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- Abstract：A variety of Marek's disease virus (MDV) lymphoblastoid cell lines have been established. The MDV lymphoblstoid cell line, MDCC-MB1(MSB1) were treated with 5-azacytidine (5-AZC) and resulted in demethylation of MDV DNA and the increase in mRNA from certain portions of the MDV DNA When MDV DNA was digested with DnaseI, new bands appeared and the increases in mRNA from these portions of the MDV DNA were detected by using southern and northern blotting hybridization. These results suggest MDV DNA transcriptional activity was increased by demethylation, and the methylation of MDV DNA appears to be one of the factors associated with the repression of thanscription of MDV DNA in the lymphoblastoid cell line, MSB1.Keywords：lymphoblastoid cell,MDV DNA,demethylation,mRNA sythesis,5-AZC0|7|0<HTML><L-PDF> <Meta-XML>Updated：2023-12-22
- Abstract：Twenty high oil corn(HOC) inbred lines and five normal corn(NOC) in bred lines from different germplasms were used to make NCII crosses to analyze oil xenia effects and segregation of F 2 kernels. Results showed that dominant high oil gene might exist in high oil line N1680 based on its significant oil xenia effect and F 2 oil concentrations near to the high oil line. Besides, oil concentration distribution analysis showed that transgressive segregations were also obvious in the F 2 kernels, which confirmed further that the gene had interaction with others.Keywords：maize,high oil dominant gene,gene interaction,xenia,transgressive segregation3|2|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：The seed development of the Elymus sibiricus L. was of character in typical graminaceous plants. The embryogeny developed to Gramineous type. Endosperm was of nuclear type.Its outer layer cells developed to aleurone layer. Seed coat was developed from both inner integument and the inner epidermis of ovary. However, it had its own characters. The zygote was round-shaped, appeared no polarity and filled with starch grains. The first division was transverse, occasionally oblique, and then produced apical and basal cells. The vertical division of the apical and the transverse division of the basal formed 4-cells proembryo. The persistent synergid existed during ellipsoidal embryo formation, and had a strong PAS reaction which was similar as filiform apparatus. The embryo development was found retarded in some seeds. The number of starch grain was different among the early proembryos. About 1% of the matured seeds did not contain embryos.Keywords：Elymus sibiricus L.,seed,development,anatomical observation0|6|0<HTML><L-PDF> <Meta-XML>Updated：2023-12-22
- Keywords：DNDC model,soil organic carbon,fertilize,tillage3|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：The plant climatic production potential (PCPP) of Beijing mountain area separated into 1?km2 grids was calculated with Miami and Thornthwaite-Memorial model using climatic data. The PCPP data were finally transferred to visual images with a software of ArcGis and ArcView. The results showed that the PCPP decreased form east to west. The northeast parts of southern Miyun and middle Pinggu had a highest PCPP, but the lowest PCPP was found the west of Mentougou County, the north of Huairou County and the most part of Yanqing County, where both the temperature and precipitation were low. Except the high altitude area, water condition was the main limited factor of the PCPP in this region.The conclusion was confirmed by the results of the analysis with the Miami model. The water deficit was at the range of 130-260?mm. The result of the PCPP was validated by the method of remote sensing. The relationship between the PCPP and NDVI was significant at to 0.01 level.The estimated results of Thornthwaite-Memorial model was better than the Miami model.Keywords：grid,geographic information system (GIS),plant climatic production potential,restricting factor,NDVI3|2|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：To convert the resistance from the simulated unit of the tractor-implement combination to tractor working load, a simulated unit of tractor working load is designed. It was composed of the power transmission output, universal joint and propeller shaft, acceleration gearbox and electric eddycurrent dynamometer, simulated plough and hydraulic loading device. The experiment results showed that change trend both traction produced by resistance of the simulated loading system and brake torque produced by the electric eddycurrent dynamometer were same as jump signal of plough depth. The measured value changes with setting value of braking torque. This device could realize real-time simulation of tractor working load and take many loading studies on implement units.Keywords：tractor,working load,simulation2|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：The paper introduces a linear model of no-tilling seeding movement, in order to dessribe the relation of the movement character of no-tilling seeding to sowing quality. Analyses of the 1205NT no-tiller with MATLAB showed that with in creasing working speed of no-tilling seeding, the resonance amplitude increases from -27?dB to -14.8?dB, and resonance frequency enhances from 14.6?Hz to 23.3?Hz. Vibration affects seed depth in the course of seeding and restricts sowing performance of no-tilling seeding. A conclusion is drawn that the model is suitable, because it can truly reflect the movement of no-tilling seeding.Keywords：no-till seeding,movement character,linear-mode,MATLAB0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：upland rice,mtlD gene,salt-tolerance,microprojectile bombardments1|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：greenhouse,natural ventilation,computational fluid dynamics,numerical simulation2|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：Diospyros kaki,pigment,carotenoids,stability1|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：As a traditional PC or SCM system had the features of a strict working condition, a skill manipulator, and poor reliability, we adopted a PLC as a controller in an automatic grafting machine. The overall design of an automatic grafting machine, the design of a PLC control system, as well as the programming realizations of the driving and executing devices were introduced in this paper. The experimental results from a sample machine showed that the engrafting rate of the automatic grafting machine base on PLC reached 1?200 to 1?380 plants per hour. Compared with a traditional grafting machine, the work efficiency was increased by 100%.Keywords：automatic grafting machine,PLC,control system1|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：To realize the ventilator speed adjustment of a piglet house a control method by zero-crossing power adjustment of Silicon Controlled Rectifier (SCR) was developed based on the investigations and analyses of a motor speed control process. By means of a zero-crossing burst mode, the SCR exports complete sinusoidal wave voltage, which has no high-order harmonic produced, no influences on the voltage of power network, and no interferences on the communication apparatus. The hardware design of the system is simple and the apparatus are easy for overhauling and maintaining for its zero-crossing bursting and the main loop of the SCR are completed by a cooperative operation of the hardware and the software and the software plays a key role in the control process.Keywords：speed control,SCR,zero-crossing power adjustment3|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：An embedded image processing system based on TMS320C6711, as well as its software system, was adopted to realize the transplantation of the tissue culture plantlet recognition algorithm on the system, which satisfied the needs of an image processor with high speed and small size used for a tissue culture plantlet robot. The crucial problems, such as programming bootloader, interrupt vector, command file, and assigning memory space, optimizing code and achieving mix-language programming, were discussed aiming at the characteristics of the embedded system during the software development. The system has a good stability, strong real-time capability, and high accuracy.Keywords：recognition algorithm,DSP,TMS320C6711,software exploitation,transplantation2|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：flaxseed,oven heating,solvent extracting,microwave roasting,water boiling,HCN0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：stress intensity factor (SIF),cylindrical shell structure,crack,Bulging deformation,1|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：A theoretical method for height determination of a reinforced concrete bream (RCB) was developed in this paper, which could be used in the scheme design stage by a structure engineer. Based on the concept to build the deflection curve equation of a normal beam, the maximum beam span depth ratio of a RCB was derived by considering the creep, optional steel ratio of reinforced concrete, deflection and load-carrying capacity criterions. After the analyses of the parameters from a RCB at various typical loading conditions, the following data were suggested: the span/depth ratio was between 8 to 12 for a simply supported primary beam; 12 to 20 for a simply supported secondary beam; and 1.5 times of a simply supported beam for a fixed beam in engineering design. The height determination of a RCB can be made by the theoretical method present here, but not only by the experience method as usual. The result from this method is completely agreed with that from the experience method.Keywords：reinforced concrete beam,beam span depth ratio,deflection0|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Keywords：near infrared spectra,PLS regression model,temperature calibration1|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：The meshless method based on radial basis functions was adopted to solve the differential equations. The properties of the two radial basis functions were investigated and the relational curves of the solution precision and the free parameters in the radial basis functions were obtained. The formula for the optimum value of the free parameter and its calculated value when the nodes were uniformly distributed were also obtained from the solution. We applied that formula to the condition of random nodes and found its solution could still keep a satisfied precision. We compared the computation precisions of the solutions under the conditions of various nodes distributions and the results showed that the precisions didn't change obviously, which meant that this method wasn't sensitive to the distribution of nodes.2|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
- Abstract：Given a set of scattered three-dimensional points, we propsed the Successive Over Relaxation Method(SOR) for surface fitting and smoothing scattered data. The problem was actually the minimum one of quadratic functionalizing about surface smoothness. Nine-point difference schemes of surface functional values at parameter gridding points were obtained according to optimal condition. We treated the constraints with penalty function method after quadratic functional being discrete. The property of symmetric and positive coefficient matrix of linear equations was proved. Then the SOR method converged for any choice of initial vector. The method can be used in the field where smoothing shape is desired by interpolating or approximating a given scattered point set. Numerical examples from simulated and real data were presented to show the efficiency of the new method.Keywords：smoothing,penalty function,difference scheme,iteration methods were investigated and the relational curves of the solution precision and the free parameters in the radial basis functions were obtained. The formula for the optimum value of t1|1|0<HTML><DownloadPDF> <Meta-XML>Updated：2023-12-22
