Abstract:We derive the a posterior error estimate for an energy-based atomistic/continuum method for a one-dimensional periodic chain with multi-body interactions. The current extends previous results by eliminating the requirement that the computational nodes in the continuum region coincide with the lattice sites and providing a thorough stability analysis. Based on the estimator, we design an adaptive refinement algorithm which produces the optimal convergence rate. We also show numerically that error estimator is efficient.

Abstract:By means of convergence, We introduce quasicontinuous sapces and meet-continuous sapces based on directed spaces. The main results we obtain are as follows: (1) A T_0 space is quascontinuous if and only if it is locally strongly compact if and only if its open set lattice is a hypercontinuous complete lattice if and only if it soberfication is a quasicontinuous dcpo. (2) A directed space is meet-continuous iff its closed set lattice is a frame. (3) A T_0 space is a c-space if and only it is quasicontinuous and meet-continuous.

Abstract:Error distance plays an important role in the decoding of standard Reed-Solomon codes. In 2012, Hong and Wu proposed a famous conjecture of standard Reed-Solomon codes on error distance. In this paper, We show that some polynomials of degree $q-4$ can not define deep holes over finite fields with odd characteristic by using the quadratic form and the generator matrix of maximum distance separable codes. In fact, we partially proved error distance conjecture of standard Reed-Solomon codes.

Abstract:In this article, we consider the long-time behavior of solutions for the nonlinear evolution equation with nonlinear damping. Within the theory of process on time-dependent spaces, by using the contractive functions and more detailed estimates, we prove the existence of the time-dependent attractor for the nonlinear evolution equation with critical nonlinearity.

Abstract:Firstly, Black-Scholes option pricing formula is introduced, and the importance of volatility in option pricing is analyzed. Volatility is a critical parameter for option pricing, and option prices are very sensitive to volatility's fluctuation. Then when computing particle's position and velocity, the particle swarm optimization algorithm with the adjustment of global best position is proposed according to these history data of global best positions and mutation operation. Finally, the adjusted particle swarm optimization algorithm is used to look for the approximate value of volatility in European call option on a futures contract in numerical experiments. And compared with related experiment results, the modified algorithm displays better in convergence.

Abstract:Anomalous diffusion of a fractional harmonic oscillator driven by both thermal noise and additive impulsive noise is investigated. By using the Laplace and double Laplace transform techniques, the mean, variance, correlation function and mean square displacement (MSD) of the oscillator are expressed by generalized Mittag-Leffler functions with three parameters. Furthermore, asymptotic diffusive behavior of the oscillator is investigated in terms of the asymptotic properties of generalized Mittag-Leffler function. It is shown that the impulsive noise enhances the ballistic diffusion of the oscillator for short time-lag and adds a constant to the mean square displacement for long time-lag.

Abstract:In this paper,we consider a controlled forward stochastic Stokes system with a diagonal matrix as the coefficient of diffusion term,and the diagonal matrix elements are the same bounded stochastic process.For the situation that only one control applied to the drift term,we use the Lebeau-Robbiano type spectral inequality to establish a “partial” observability estimate result,by which we get the the corresponding finite dimensional null controllability and establish the required decay estimate.Finally we derive the null controllability of the forward stochastic Stokes system.

Abstract:In order to improve the precision of Down-and-Out discrete barrier option pricing problem and reduce the computational complexity, this paper presented a Romberg method for solving partial differential Brown model with discrete time parameters. Firstly, we modeled the Down-and-Out discrete barrier option as the geometric Brownian motion model with time varying parameters, for partial differential equations used the corresponding time transform and time independent (PDE) option pricing. Then, the time independent partial differential equation is transformed into a simple form of heat conduction equation, and the model is simplified; Finally, the Romberg model is used to solve the discrete barrier option Brownian model. The experimental results verify the effectiveness of the proposed method.

Abstract:Multiple sensor measurement fusion can strip away the shortcomings of a single source which the information is not comprehensive in the process of radar track fusion. Weighted average fusion is widely used. The weighted average fusion of traditional and weights fixed can only combine with information from multiple sensors, but not pick out better information adaptively. Therefore, this paper suggests changing the fixed weight to dynamic weight. Before every fusion, calculating simple arithmetic average of multiple sensor measurements, then performing Kalman filter. Making the measurements subtract the values from Kalman filter. That is equivalent to make prediction for distinguishing data of stand or fall. And the dynamic weight is inversely proportional to the value using for prediction. Finally, the simulation experiments prove that the method in this paper can improve the precision of the fusion of target significantly.

Abstract:Face alignment method has greatly improved with using cascade regression, however due to the complexity of designing cascade regressors, the limitation of hand-crafted features make it difficult to find a better solution for face alignment task, especially with the big gesture, exaggerated expressions. Therefore, this paper proposes a novel method based on local shape constraint to solve this problem. Firstly it initializes the whole face shape by using deep convolutional neural networks (DCNN), secondly divides face into different regions according to the local regional homogeneity, defining each region constraints on local shapes, Finally takes the whole shape estimation as global constraints, combines each local shape constraints for facial feature point regression. The experiments show that our method based on local shapes constraint results in a strong improvement over the current state-of-the-art.

Abstract:In recent years, the deep packet inspection technology and traffic identification technology based on the statistical characteristics of data packet have developed rapidly. But they have some disadvantages. The deep packet inspection technology can’t identify the encrypted network traffic, and the other technology heavily relies on subjectively chosen statistical features. A network traffic identification method based on convolutional neural network algorithm is proposed in this paper. According to certain rules, the network data is converted to gray images. In order to improve the recognition rate, the original network data is extended according to the order of the TCP packets and the disorder of the UDP packets. Experimental data shows that this method has a high detection rate both in the application and application layer protocol.

Abstract:Taking the complex network as the background, and based on the Lyapunov stability theory, this paper firstly studies the asymptotic synchronization of globally coupled network, for which a new four-wing chaotic system is a node. Secondly, as a node, the four-wing chaotic system is applied to secure communication by chaos cover. Thirdly, Gaussian noise is added to cause noise interference, and the signal will be de-noised by wavelet analysis theory. Lastly, the result of numerical calculation with Matlab demonstrates that useful signals will be restored well after the wavelet threshold de-noising.

Abstract:In some license plate character recognition occasions, strong noises such as uneven cutting，strong illumination contrast and occlusion are inevitable. To solve this problem effectively, a character recognition algorithm based on Caffe deep learning framework was proposed in this paper. The convolutional neural network was built in the Caffe framework, and the network parameters were trained to obtain a network structure with high accuracy and robustness. Experiment results showed that the proposed algorithm has obvious advantages, the average recognition rate was about 5% higher when compared with the traditional digital character recognition method. And when there are strong noise pollution exists, the recognition results are better

Abstract:The modeling of interval neural network is not only a component of interval control, but also an important role to improve the robust of systems. An adaptive algorithm of momentum factor is proposed to solve the problem of slow convergence speed on the interval neural network. In this paper, interval calculation method is used to establish the mapping model of input and output variables. By introducing a momentum term with adaptive characteristics, the steepest descent algorithm is applied to update the adaptive momentum factor. Compared with the traditional method, this method not only accelerates the convergence speed, but also overcome the disadvantages of the system steady state error and easily to fall into local minimum. According to the nonlinear experiments, interval neural networks are able to establish the zone models, and the algorithm of adaptive momentum factor increase the overall performance of the network. Classic bench mark experiments show that our work can more accurate to establish interval network model, while introducing of adaptive momentum factor algorithm also can improve the overall performance of the interval neural network

Abstract:A novel design of a 1×2 and a 2×2 circularly polarized (CP) microstrip patch antenna arrays is presented in this paper. The two CP antenna arrays are fed by sequentially rotated coplanar waveguide (CPW) to slotline networks. The mechanism of circular polarization in this design is explained and the measured results shows that this kind of CPW feeding network is a good method to improve both the impedance bandwidths and 3-dB axial ratio bandwidths of CP antenna arrays. The simulated and measured impedance bandwidths and 3-dB axial ratio bandwidths of the 1×2 linear array are 3.79％ and 16.41％. Moreover, The simulated and measured impedance bandwidths and 3-dB axial ratio bandwidths of the 2×2 array are 3.61％ and 10.83％.

Abstract:The layout of hydraulic pipelines is an important step in the design of a hydraulic system.For machine tools which have a complicated assembly model, manual routing takes a lot of time. But there still exist some problems in the automatic routing module in three-dimensional design software. Those modules are not universal and the shapes are nonintuitive. Besides, the system are not easy to operate. To solve those problems, a 3D Automatic system for hydraulic pipelines on machine tools is developed. By using SolidWorks platform and VB.NET environment, the parametric design for models of pipeline spare parts is implemented based on secondary development principles and database technology. The intelligence layout for pipelines is implemented by using dynamic programming method and A-Star algorithm. Besides, a table is provided in the program to present the data for length of pipelines. The program is easy to operate, which effectively decrease workload for designing and shorten the design cycle.

Abstract:The structure and electronic structure properties of GaN doped with Mg are studied by plane-wave pseudopotential density functional theory method. By calculating the binding energy of systems with Mg replacing the Ga and N atoms respectively, it is easier for Mg atoms to replace the Ga atoms, which is consistent with the results of others. The lattice constants a and c are slightly increased after doping, and the case under high pressure is similar. With the pressure increasing from 0 GPa to 20 GPa, the band gaps of the GaN and the doped-GaN increase by about 39.1% and 38.4%, respectively.

Abstract:The structural, elastic and thermal properties of MgGeP2 crystal have been studied comprehensively with the first-principle based on the density function theory. The equilibrium lattice constant, the energy gap, the elastic coefficient and other related thermal parameters of MgGeP2 have been discussed in this paper. The results are analyzed theoretically and show that the compound of MgGeP2 at zero-pressure is direct band-gap semiconductor and the value of energy gap is 1.522eV. Furthermore, Calculation of elastic properties in this crystal indicates the MgGeP2 is an anisotropic and ductile material. In addition, the effect of temperature and pressure thermal properties such as Debye temperature, the thermal expansion coefficient, the heat capacity Cv and Cp are also worked out by the quasi-harmonic Debye model in the rang of 0~40GPa and 0~800K.

Abstract:The DFT(B3LYP) method with Aug-cc-pvtz basis set is used to investigate the equilibrium structures, atomic charge distributions, dipole moments, harmonic frequencies and total energies of CO molecule under different external electric fields. The results show that the bond length is in excellent agreement with the experimental results. The bond lengths are proved to be increasing and harmonic frequencies are proved to be decreasing, the total energy is found be first decreasing, and then increasing, with the variation of external field, and the dipole moments are detected to be increasing (Numerical results) with the variation of reverse external field. The potential energy curves of CO molecule under different external fields are also obtained by DFT(B3LYP) method with Aug-cc-pvtz basis set. The potential energy function without external electric field is fitted by Morse potential. It is found that the fitting parameters are good agreement with experimental values. The potential energy curves without external electric field is smaller than with external electric field.

Abstract:we calculate the equilibrium geometry structure of OCN2 by using B3LYP, B3p86, B3pw91 and MP2 methods combining  with cc-pVnZ (n=D,T) and aug-cc-pwCVDZ basis sets. On this base, we obtain the spectroscopic constants and anharmonic force field of OCN2. Then we compared the results of equilibrium geometry structures, rotational constants, vibration-rotation interaction constants that we obtained from the calculation with the relevant experiment and theoretical data. In addition, we also predict the quartic and sextic centrifugal distortion constants, coliolis constants, third-order and forth-order force constants of OCN2.

Abstract:A class of higher dimensions disturbed breaking solitary equation is studied using the travelling wave transformation and perturbation theory. Firstly, from a travelling wave transformation, the higher dimension problem changes to one dimension problem. Next, the corresponding typical breaking equation is considered, and its exact solitary solution is obtained by using the undetermined coefficients projectile method. Then, using the perturbation method, the solitary travelling wave asymptotic solution to a disturbed breaking equation is found. Finely, it illustrate that, the obtained asymptotic solutions are simple and valid by using this method. And In this paper, the method has a universal significance. It also used for nonlinear physics and other physical problems.

Abstract:The electronic and magnetic properties of ZnS nanowires doped with Cu atoms are comparatively studied in terms of the first-principles calculation. The formation energies of doped nanowires are smaller than that of the pristine one, indicating that the doing process is an exothermic reaction. The calculation shows Cu atom preferring to the surface position. The electronic structures show that ZnS doped with Cu atoms are the half-metallic ferromagnetic semiconductors and have important applications in spintronics.

Abstract:We used nuclear binding energy analytical formulas based on two nuclear structure models respectively (liquid drop model and nuclear sphere packing model), and selected 90 nuclides on the β-stability line and 152 nuclides which have α-decay capability for model analysis. The results show that: For β-stability line analysis, nuclear sphere packing model can better explain the relationship between proton number Z and atomic mass A than liquid drop model, while liquid drop model works better on α decay energy analysis.

Abstract:Reaction of 1,4-bis(imidazol-1-ylmethyl)benzene (bix), 2,6-naphthalenedisulfonic acid (nds) with CdCl2 under hydrothermal condition, yielded a new three-dimensional Cd(II) coordination polymer [Cd(bix)(nds)]n, which was further structurally determined by X-ray single crystal diffraction. The result indicates that the compound exhibits centro-symmetrical in which the cadmium ion is located at the symmetry center. Each Cd(II) ion is six-coordinated with a distorted octahedral coordination geometry. The adjacent Cd(II) ions are connected by bix molecules, giving a one-dimensional chain, and the neighboring chains are further linked by sulfonic ions, resulting in two-dimensional sheet structure. In addition, the sheets are further bridged by the other sulfonic ions, generating infinite 3D network framework architecture.

Abstract:Abstract： Objective: The HPLC method is established for separation and determination of epicatechin, gallic acid, catechin, rutin, myricetin, quercetin and kaempferol in Toona sinensis by ultrasonic extraction. Methods: The separation of seven active ingredients is performed on Phenomenex C18 column (150 mm×4.6 mm, 5 μm) with step gradient. Mobile phase is methanol -0.1% acetic acid at the flow rate of 0.8 mL﹒min-1 ; the UV detection wavelength is 290 nm and the coclumn temperature is set at 35℃. Results: The good separation of epicatechin, gallic acid, catechin, rutin, myricetin, quercetin and kaempferol is achieved within 15 min. Calibration curves of the seven active ingrediens show linear relationship (r>0.9991, n=7). The average recoveries are within 99.23%～104.5% (RSD%<1.26%, n=3). Conclusion: This ultrasonic extraction method is simple, fast, economical and reliable.

Abstract:The Li2TiO3 nanoparticles were prepared by the sol-gel process by employing lithium acetate and tetrabutyl titanate as lithium and titanium sources, respectively, followed by modification with hydrochloric acid to obtain H2TiO3-lithium adsorbent (titanium lithium ionic sieve). Simulation of the saline lake brine was prepared, followed by adding sodium hydroxide to the prepared solution before adsorption to remove Mg2+ as well as Ca2+. Simulative adsorption of Li+ by the obtained adsorbent from the saline lake brine was carried out. The results indicate that the adsorption capacity of H2TiO3-lithium adsorbent for Li+ is 8.25 mg·g-1, and the partition coefficient (Kd) of Li+ is calculated to be 24.54 mL·g-1, which is much larger than that of Na+ (0.52 mL·g-1) and K+ (0.97 mL·g-1). Li+ to Na+ separation factor () is 47.2, and Li+ to K+ separation factor () is 25.3, indicating that the synthesized adsorbent has an excellent selective adsorption performance to Li+

Abstract:The molecule of norfloxacin was investigated with the density functional theory (DFT), and the molecular geometry was optimized by utilizing B3LYP method at the levels of 6-311+G(d,p). Based on the optimized geometry, the infrared absorption spectra (IR) and Raman scattering spectra (Raman), the frontier molecular orbital and the net charge distribution were calculated by the means of quantum mechanics. According to the calculation results of the infrared absorption spectra (IR) and Raman scattering spectra (Raman), characteristic vibrational frequencies of norfloxacin molecule were assigned. Based on the calculation results of the highest occupied orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and the net charge distribution, the characteristics of the highest occupied orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and the potential energy surface were discussed. Based on the molecular geometry was optimized by utilizing B3LYP method at the levels of 6-311+G(2d,p), and applying the theory of GIAO, the nuclear magnetic resonance (NMR) was obtained and the spectral data were analyzed and discussed.

Abstract:Abstract: The molecule of 2,6-dimethyl-4-(2H-pentazol-2-yl)phenol was investigated with the density functional theory (DFT). Through the synthesis route referred in the literature, the reaction mechanism was analyzed by the density functional theory M06L at the level of 6-311g(d,p). Based on the optimized geometry of 2,6- dimethyl- 4- (2H-pentazol-2-yl) phenol, the infrared absorption spectrum (IR), the nuclear magnetic resonance (NMR), and the ultraviolet-visible absorption spectroscopy (UV-Vis) have been obtained with the density functional theory (DFT). According to the calculation results of the reaction mechanism, the character of each step was mainly discussed. The simulated results of the infrared absorption spectrum (IR), the nuclear magnetic resonance (NMR), and the ultraviolet-visible absorption spectroscopy (UV-Vis) were obtained, and the spectral data were concisely analyzed and discussed.

Abstract:In this paper, the phase of electromagnetic field distribution in the cavity is regulated through movements of the metal wall of a rectangular waveguide, which can avoid the inhomogeneous heating caused by the uneven distribution of electromagnetic field in the rectangular waveguide. And the time varying medium method based on space coordinate transformation is proposed to calculate the moving boundary problem, which has a significant effect on solving the moving boundary problem of large industrial microwave cavities. A single mode BJ-22 wave guide heating system is used as the reference in this paper to analyze impacts of short circuit plane position on microwave heating uniformity. Experiments and calculation results show that the uniformity of microwave heating can be greatly improved by regulating of short circuit plane position, and the space coordinate transformation method can be used to calculate the moving boundary of the microwave cavity.

Abstract:This paper investigates the variation of hole concentration with temperature, then discussed the effect of hole concentration , base and temperature on the density of metal - based epitaxial graphene. The results were three fold. First, the hole concentration increases nonlinearly with the temperature increasing, and the rate of change of the hole concentration of the epitaxial graphene with the temperature is smaller than that of graphene. Second, Compared with graphene,When electron energy is zero, the density of states of copper-based epitaxial graphene is higher than that of graphene. Third, the maximum of graphene density decreases at the corresponding electron energy because of the substrate. The density of states of Cu-based epitaxial graphene decreases with the increase of hole concentration and temperature, with the change of the concentration of the hole is linear, but with the temperature change is nonlinear.

Abstract:Two-dimensional molecular dynamics simulations are employed to gain insight on the effect of the different heating mechanism in determining the extent of nonequipartition of kinetic energy in granular gases with a Power-law particle size distribution. It is found that the bulk value of the temperature ratio depends on the choice of different boundary heating.

Abstract:The ABA receptor RCARs play a key role in ABA Signal transduction process, and research on interaction proteins of RCARs has great significance in further understanding the molecular mechanism of plants in adverse environment. The yeast two-hybrid assay and GST-pull down were used to study the interaction between CARK7 and RCAR12. The results showed that there is a significant interaction between CARK7 and RCAR12 in vitro. Then, the bimolecular fluorescence complementation (BiFC) was used to confirm the interaction between CARK7 and RCAR12 in vivo. The BiFC assay indicated that CARK7 was associated with RCAR12 in tobacco epidermal cells. Taken together, these data suggested that CARK7 and RCAR12 closely interact with each other, and illuminating the regulation of the ABA signaling transduction.

Abstract:Abstract: A novel strain of Bacillus pumilus named as SCU11 was screened and mutagenized from the wild strain BA06 in our previous study. The fermentation supernatant of this strain showed efficient dehairing capability, indicating its extracellular proteases has a good application future in leather industry. However, the efficient genetic manipulation system of B. pumilus SCU11 has not yet been established, which greatly hampered the genetic engineering and the basic theory study of this strain. In this study, high osmolarity electroporation method was developed for the efficient transformation of B. pumilus, and the transformation efficiency was obtained up to 3.5×103CFU/μg DNA. Moreover, a temperature sensitive E. coli-Bacillus shuttle vector pUCETs was constructed by making use of a temperature sensitive replication origin, and the peptidase C40 gene of SCU11 was knocked-out based on the pUCETs. The electroporation method and gene manipulation system established in this study could make efficient targeted gene knockout in Bacliius pumilus.

Abstract:To prepare the monoclonal antibody of Canine distemper virus which infect rhrsus monkey, the H gene of the virus was amplified by RT-PCR and cloned into pVAX. The DNA vaccine pVAX-H was injected into Balb/c mice and induced a strong immunity. The spleen cells were fused with SP2/0 cells and 5 hybridoma strains secreting monoclonal antibodies against CDV H gene were achieved. The five different McAbs didn’t react with CPV and MV but could neutralize CDV in vitro. Two of them had high neutralization antibody above 1:256. The result import that the CDV H gene vaccine can be used to prepare monoclonal antibody.

Abstract:Sichuan is one of the three natural distribution centers of Rhododendron in China. To understand the current situation of Sichuan Rhododendron well, the Rhododendron plant specimen database was constructed based on Sichuan University Herbarium (SZ). Statistics and analyses were carried out from different aspects especially on species, collection site, altitude and life-form. The results showed that there were16077 specimens recorded, belonging to 260 species (include 11 subspecies, 29 varieties) in 29 subgroups, 14 groups and 6 subgenus, of which 99 species (include 9 varieties and 3 subspecies) endemic to Sichuan. There were 158 type specimens belonging to 17 species in 6 subgenus. In addition, 16 species of Rhododendron were reported as new record distribution to Sichuan. Rhododendron plants distributed in 75 counties and 15cities (Autonomous Prefecture) of Sichuan, mainly in Liangshan, Gan zi, A ba, Ya an and Le shan, which life type is 1-3 m in height. Six priority species for landscape application in Sichuan were screened by MaxEnt and landscape application value. They are R. lutescens, R. vernicosum, R. pachytrichum, R. concinnum, R. racemosum and R. davidsonianum. These data provide effective information for protective making plans and study work in Rhododendron.

Abstract:Thermal sterilization is widely adopted in peanut protein beverage processing, and may cause Maillard reaction (MR). This paper was designed to research the effect of thermal sterilization induced MR on the subsequent simulated gastrointestinal digestion. Peanut protein isolate (PPI) and glucose (1:1) were heat-treated in 80/100/121 oC for 30 min, then subjected to a simulated gastrointestinal digestion to evaluate the digestion characteristics. PPI without glucose, as a control group, was dealt in the same conditions. Absorbance in 294/420 nm of heat-treated samples and degree of hydrolysis (DH), protein digestibility (PD), molecular weight distribution, free amino acid composition of simulated gastrointestinal digestion products were measured. The experimental results showed that: compared to the control group, PPI heat-treated with glucose caused stronger MR. Heat treatment and MR leaded to an increase of larger molecular weight peptides content. Only heat-treated in 121 oC for 30 min had contributed to the DH increase of simulated gastrointestinal digestion products, and from a general view, MR gone against the digestive and utilizable performance of PPI.

Abstract:This study was focused on a special charophyte collected from Ya'an, Sichuan. Morphological observation showed that it had two-layer coronal, divided branchlets and no cortex. These were the features of Nitelleae. But there was another feature which hadn’t been reported in Nitelleae, papillary stipulodes, at the base of node and beneath the branchlets. The identical stipulodes were observed no matter in the fresh collected samples or in the laboratory cultured specimens or in the seedlings coming from the germinated oospores in the laboratory. Long time observation indicated that the stipulodes feature was stably inherited in this special charophyte. Further molecular phylogenetic analyses, which combined the 18s rDNA gene with the rbcL gene, demonstrated that new feature charophyte clustered with other species of Nitella as a single clade. Combining the morphological observation with the molecular analyses illustrated the new feature charophyte belonged to Nitella. Our research demonstrated that not only the Chareae but also the Nitelleae had stipulode. And the new feature charophyte was an important supplement to Nitella. New feature charophyte provided an evidence for the revision of the classification system of charophytes.

Abstract:Most recently a new group of regioselective adenine halogenases AcmX and AcmY have been found in Streptomyces, which can be employed to develop the halide substitution of nucleoside-like drugs. The crystal structures of this new family of halogenase are the basis to elucidate the catalytic mechanism and biosynthesize nucleoside-like drugs with halogen modifications. In order to solve the structure of AcmX of this new halogenase family, AcmX was overexpressed in Escherichia coli but was initially as the inactive inclusion body. Thus we constructed a dual expression system for AcmX and the chaperone plasmid pGro7, which promotes AcmX to fold properly by controlling the expression level of the chaperone plasmid. The chaperone protein is inclined to co-purify with the target protein but can be removed by a step of gel filtration chromatography, so that the protocol can be established to obtain AcmX in high quality, leading to the successful crystallization. This study will facilitate X-ray diffraction data collection and structure determination for AcmX and provide a useful protocol for the other difficult cases in expression and purification.

Abstract:AHA2 anchors within the cytoplasm membrane of plant cell. In prokaryotic expression system, the protein can’t be recombinant expressed. In Saccharomyces cerevisiae expression system, the procedures of AHA2 purification stay complex and expensive. By means of RT-PCR and molecular cloning, we constructed an eukaryotic expression vector of AHA2 with PiChia as host. By method of affinity chromatography and gel filtration chromatography, we obtained target protein in highly active with high quality.

Abstract:Strigolactones(SLs) constitute the recently discovered group of plant hormones, they participate in inhibiting shoot branching and promoting parasitic and symbiotic interactions in the rhizosphere. Three SLs-related genes were obtained from Brassica napus by homologous cloning, named BnMAX4, BnMAX1, BnD14; the length of CDS was 1707, 1593, 804 bp; encoding 568, 530, 267 amino acids; the putative protein function was β-carotenoid oxygenase, cytochrome P450, α/β hydrolase, respectively. Using roots, stems and leaves of wild type B. napus at two-euphylla one-bud and four-euphylla one-bud stage, expression of the three genes was analyzed by RT-qPCR, the results showed that BnMAX4 mainly expressed in the roots at two-euphylla stage; BnMAX1 didn’t show expression advantage; BnD14 significantly expressed in leaves at two-euphylla stage. Then expression of the three genes was analyzed under the drought and salt stress, the expression of BnMAX4 suddenly decreased under both stress conditions. The expression of BnMAX1 decreased under drought stress; under salt stress the expression decreased first and increased afterwards, after 9Hr decreased again. The expression of BnD14 showed two high peaks at 3Hr and 12Hr under drought stress; under salt stess the expression showed one high peak at 3Hr. Those studies have shown that the expression of BnMAX4 and BnD14 had certain tissue-specificity, and the three SLs-related genes involved in drought and salt stress responses of B. napus.