Guan Q.,University of Maryland University College |
Lu X.,Xinjiang Agricultural University |
Zeng H.,University of Maryland University College |
Zhang Y.,University of Maryland University College |
Zhu J.,University of Maryland University College
Plant Journal | Year: 2013
Summary microRNAs (miRNAs) play important roles in plant growth and development. Previous studies have shown that down-regulation of miR398 in response to oxidative stress permits up-regulation of one of its target genes, CSD2 (copper/zinc superoxide dismutase), and thereby helps plants to cope with oxidative stress. We report here that heat stress rapidly induces miR398 and reduces transcripts of its target genes CSD1, CSD2 and CCS (a gene encoding a copper chaperone for both CSD1 and CSD2). Transgenic plants expressing miR398-resistant forms of CSD1, CSD2 and CCS under the control of their native promoters are more sensitive to heat stress (as indicated by increased damage at the whole-plant level and to flowers) than transgenic plants expressing normal coding sequences of CSD1, CSD2 or CCS under the control of their native promoters. In contrast, csd1, csd2 and ccs mutant plants are more heat-tolerant (as indicated by less damage to flowers) than the wild-type. Expression of genes encoding heat stress transcription factors (HSF genes) and heat shock proteins (HSP genes) is reduced in heat-sensitive transgenic plants expressing miR398-resistant forms of CSD1, CSD2 or CCS but is enhanced in the heat-tolerant csd1, csd2 and ccs plants. Chromatin immunoprecipitation assays revealed that HSFA1b and HSFA7b are the two HSFs responsible for heat induction of miR398. Together, our results suggest that plants use a previously unrecognized strategy to achieve thermotolerance, especially for the protection of reproductive tissues. This strategy involves the down-regulation of CSD genes and their copper chaperone CCS through heat-inducible miR398. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.
Mamut J.,Xinjiang Agricultural University |
Xiong Y.-Z.,Wuhan University |
Tan D.-Y.,Xinjiang Agricultural University |
Huang S.-Q.,Wuhan University
New Phytologist | Year: 2014
Gynomonoecy, a sexual system in which plants have both pistillate (female) flowers and perfect (hermaphroditic) flowers, occurs in at least 15 families, but the differential reproductive strategies of the two flower morphs within one individual remain unclear. Racemes of Eremurus anisopterus (Xanthorrhoeaceae) have basal pistillate and distal perfect flowers. To compare sex allocation and reproductive success between the two flower morphs, we measured floral traits, pollinator preferences, and pollen movement in the field. Pollen limitation was more severe in pistillate flowers; bee pollinators preferred to visit perfect flowers, which were also capable of partial self-fertilization. Pollen-staining experiments indicated that perfect flowers received a higher proportion of intra-plant pollen (geitonogamy) than pistillate flowers. Plants with greater numbers of pistillate flowers received more outcross pollen. The differential reproductive success conformed with differential floral sex allocation, in which pistillate flowers produce fewer but larger ovules, resulting in outcrossed seeds. Our flower manipulations in these nectarless gynomonoecious plants demonstrated that perfect flowers promote seed quantity in that they are more attractive to pollinators, while pistillate flowers compensate for the loss of male function through better seed quality. These results are consistent with the outcrossing-benefit hypothesis for gynomonoecy. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.
Zhu X.-L.,Xinjiang Agricultural University
Chang'an Daxue Xuebao (Ziran Kexue Ban)/Journal of Chang'an University (Natural Science Edition) | Year: 2010
Considering the uncertainty of highway geometry design parameters, the reliability models involved in stop sight distance (SSD), horizontal curve radius (HCR) and vertical curve radius (VCR) are developed based on probability theory. Reliability indexes and failure probability are obtained by reliability calculation method and are used to analyze reliability of highway alignment design indicators. The study results show that the reduction of stop sight distance (SSD) should be limited in the range of 15 percent at any point in highway to guarantee the reliability of SSD. The declination of lateral friction factors significantly affects the reliability of HCR. If the reduction of VCR exceeds a certain value, the VCR reliability will sharply decline. Reliability theory in highway alignment design provide theoretical basis for the designers who are confused about the best choice between safety and cost for any factor. Meanwhile, it offers the designers a new design idea.
Zhu X.,Xinjiang Agricultural University
ICCMS 2010 - 2010 International Conference on Computer Modeling and Simulation | Year: 2010
An accurate mathematical model for describing traffic accidents is difficult to be constructed due to various factors such as humans, vehicles and environments. To achieve a better estimation of traffic crashes, a novel composite grey BP neural network(CGBNN) model is presented in this paper. First, the original predicted values of traffic accidents are separately obtained by the GM(1,1) model, the Verhulst model and the DGM(2,1) model. Then, a CGBNN model is constructed by fusing the advantages of the grey models and the BNN model to improve the forecasting precision of the original grey models, the reasonable weights of the neural networks are acquired by an iterative training and learning process. The results of the CGBNN model on predicting real-world traffic fatalities show that the forecasting accuracy is much enhanced when the proposed method is applied. © 2010 IEEE.
Su Y.,Xinjiang Agricultural University
Wei sheng wu xue bao = Acta microbiologica Sinica | Year: 2012
In order to compare the infection of HIV-1 pseudovirus to suspended and adherent cells, Tzmbl cells containing beta-gal (beta-galactosidase) reporter gene were used here to do the analysis. pseudoviruses were generated by co-transfection of 293T cells with the plasmid pNL43R-E- and HIV envelope expressing plasmid. Supernatant of co-transfected 293T cells was collected and used to infect Tzmbl cells with or without trypsin treatment. Forty-eight hours after infection, beta-gal positive Tzmbl cells and virus infection were determined using X-gal staining and beta-glo (beta-galactosidase) assay. The efficiency of HIV pseudoviruses infection of suspended Tzmbl cell was higher than that of adherent cells and the increase of infection correlated with the pseudoviral subtype. This study may provide a useful method for HIV biological study and neutralization assays using a single-round replicative pseudovirus in the future.
Zhang X.,Xinjiang Agricultural University
Wei sheng wu xue bao = Acta microbiologica Sinica | Year: 2010
OBJECTIVE: To study endophyte species of Achnatherum inebrians and to screen strains with insecticidal activity against cotton insect. METHODS: We isolated endophytic from roots,stems,leaves and seeds of health A. inebrians by grinding separation method and identified by a dual approach of morphological and physiological observation and 16S rDNA gene (for bacteria) and ITS sequence (for fungi) based molecular identification. Then,those endophytes were inoculated into liquid media for fermentation and the crude extracts were used to test insecticidal activities by slide disc immersion and nebulization methods. RESULTS: We isolated bacteria species classified into 8 genera of Bacillus, Streptomyces, Corynebacterium, Phyllobacterium, sphingomonnas, Paenibacillus, Pseudomonas, Acinetobacter and 2 fungi of Claviceps purpure and Claviceps Chaetomium. Of them, the strain Streptomyces rochei (GA) and Claviceps purpurea (PF-2) had more than 85% of mortality to cotton aphis. CONCLUSION: Two strains of PF-2 and GA associated within the A. inebrians had significant insecticidal activity to cotton aphis (Aphis gossypii), which may provide a new biological resource to explore new microbial insecticide.
Zhao J.,Xinjiang Agricultural University
Proceedings - 2016 8th International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2016 | Year: 2016
English for science and technology(EST) is an important way to describe scientific work, and flexible means(FM) is the generally accepted method to translate EST. In this paper, we evaluate the application of flexible means in EST translation(ESTT) via the explicit questionnaire. Directly employing the principal component analysis(PCA), we obtain the relative importance of seven different kinds of FM. Based on analytic hierarchy process(AHP), we take three kinds of EST including biological EST(BEST), agricultural EST(AEST) and medical EST(MEST) as our objects to investigate the application of FM, with the seven FM being criterion layer and the three EST being scheme layer. We find that, the application of FM in BEST is the most common among the three EST. © 2016 IEEE.
Mu Z.,Xinjiang Agricultural University |
Zhang Z.,China Institute of Water Resources and Hydropower Research |
Zhao T.,Xinjiang Agricultural University
Procedia Engineering | Year: 2012
The desired outcome of flow characteristics from the model testing on spillway design process often can not be measured on the specific situation, but it is possible to obtain much of this information through numerical modeling. The flow characteristics in a whole spillway has been simulated based on the VOF method multidimensional two-phase flow model and standard k∼ε method by FLUNT software under the conditions of the checked flood level (650.39m) and the design flood level (653.36m). The numerical computation results of the surface elevation, pressure and flow velocity along the spillway in two schemes fit the experimental results well, and the difference of the average velocity between calculated and experiment results was less 6%. By model tests and numerical simulation, it found that the flow pattern and surface elevation of two holes scheme is complex caused by boundary conditions, but it is well after modifying to single hole. So the advanced CFD method is used to solve the design problems in a practical spillway design, and the calculation results can be used as the basis of the shape optimization. © 2012 Published by Elsevier Ltd.
Zhang L.,Xinjiang Agricultural University
Paiguan Jixie Gongcheng Xuebao/Journal of Drainage and Irrigation Machinery Engineering | Year: 2016
The dynamic deformation properties of saturated gravel soil were studied under a dynamic loading by using tri-axial test in laboratory. The effort was mainly focused on the influence of vibration frequency, consolidation pressure and consolidation stress ratio on the dynamic constitutive relation and dynamic modulus of elasticity. It is indicated that the dynamic stress-strain curve is of hyperbolic type, and approaches gradually towards the stress axis direction with the increasing of consolidation pressure and consolidation stress ratio, but the vibration frequency has a less effect on the stress-strain curve of the gravel soil. The dynamic elastic modulus decreases with the increasing of dynamic strain, but remains nearly unchanged at last. The vibration frequency affects the curves less because the experimental data are generally in the same zone; the consolidation pressure and consolidation stress ratio, however, demonstrate a great influence on the curves. The Ed/Ed max-εd curves under different vibration frequencies and consolidation pressures have a relatively good normalization property, while those under various consolidation stress ratios do not. © 2016, Editorial Department of Journal of Drainage and Irrigation Machinery Engineering. All right reserved.
Liang L.,Xinjiang Agricultural University
Electronic Journal of Geotechnical Engineering | Year: 2015
Taking a subway station deep foundation pit engineering in Qingdao as the background, monitoring analysis supporting structure, strut axial forces, underground water etc, and compared MIDAS simulated analysis with field monitoring data. Deformation law are set out below: (1) monitoring and simulation data is relatively close to both law of retaining pile top displacement of foundation pit support as the increases with the increasing of the number of; To pit retaining pile body displacement as the depth of pile depth increasing and decreasing; (2) the steel support has played a very good supporting effect, effectively prevent the retaining piles as a whole appear larger deformation rate; In supporting axial force changing with time have been gradually growing trend; (3) the steel support with support and the increase of excavation depth, the rear axle force increase rapidly for a period of time, basically stable unchanged within a certain range. Research results of significance of reference to the similar design and construction of foundation pit engineering. © 2014 ejge.