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We present an efficient three-dimensional (3D) time-domain airborne electromagnetic (EM) modeling based on finite-volume method, in combination with the merits of solving the secondary field, local mesh, and the direct solver. Taking the strategy of separating primary from secondary field for the calculation of time-domain EM field, we greatly reduce the number of grids in comparison to direct solution of the total field. The primary field is obtained by Hankel transform from the frequency-domain for a half-space or layered earth model. The techniques of local mesh and direct solver are adopted to further improve the modeling efficiency. We compare and discuss the characteristics of the method developed in this paper from time consumption and grid sizes. The EM responses for different transmitting waveforms are calculated via a convolution between step-wave responses and the transmitting current or its derivatives. All numerical experiments on models with multiple geological bodies and fracture zones have demonstrated that our modeling algorithm is efficient and effective when simulating AEM system responses. [ABSTRACT FROM AUTHOR]

The thermal behavior of blends of nylon 6 (PA6, nylon 6)/acrylate rubber which were obtained by melt processing have been investigated by differential scanning calorimetry. The differential scanning calorimetry result indicates that the melting temperature and the crystallization temperature of blends decrease lightly with the increase of acrylate rubber content in the blends. The crystallization behavior of the blends studied by wide angle X-ray diffraction reveals that a γ→α crystal transformation occurs upon adding acrylate rubber into nylon 6. Furthermore, the crystallinity and crystal size decrease with adding acrylate rubber into nylon 6. The crystal morphology of nylon 6 and nylon 6/acrylate rubber blends was observed by the polarizing microscope. It is found that the crystal size of nylon 6/acrylate rubber gradually becomes smaller and crystal morphology of nylon6 / acrylate rubber gradually becomes imperfect with the increase of acrylate rubber content in the blends. [ABSTRACT FROM PUBLISHER]

HrpNEa is a harpin protein from Erwinia amylovora, a bacterial pathogen that causes fire blight in rosaceous plants. Treating plants with HrpNEa stimulates ethylene and abscisic acid (ABA) to induce plant growth and drought tolerance, respectively. Herein, we report that both growth hormones cooperate to mediate the role of HrpNEa in promoting root growth of Arabidopsis thaliana seedlings. Root growth is promoted coordinately with elevation in levels of ABA and ethylene subsequent to soaking of germinating seeds of wild-type (WT) Arabidopsis in a solution of HrpNEa. However, these responses are arrested by inhibiting WT roots from synthesizing ethylene as well as sensing of ABA and ethylene. The effects of HrpNEa on roots are also nullified in ethylene-insensitive etr1- 1 and ein5- 1 mutants and in the ABA-insensitive mutant abi2- 1 of Arabidopsis. These results provide evidence for presence of a relationship between root growth enhancement and signaling by ABA and ethylene in response to HrpNEa. Nevertheless, when HrpNEa is applied to leaves, ethylene signaling is active in the absence of ABA signaling to promote plant growth. This suggests the presence of a different signaling mechanism in leaves from that in roots. [ABSTRACT FROM AUTHOR]

[Objective] This study aimed to construct RNAi expression vector against riboflavin synthase (RS) gene. [Method] By using the primers designed based on RS gene coding sequence that was screened from Arabidopsis cDNA library, the 476 bp cDNA fragment of RS was amplified from pGADT7-RS recombinant plasmid, and then cloned into pUCm-T vector to obtain pUCm-RS. Two RS fragments (476 bp) were obtained through digesting pUCm-RS with restriction enzymes PstI/BamHI and PstI/XhoI, and then respectively connected into vector pBSSK-in to form pBSSK-RS-in-RS, in which the two RS fragments were inverted repeats. Finally, the transform unit RS-intron-RS, got by digesting vector pBSSK-RS-in-RS with Sac I and Kpn I, was ligated into expression vector pCAMBIA1301 to obtain the RS gene silencing vector. [Result] The restriction enzyme digestion sequencing analysis proved that the RS gene silencing vector was successfully constructed. [Conclusion] This study may provide a basic: material for further studies on the bio-function of RS gene and the mechanism of signal transduction induced by HpaGXoo in plant. [ABSTRACT FROM AUTHOR]

Harpins of phytopathogenic bacteria stimulate defense and plant growth in many types of plants, conferring disease resistance and enhanced yield. In a previous study, we characterized nine fragments of the harpin protein HpaGXooc from Xanthomonas oryzae pv. oryzicola for plant defense elicitation and plant growth stimulation activity relative to the intact protein. In plants grown under controlled conditions, the fragment HpaG10-42 was more active in both regards than HpaGXooc. Here, we demonstrate that the activity of HpaG10-42 in rice under field conditions significantly exceeds that of HpaGXooc, stimulating resistance to three important diseases and increasing grain yield. We carried out tests in 672 experimental plots with nine cultivars of rice planted at three locations. Application protocols were optimized by testing variations in application rate, frequency, and timing with respect to rice growth stage. Of the concentrations (24, 24, 12, and 6 μg/ml), and number and timing of applications (at one to four different stages of growth) tested, HpaG10-42 at 6 μg/ml applied to plants once at nursery seedling stage and three times in the field was most effective. Bacterial blight, rice blast, and sheath blight were reduced 61.6 and 56.4, 93.6 and 76.0, and 93.2 and 55.0% in indica and japonica cultivars, respectively, relative to controls. Grain yields were 22 to 27% greater. These results are similar to results obtained with typical local management practices, including use of chemicals, to decrease disease seventies and increase yield in rice. Our results demonstrate that the HpaG10-42 protein fragment can be used effectively to control diseases and increase yield of this staple food crop. [ABSTRACT FROM AUTHOR]