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Lysobacter. spp. are considered as important biocontrol bacteria, due to their antagonistic activity against many pathogenic fungi, bacteria and nematodes. Rep-PCR was used to analyze the genetic diversity of 12 Lysobacter strains. These strains included Lysobacter antibioticus (HY, 13-1, 13-6, 6-B-1, 13-B-1, 6-T'-4, LJ6-3, LJ6-4 and LR9-3), Lysobacter enzymogenes (DH3, 1-T-1-4) and Lysobacter capsici (LG18) isolate from different regions in Yunnan province of China. Rep-PCR was performed using DNA amplification with primers based on short bacterial repetitive elements (ERIC, BOX, IS1113 and J3). The genetic diversity was analyzed through rep-PCR, molecular fingerprint clustering analysis and UPGMA to construct phylogenetic tree. The results show that when the genetic distance was 0.59, IS1113-PCR could cluster the Lysobacter strains as 3 species: L. antibioticus, L. enzymogenes and L. capsici. The 3 species had obvious differences between each other and the rep-PCR technique could be used to detect genetic variation between different Lysobacter strains, identification and strain classification. Key words: Lysobacter, Rep-PCR, genetic diversity.

Relaxation oscillations are ubiquitous in various fields of natural science and engineering technology. Exploring possible routes to relaxation oscillations is one of the important issues in the study of relaxation oscillations. Recently, the pulse-shaped explosion (PSE), a novel mechanism which can lead to relaxation oscillations, has been reported. The PSE means pulse-shaped sharp quantitative changes related the variation of system parameters in branches of equilibrium points and limit cycles, which leads the system’s trajectory to undertake sharp transitions and further induces relaxation oscillations. Regarding externally and parametrically excited nonlinear systems with different frequency ratios, some work on PSE has been reported. The present paper focuses on the PSE and the related relaxation oscillations in a externally and parametrically excited Mathieu-van der Pol-Duffing system. We show that if there is an initial phase difference between the slow excitations with the same frequency ratio, the fast subsystem may compose of two parts with different expressions, each of which determines a different vector field. As a result, the bistable behaviors are observed in the system. In particular, one of the vector fields exhibits two groups of bifurcation behaviors, which are symmetric with respect to the positive and negative PSE, and each can induce a cluster in the relaxation oscillations. Based on this, we present several routes to compound relaxation oscillations, and obtain new types of relaxation oscillations connected by pulse-shaped explosion, which we call compound “subHopf/fold-cycle” relaxation oscillations and compound “supHopf/supHopf” relaxation oscillations, respectively. Our results show that the two clusters in the resultant relaxation oscillations are connected by the PSE, and the initial phase difference plays an important role in transitions to different attractors and the generation of relaxation oscillations. Although the research in this paper is based on a specific nonlinear system, we would like to point out that the bistable behaviors, the PSE and the resultant compound relaxation oscillations can also be observed in other dynamical systems. The reason is that the fast subsystem composes of two different vector fields induced by the initial phase difference, which dose not rely on a specific system. The results of this paper deepen the research about PSE as well as the complex dynamics of relaxation oscillations.

Colorectal cancer (CRC) is the third most commonly diagnosed cancer. Celastrol exhibits anti-tumor activities in a variety of cancers. However, the effect of Celastrol on human CRC and the underlying mechanisms still need to be elucidated. The present study aimed to use in vitro and in vivo methods to clarify the anti-tumor effect of Celastrol and use protein microarrays to explore its mechanisms. We demonstrated that Celastrol effectively inhibited SW480 CRC cell proliferation. Two weeks of Celastrol gavage significantly inhibited the growth of xenografts in nude mice. A total of 69 candidate proteins were identified in the protein microarray experiment, including the most highly enriched protein Shoc2, which is a scaffold protein that modulates cell motility and metastasis through the ERK pathway. Celastrol significantly inhibited ERK1/2 phosphorylation in cell lines and xenograft tumors. Down-regulation of Shoc2 expression using Shoc2 siRNA also inhibited ERK1/2 phosphorylation. Furthermore, down-regulation of Shoc2 expression also significantly inhibited proliferation, colony formation, and migration functions of tumor cells. In addition, the LD0 of Celastrol by gavage is equal or more than 80 mg/kg in C57 male mice. In summary, we unraveled the anti-CRC function of Celastrol and confirmed for the first time that it inhibited the ERK1/2 pathway through binding to Shoc2.

Using hourly averaged data of > 2 MeV electron fluxes measured with GOES 7/9/10/11 satellites during 1988–2010, this paper investigates statistically conditions of solar wind and geomagnetic activities during relativistic electrons flux (Fe) enhancements, and describes the dependence of relativistic electrons at geosynchronous orbit (GEO) on local time, magnetic storms. The results are as follows: (1) The local time dependence of GEO relativistic electrons is influenced by solar wind and geomagnetic activities. The noon/midnight electron flux ratio grows with increasing solar wind velocity (Vsw). On conditions of the Dst index above −50 nT, relativistic electrons show regular variation with local time, while during storms with Dst Femax ≥ 103 pfu exhibited no such solar cycle and seasonal dependences. For most intense events, relativistic electron fluxes begin to increase during main phases of magnetic storms, while for weaker events, relativistic electron fluxes tend to increase during recovery phases. (3) The solar wind density shows as a good indicator of subsequent relativistic electron activities. For most electron flux enhancement events, relativistic electron flux decreased to its minimum after 0∼1 days of the maximum solar wind density, Nmax, while approaching the maximum after 0∼2 days of the minimum solar wind density, Nmin. (4) Above 90% of relativistic electron events occurred on conditions of high-speed solar wind and geomagnetic disturbances, which are as follows: Vswmax > 516 km/s, Dstmin 14.1 cm−3, Bzmin 698 nT. (5) For all magnetic storms, occurrence probability of daily maximum electron flux above 103 pfu after Dstmin, is about 53%, the percent of intense, weak events being 36%, 64%, respectively, which is hardly affected by intensities of storms. During storms, solar wind velocity, density, and the AE index are important indicators for subsequent relativistic electron activities.

A photon imaging system with single photon detecting and imaging capabilities is constructed and a detection method based on pipeline filtering is proposed to detect the stationary point target under a photon limited condition.The stationary point target detection method based on pipeline filtering is studied on the characteristics of position and noise for stationary point targets in photon images.The diameter of pipeline filter is optimized to reduce the false alarm rate.The relationships of detection performance with the number of signal photons and noise photons,the pipeline length and the detection threshold are explored through photon image sequences.For the image sequence with the average incidences of signal and noise of 0.4 and 5.215 respectively,the detection rate can be more than 0.9 and the false alarm rate less than 0.08 when the pipeline length is 9 and detection threshold is 2.The conclusion from experimental results is that the detection rate is mainly affected by the number of signal photons and the false alarm rate is dependent on the number of noise photons.

A novel method of choosing threshold range,which bases on the criterion that the mean value and the variance are equal in Poisson distribution,is proposed to eliminate the background noise in photon images.Point process analysis method is used to study the statistical properties of point target under the photon limited condition and verify the results experimentally.The results show that the detection statistics of point target under the photon limited condition subject to a stationary Poisson point process.Through the point process analysis method,the expectation occurrence-rate of ultra-weak target and the recurrence probability in the follow period can be obtained quickly,which lay the foundations for detection,tracking and location forecasting.

The vibration spectrum of quasi 1D (one dimensional) nanosize lines was calculated using the density function theory (DFT)/B3LYP method at 6-31G(d) level.The results showed that the vibration frequency and intensity of IR and Raman spectra obviously indicated even-odd oscillation with the number of SiO_2 units.For different vibration modes,the even-odd oscillation was strong or weak because of the effect of the polar group's orientation relative to silicon-oxygen two-member ring.Moreover,the analyses of the polarization indicated the effect of hydroxyl on even-odd oscillation.

By analyzing the WWW Cache model, we bring forward a user-interest description method based on the fuzzy theory and user-interest inferential relations based on BP (back propagation) neural network. By this method, the users' interest in the WWW cache can be described and the neural network of users' interest can be constructed by positive spread of interest and the negative spread of errors. This neural network can infer the users' interest. This model is not the simple extension of the simple interest model, but the round improvement of the model and its related algorithm.

The main purpose of this study is to investigate the characteristics as well as the bifurcation mechanisms of the bursting oscillations in the asymmetrical dynamical system with two scales in the frequency domain. Since the slow-fast Hodgkin-Huxley model was established to successfully reproduce the activities of neuron, the complicated dynamics of the system with multiple time scales has become a hot research topic due to the wide engineering background. The dynamical system with multiple scales often presents periodic oscillations coupled by large-amplitude oscillations at spiking states and small-amplitude oscillations at quiescent states, which are connected by bifurcations. Up to now, most of the reports concentrate on bursting oscillations in the symmetric systems, in which there exists only one form of spiking oscillations and quiescence, respectively. Here we explore some typical forms of bursting behavior in an asymmetrical dynamical system with periodic excitation, in which there exists an order gap between the exciting frequency and the natural frequency. As an example, based on the typical Chua's oscillator, by introducing an asymmetrical controller and a periodically changed current source, and choosing suitable parameter values, we establish an asymmetrical dynamical system with two scales in the frequency domain. Since the exciting frequency is much smaller than the natural frequency, the whole periodic exciting term can be regarded as a slowly-varying parameter, leading to the fast subsystem in autonomous form. Since all the equilibrium curves and relevant bifurcations are presented in the form related to the slowly-varying parameter, the transformed phase portraits describing the evolution relationship between the state variables and the slowly-varying parameter are employed to account for the mechanism of the bursting oscillations. With the variation of the slowly-varying parameter, different equilibrium states and relevant bifurcations in the fast subsystem are presented. It is found that for different parameter values, multiple balance curves of the fast subsystem may coexist, which affect the structure of the bursting attractor. For the other parameters fixed to certain values, the balance curve with the variation of the slowly-varying parameter is presented. Three typical cases with different exciting amplitudes are considered, corresponding to different situations of coexistence of equilibrium states in the fast subsystem. In the first case, there exist at most three stable equilibrium points in the fast subsystem. Bursting attractor that oscillates around the three points can be observed, in which fold and Hopf bifurcations lead to the alternations between spiking states and quiescent states, while in the second case, saddle on the limit cycle bifurcation may cause the repetitive spiking oscillations to jump to the equilibrium curve. In the third case with relatively large exciting amplitude, only two equilibrium curves may involve the bursting oscillations, in which fold bifurcations lead to the alternation between the quiescent states and spiking states. Unlike the structures of bursting oscillations in the symmetric system, different forms of asymmetrical bursting oscillations with different periodic exciting amplitudes can be observed, the mechanisms of which are presented. It is pointed out that the change of the external exciting amplitude, does not only cause the variation of the attracting basins corresponding to different stable equilibrium branches, but also leads to the change of the temporal intervals when the trajectory passes different bifurcation points, respectively, which results in different patterns of bursting oscillations. Furthermore, since the slowly-varying parameter determined by the whole exciting term changes between two extreme values determined by the amplitude, the trajectory of the bursting oscillations of the transformed phase portrait returns at the two extreme values. The properties of equilibrium branches between the two extreme values determine the forms of the moving attractors.

This paper analyzes the relationship between rural finance of Sichuan Province and the rural economy from 1999 to 2009 by using the sequential growth rate of the total value of farming, forestry, animal husbandry and fishery and the sequential growth rate of the per capital total income of rural households as the indicators of rural economic development; and taking the volume of deposit, volume of credit, volume of agricultural credit and the credit volume of township enterprises as the indicators of rural financial development; as well as the method of grey correlation analysis. The results show that there is an obvious positive correlation between them, and the development of country finance has the closest connection with the sequential growth rate of farming, forestry, animal husbandry, sideline production and fishery. The loan scale of township enterprises has the biggest influence on the increase of the rural economy. The countermeasures are put forward, covering optimizing investment structure; supporting the development of township enterprises; encouraging loan; actively lightening the financial difficulties in the process of developing rural economy; innovating and exploring; and promoting the diversified development of rural finance.

Tissue culture ofAntirrhium majus was experimented by using the tip of shoots as the explants, and comparing the effects of NAA, IAA and 2, 4-D on the formation of adventitious buds. The results indicated that the effect of NAA was the best for the formation of adventitious buds, 5.0, 7.0, 9.0, 11.0, 13.0 mg/L BA combinatcd with 0.1, 0.5, 1.0, 1.5, 2.0 mg/L NAA respectively. The results show that combinations of the concentrations of BA 7.0–9.0 mg / L and NAA 0.1–0.5 mg/ L were advantageous to the regeneration of buds and NAA was very important for callus growth.