Content

      
    16 May 2009
    Volume 44 Issue 5
    Articles
    Effects of hypoxia training on skeleton muscle HIF1α gene expression in rats
    J4. 2009, 44(5):  1-9. 
    Abstract ( 762 )   PDF (739KB) ( 850 )   Save
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    The purpose of this study is to probe into the effects of different hypoxia training methods on skeleton muscle HIF1αmRNA in rats, in order to provide theoretical and applying basis for the application of hypoxia training to sports training. 90 rats are selected from 120 male SD rats (6 weeks old) by three weeks adaptable training and exhaustive test . These rats were randomly divided into 9 groups: normoxia quiet control group(C), continuing hypoxia group(CH), intermittent hypoxia group(IH), normaxia training group(T), livinghigh and traininghigh group(HiHi), livinghigh and traininglow group(HiLo), livinglow and traininghigh group(LoHi), normoxia training group after HiHi and normoxia training group after HiLo. During the 6 weeks of experimental period, we employed the 13.6% concentration of oxygen (equal to altitude of 3?500?m) in the hypoxic chamber. The rats of hypoxia training were introduced to treadmill. The training speed was 30?m/min in hypoxia and 35?m/min in normoxia. The rats were trained 5?d/week and were sacrificed after 6 weeks. Technology of RQPCR, immunohistochemistry andWestern blot are adopted in order to test the mRNA and protein level changes of  HIF1αin rats′ skeletal muscle to probe further into the mechanisms of the acclimatization in skeletal muscle. It is found that the mRNA level of HIF1α in rat skeletal muscle increased significantly (P<0.05) in HiHi and HiLo comparing with LoLo; and the mRNA level of HIF1α (1.05 times) in rat skeletal muscle increased significantly (P<0.01) in HiHi comparing with C group. Comparing with LoLo group, the mRNA level of HiHi and HiLo increased significantly. The mRNA level of HIF1α declined significantly in T group after HiHi and HiLo(P<0.05). The results show that the mRNA level of HIF1α in rat skeletal muscle increased significantly in HiHi, HiLo and CH. Moreover,the level of HIF1α is closely related to the extend of hypoxia and the exposure time.

    Cloning and prokaryotic expression of myeloperoxidase gene in mandarin fish, Siniperca chuatsi
    J4. 2009, 44(5):  10-19. 
    Abstract ( 706 )   PDF (4239KB) ( 838 )   Save
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    Myeloperoxidase (MPO) is widely distributed in phagocytes of vertebrates, which mainly functions in catalysing chloride and hydrogen peroxide to produce hypochlorous acid, a potent antimicrobial agent in polymorphonuclear neutrophils. Currently, little is known about MPO of fish and other lower vertebrates. In the present paper, the fulllength cDNA of MPO was cloned from mandarin fish by utilizing reverse transcriptasepolymerase chain reaction and rapid amplification of cDNA ends. The results showed that the fulllength of mandarin MPO cDNA was 3?345 nucleotides (nt), with an open reading frame of 2292 nt encoding 763 amino acids. Although amino acid sequence comparison of MPO of mandarin with those of mammals demonstrated that their similarity (64%~65%) was not very high, their molecular weights were quite approximate. Like mammals, the MPO of mandarin fish also posessed one hemachrome group, one conserved banding calcium site, six intramolecule disulfide bridges and six Nglycosylation sites, implying that it may function as same as its mammalian counterpart. On the other hand, partial cDNA sequence of mandarin MPO was expressed in Escherichia coli rosettagami (DE3) using a recombinant expression plasmid pETMPO, and the combinant protein was purified by the Ni2NTA resin using it's Nterminal HisTag.

    Investigations on survival competitiveness and gene flow of
    transgenic cotton with beta/als gene in the field
    J4. 2009, 44(5):  20-27. 
    Abstract ( 752 )   PDF (751KB) ( 1055 )   Save
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    T3 and T4 homozygous lines of transgenic cotton, which was transformed with the betA gene coding for choline dehydrogenase from E. coli and the als gene coding for acetolactate synthase, were used for the study of biological characteristics and gene flow in the field. The results showed that some agronomic traits concerning with the survival competitive power of  the transgenic cotton with betA/als were significantly improved compared with the control of wild type lines Lumianyan19, such as reproductive capacity of seeds, seed vigor after storage and economic yield in salinealkali soil, while the value of micronaire was decreased. The other agronomic traits of the two kinds of cotton were resembled. One of the transgenic character obtained, resistance to herbicide, could be inherited stably and expressed well in the field. In the transgenic cotton release region with the area 6?m×6?m, the frequency of als gene introduced into the wild type cotton was reduced rapidly as the distance from the nontransgenic area to the release area increasing. Thus, making proper isolation distance (>200?m) could avoid the occurrence of exogenous gene escape. Yet some uncertain factors such as insects' effect on pollen spread should be considered before setting up the isolation area, and the isolation distance should be increased properly.

    Isolation and classification of a Streptomyces netropsis strains SD07 which produces polyene macrolide antibiotics with
     broadspectrum  and high antifungal activity
    J4. 2009, 44(5):  28-32. 
    Abstract ( 940 )   PDF (704KB) ( 965 )   Save
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    Streptomyces sp. SD07 was isolated from the soil of the mountain area in the south of Jinan, Shandong province. This strain exhibited broadspectrum and high antifungal activity. Based on the results of preliminary morphological, cultural, physiological and biochemical studies on this strain, and its 16S rDNA sequences, strain SD07 was classified as Streptomyces netropsis. The antifungal compounds CASD07 were extracted from the mycelia and then crystallized,named as CASD07. CASD07 could inhibit many fungi such as Ascomycetes, Basidiomycetes, Zygomycetes and so on. The data from ultravioletvisible absorption and highperformance liquid chromatography / diode array detection (HPLC / DAD) indicated that CASD07 was a mixture of pentaene macrolide and heptaene macrolide antibiotics, and the major compounds were pentaene macrolide antibiotics. CASD07 has wider antifungal spectrum and higher antifungal activity(about two times Amphoteric B).

    Pnitroaniline biosorption by a novel exopolysaccharide from the deepsea mesophilic bacterium Wangia profunda (SMA87)
    J4. 2009, 44(5):  33-39. 
    Abstract ( 705 )   PDF (538KB) ( 843 )   Save
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    Biosorption of pnitroaniline by exopolysaccharide (EPS) from the deepsea mesophilic bacterium Wangia profunda (SMA87) was studied. The SMA87 EPS were respectively characterized by DSC/TGA, FTIR and Zeta potential. The influence of contact time,SMA87 EPS dosage, pH and temperature were investigated by batch adsorption experiments. The results showed that SMA87 EPS was particularly effective at removal pnitroaniline from aqueous solution. The adsorption ratio of pnitroaniline could reach 91%, under the condition of 20?℃, pnitroaniline concentration of 15?mg/L, EPS dosage of 01?g/L and equilibrium time at 120?min. The equilibrium data at different temperatures fitted all the Langmuir, Freundlich and RedlichPeterson models well. The maximum adsorption capacity of pnitroaniline was calculated to be 7692?mg/g (30?℃) according to the Langmuir model. Compared with the pseudofirstorder kinetic model, the biosorption kinetics for pnitroaniline can be well described by the pseudosecondorder kinetic model.

    Study on the determination method of total flavonoids in ginkgo biloba extract
    J4. 2009, 44(5):  40-44. 
    Abstract ( 1169 )   PDF (315KB) ( 920 )   Save
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    A simple and sensitive new method for the determination of total flavonoids in ginkgo biloba extract was put forth. The experiment results indicated that the fluorescence intensity of ginkgo biloba extract (GBE) was greatly enhanced by heating in an acid medium and forming complex with Al3+. A fluorimetric method for determination of total flavonoids in GBE was proposed by taking quercetin as standard sample. Under the optimum conditions, a linear relationship was obtained between the fluorescence intensity and the concentration of quercetin in the range of 0000?75~050?μg/mL(R=0999?9; P<0000?1), and the detection limit was 045?ng/mL(S/N=3). This method was applied for determining the total flavonoids in GBE, the recovery test was put forth by standard addition method, and the satisfied results were obtained.

    Research of the threedimensional electrical impedance tomography based on the cylinder model
    J4. 2009, 44(5):  45-48. 
    Abstract ( 682 )   PDF (715KB) ( 825 )   Save
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    The electrical impedance tomography technique is studied with the thorax model, and the threedimensional cylinder model is built. The forward pr

    oblemis completed by finite element method. The potential on the edge reflects the change of the internal impedance. The inverse problem is analyzed by the modefied NewtonRaphson algorithm based on homotopy theory. The impedance distribution is obtained in the inverse problem which approaches the true one. It shows that this mothod is suitable for the inverse problem of the electrical impedance tomography.

    Adaptive multistage SLM scheme for PAPR reduction in OFDM system
    J4. 2009, 44(5):  49-55. 
    Abstract ( 857 )   PDF (353KB) ( 948 )   Save
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    Based on selected mapping (SLM) for peaktoaverage power ratio (PAPR) reduction in OFDM system, an improved version, named adaptive multistage selected mapping (AMSLM) is proposed. By using different phase weighting factor set and selected mapping in each stage, the property of correlation of candidate vectors in  different stages is reduced, which improves the PAPR performance. Moreover, with the purpose of reducing the computational complexity, a proper threshold is introduced, where if the minimum value of PAPR obtained in current stage is higher than the threshold, the optimization process for next stage will continue; otherwise, the whole optimization process will be terminated. Simulation results show that, compared with SLM, proposed AMSLM scheme has almost the same or better performance in PAPR reduction. Meanwhile, the computational complexity is reduced dramatically, where AMSLM with four stages outperforms SLM by 4781% in computational complexity.

    Study on guaranteed cost control problems for a class of discrete impulsive switched  system with time delays and parameter uncertainty
    J4. 2009, 44(5):  56-61. 
    Abstract ( 814 )   PDF (367KB) ( 787 )   Save
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    Guaranteed cost control problems are investigated for a discrete impulsive switched system with normbounded parameter uncertainty and invariant time delays. A new quadratic cost index is introduced for the given system. Based on Lyapunov theory and the linear matrix inequality (LMI) techniques, a sufficient condition for the existence of guaranteed cost state feedback controller of discrete impulsive switched systems is derived in discrete domain. The sufficient condition is equivalent to the LMI solvability problem and the feasible solutions provide a parameterized representation of the performance bound. Finally, a numerical example illustrates  the validity of the proposed method.

    Study on conditions for the existence of bound states in central field with variational method
    J4. 2009, 44(5):  62-66. 
    Abstract ( 715 )   PDF (203KB) ( 717 )   Save
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    In quantum physics, variational method can be used to study the conditions for the existence of bound states in a central field. We take the following six kinds of potentials, V1(r)=-V0a δ(r-a), V2(r)=-V0e-r/a, V3(r)=-V0ae-r/a/r, V4(r)=-V0e-r2/a2, V5(r)=-e2/r, and V6(r)=-A/r2 as examples to demonstrate the usage of this method. The derived conditions for V1 to V4 are μγa2/2>068,084,1,195 respectively; for V5, the bound states can exist for e with arbitrary value, while for V6, there is no bound states for any value of A. We also get the precise conditions by solving the Schroedinger equation for these potentials. A comparison of the results obtained by these two methods shows that the conditions derived by the variational method are sufficient, but not necessary conditions.

    Global qualitative analysis of a new SIR epidemic disease model with vertical transmission and pulse vaccination
    J4. 2009, 44(5):  67-73. 
    Abstract ( 674 )   PDF (273KB) ( 772 )   Save
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    An SIR epidemic disease model with saturated incidence rate and pulse vaccination is constructed. Based on  analysis of the model in constant cruitment and vertical transmission conditions, an infectionfree periodic solution is obtained, and the analysis of global stability of the infectionfree periodic solution is given. Also, the sufficient condition for permanence of the systemis obtained.

    A unified hybrid dynamic model for inventory systems
    J4. 2009, 44(5):  74-80. 
    Abstract ( 788 )   PDF (513KB) ( 929 )   Save
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    On the basis of hybrid dynamic system theories, a new and unified hybrid dynamic model for real inventory systems is proposed. The hybrid dynamic model evolves continnousvariable state spaces and discrete transitions, and this model characterices their changes and their interacting collection. This new model has strong capacity  because it could capture all kinds of discrete phenomena in inventory systems, and subsumes all previous models for inventory systems.

    Existence and iteration of monotone positive solutions to a class ofpLaplacian multipoint boundary value problem
    J4. 2009, 44(5):  81-85. 
    Abstract ( 838 )   PDF (209KB) ( 616 )   Save
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    A class of pLaplacian multipoint boundary value problem is studied. By using monotone iterative technique, we obtain the existence of monotone positive solutions for the boundary value problem and establish corresponding iterative schemes which are feasible and effective since they are started by constants or lineral functions. We also apply the results to a detailed example which validates our results.

    Successive iteration of positive solutions for some SturmLiouvillelike boundary value problems with pLaplacian on infinite intervals
    J4. 2009, 44(5):  86-90. 
    Abstract ( 736 )   PDF (204KB) ( 717 )   Save
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    The existence and successive iteration of positive solutions for boundary value problems with pLaplacian on infinite intervals are investigated  and the corresponding iterative schemes for approximating the solutions are also given.

    Multiplayer dynamic discrete oligopoly model for Chinese electricity market
    J4. 2009, 44(5):  91-96. 
    Abstract ( 669 )   PDF (729KB) ( 573 )   Save
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    Based on the fact that the competitions in Chinese electricity markets are oligopolistic competition,  a multiplayer dynamic discrete oligopoly model is established  then the Nash equilibrium and the system’s stability are analized. The effects and the relationship of decisions of these oligopolists are also discussed. Computer simulation has been used for the analysis the effects of parametes.