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Myeloblastosis (MYB) transcription factors are one of the largest families of transcription factors in higher plants. They play an important role in plant development, defense response processes, and non-biological stresses, i.e., drought stress. Foxtail millet (Setaria italica L.), originated in China, is resistant to drought and low nutrition stresses and has been regarded as an ideal material for studying abiotic stress resistance in monocotyledon. In this study, we ran a transcription profile analysis of zheng 204 under low-nitrogen conditions and identified a MYB-like transcription factor SiMYB42, which was up-regulated under low-nitrogen stress. Phylogenetic tree analysis showed that SiMYB42 belongs to R2R3-MYB subfamily and has two MYB conserved domains. Expression pattern analysis showed that SiMYB42 was significantly up-regulated under various stress conditions, including low-nitrogen stress, high salt, drought and ABA conditions. The results of subcellular localization, quantitative real-time PCR and transcriptional activation analysis indicated that SiMYB42 protein localizes to the nucleus and cell membrane of plant cells, mainly expressed in the leaf or root of foxtail millet, and has transcription activation activity. Functional analysis showed that there was no significant difference between transgenic SiMYB42 Arabidopsis and wild-type (WT) Arabidopsis under normal conditions; however, under low-nitrogen condition, the root length, surface area and seedling fresh weight in transgenic SiMYB42 Arabidopsis, were significantly higher than their counterparts in WT. These results suggest that SiMYB42 transgenic plants exhibit higher tolerance to low-nitrogen stress. Expression levels of nitrate transporters genes NRT2.1, NRT2.4 and NRT2.5, which are the transcriptional targets of SiMYB42, were higher in transgenic SiMYB42 Arabidopsis plants than those in WT; the promoter regions of NRT2.1, NRT2.4 and NRT2.5 all have MYB binding sites. These results indicate that SiMYB42 might enhance foxtail millet tolerance to low-nitrogen condition through regulating the expression of nitrate transporter genes. This study reveals the possible functions of SiMYB42 in a low-nitrogen stress response pathway, and provides a foundation for further understanding the entire regulation network of foxtail millet in response to low-nitrogen stress.

The pile-soil interaction under wave loads is an extremely complex and difficult issue in engineering. In this study, a physical model test is designed based on the principle of the gravity similarity to obtain time histories of wave forces of unsteady regular waves, and to measure the magnitude and the distribution of wave forces acting on the piles. A numerical model and relevant numerical methods for the pile-soil contact surface are adopted based on the principles of elastic dynamics. For a practical project, the time histories of wave forces on the piles are obtained through physical model tests. The deformations of the piles in the pile-soil interactions and the distribution of the bending moment on the piles are studied. It is shown that, with the increase of the period of wave pressures, the absolute value of the horizontal displacement of the piles increases, the embedment depth of the piles increases, and the scope of influence of soils increases. The change of the bending moment on the piles is consistent with that of its theoretical results, and the proposed numerical method can very well simulate the properties of the piles.

Mechanical parameter analysis is a complicated issue since it is influenced by many factors. Closely related with the influencing factors of compressibility coefficients of rock material (sandstone), this article first introduces the way to process partial least square regression (PLSR) analysis. The process of carrying out PLSR is divided into six steps as for analysis and prediction of the regression model, which are data preparation, principle collection, regression model for first principle component, secondary principle analysis, establishment of final regression model and number determination of principal component l. And then introduces PLSR for application of analysis and prediction of compressibility coefficients with 30 experiment samples. Seven prediction samples are carried out by PLSR with the training process of 30 samples. The result shows PLSR has good accuracy in prediction under the condition that the model is properly deprived based on certain experimental samples. Finally, some conclusions are made for further study on both mechanical parameters and partial least square regression method.

On 28 October 1996, a landslide occurred on the Huashiban slope near the Liangjiaren Hydropower Station. The landslide was caused by a failure mechanism induced by an earthquake (Mw 7.0) at Lijiang on 3 February 1996, after which a tensile fracture zone formed on the Huashiban slope. The subsequent impact of several small earthquakes on the slope increased the tension crack connectivity and the tensile strength gradually decreased. Severe rainfall in the rainy season between May and October, especially in July and August, decreased the shear strength of the bottom sliding surface, resulting in a landslide on the Huashiban slope on 28 October 1996. The stability of the Huashiban slope is important for plant site selection. If a further landslide occurs on the slope, the Liangjiaren Hydropower Station project will be critically affected, so analysis of the current slope stability is extremely important. At present, the Huashiban slope can be divided into five subzones: (1) a landslide deposit zone; (2) a landslide zone; (3) a tensile fracture zone; (4) a crescent-shaped zone; and (5) an upper slide zone. Using historic landslide data for 28 October 1996, retrospective analysis of the landslide process revealed shear strength parameters for the Huashiban slope. The cohesion strength is 0.024 MPa, the friction angle at the bottom sliding surface is 14°, and the tension crack connectivity is 50%. These parameters were used to compute the stability of the Huashiban slope. Under the same conditions, the stability of the whole slope is better than that of part of the slope, and the overall stability is dominated by the tensile fracture zone. Under earthquake and rainfall conditions, it is possible that failure will occur in the tensile fracture zone. Thus, the Huashiban slope should be reinforced for construction and operation of the Liangjiaren Hydropower Station.

Based on the background of Goupitan Hydropower Project high slope to research saturated-unsaturated seepage problems under atomized rain. Firstly, influence factor of flood discharge atomization is analyzed, the rainfall intensity and distribution of flood discharge atomization is researched by fuzzy mathematics, using the measured data, and a membership function of flood discharge atomization is built on the basis of statistical analysis and expertise, and then forecast the rainfall intensity and range by the fuzzy comprehensive judge. Secondly, According to the control equation of saturated-unsaturated state, the integral saturated-unsaturated unsteady seepage control equation is constituted on the connection of saturation degree. The FEM computation format of mathematic model is deduced by Galerkin weighing margin method, the compute iterate mode of nonlinear FEM is developed, and the three dimensional FEM program of computing saturated-unsaturated unsteady seepage under ground seepage condition by FORTRAN language, the solving technical methods and convergence speed are improved. At last, based on the slope geological characteristics, the slope geological model and calculation model are building, the saturated-unsaturated seepage field under ground seepage condition for the high rocky slope is simulated, and the result could provide important scientific references for seepage control measures and safety estimate in Hydropower Project.

The interaction between Cu2+, Fe3+ and Melanin from Taihe Silky fowl for different pH values was investigated in heterogeneous system.The IR spectrum of melanin and its complexes with Cu2+, Fe3+ ions was determined.The carbonyl group of melanin may interact with metals.Taihe Silky fowl melanin is the mixture of pheomelanin and isomelanin.