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The loss of N in farmland is an important cause of agricultural non-point source pollution, which seriously impacts the aquatic environment. A two-year (2017–2018) experiment was conducted to investigate the characteristics of runoff and N losses under different tillage practices. Taking downslope ridge planting and cross ridge planting as the experimental treatments, the characteristics of surface runoff, interflow, and N losses in sloping farmlands with yellow soil were studied throughout the maize growth period. As the rainfall increased, the surface runoff and interflow also increased. The surface runoff and N losses in the surface runoff of downslope ridge planting were significantly higher than those of cross ridge planting. The interflow volumes and N losses in the 0–20 and 20–40 cm soil layers of the cross ridge planting were significantly higher than those of the downslope ridge planting. The total N (TN) losses from surface runoff accounted for 54.95–81.25% of the N losses from all pathways. Therefore, we inferred that surface runoff is the main pathway of N losses. Dissolved total N (DTN) was the main form of N loss under different tillage measures, as it accounted for 55.82–94.41% of the TN losses, and dissolved organic N accounted for 52.81–87.06% of the DTN losses. Thus, we inferred that dissolved N is the main form of N loss. Future research must focus on the prevention and control of the N losses during the maize seedling stage to reduce the environmental pollution caused by ammonium N through runoff.

In this paper, a class of new extended shift-splitting (NESS) preconditioners containing t > 0 are proposed for saddle point problems, which contain the existing shift-splitting-based preconditioners as special cases. The convergence properties of the NESS iteration and the spectral distribution of the NESS preconditioned matrix are investigated. We give an estimated bound for the real eigenvalues of the NESS preconditioned matrix whose left end is positive and show that the non-real eigenvalues of the NESS preconditioned matrix are located in an intersection of two rings, particularly, these non-real eigenvalues are located in an intersection of two rings and one circle if t ≥ 1 2 . Moreover, we show that under appropriate conditions our proposed eigenvalue bounds are tighter than the corresponding bounds given in Ren et al. (2017). Using Fourier analysis, we derive an optimized parameter t ∗ independent of the viscosity ν for the continuous version of the NESS preconditioned GMRES method for the 2D Stokes equation. Moreover, we find that the NESS preconditioned GMRES method with a constant multiple of the optimized parameter t ∗ is effective and robust to solve 2D Stokes problems in practice. Numerical experiments are used to verify our theoretical results.

In this paper, we first propose three kinds of variants of the Uzawa method for solving three-order block saddle point problem and study the convergence conditions of the proposed methods. Second, we obtain the approximate optimal relaxation factors of the three proposed Uzawa type methods by using variable control method. Finally, the experimental results show that our proposed Uzawa type methods for solving three-order block saddle point problem have less workload per iteration step than the corresponding Uzawa type methods for solving standard saddle point problem, which explains that our proposed methods are feasible and efficient.

We demonstrate a high repetition rate, high energy chirped pulse amplification (CPA) system based on single crystal fiber (SCF) amplifier. With home-made all-fiber laser as the seed laser and Yb:YAG rod, SCF as the amplification gain medium, an output power of 61.8 W at 200 kHz repetition rate has been obtained. To the best of our knowledge, this is the highest power based on SCF at hundreds of kHz repetition rate. The measured M2 values are approximately 1.241 in the horizontal and 1.186 in the vertical direction. The spectrum width is 3.8 nm, which support Fourier transform-limited pulse duration of 411 fs. An average power of 41.8 W with pulse duration of 1.5 ps has been obtained after the chirped volume Bragg grating (CVBG) compressor, which will be compressed to hundreds of fs with accurate chirp compensation.

Soil salinity is one of the most serious threats in world agriculture, and often influences cotton growth and development, resulting in a significant loss in cotton crop yield. WRKY transcription factors are involved in plant response to high salinity stress, but little is known about the role of WRKY transcription factors in cotton so far. In this study, a member (GhWRKY34) of cotton WRKY family was functionally characterized. This protein containing a WRKY domain and a zinc-finger motif belongs to group III of cotton WRKY family. Subcellular localization assay indicated that GhWRKY34 is localized to the cell nucleus. Overexpression of GhWRKY34 in Arabidopsis enhanced the transgenic plant tolerance to salt stress. Several parameters (such as seed germination, green cotyledons, root length and chlorophyll content) in the GhWRKY34 transgenic lines were significantly higher than those in wild type under NaCl treatment. On the contrary, the GhWRKY34 transgenic plants exhibited a substantially lower ratio of Na(+)/K(+) in leaves and roots dealing with salt stress, compared with wild type. Growth status of the GhWRKY34 transgenic plants was much better than that of wild type under salt stress. Expressions of the stress-related genes were remarkably up-regulated in the transgenic plants under salt stress, compared with those in wild type. Based on the data presented in this study, we hypothesize that GhWRKY34 as a positive transcription regulator may function in plant response to high salinity stress through maintaining the Na(+)/K(+) homeostasis as well as activating the salt stress-related genes in cells.

In this paper, Uzawa-Low method for three-order block saddle point problem is presented and the corresponding convergence conditions are established. Furthermore, by introducing a preconditioner, we propose centered preconditioned Uzawa-Low method (CPU-Low method) and obtain its convergence conditions as well. Experimental results show that the two proposed methods are more efficient than Uzawa-Low method for the original saddle point problem and the CPU-Low method is superior to the Uzawa-Low method for three-order block saddle point problem.

Two new sesquiterpenes, innatifolone A (1) and pinnatifolone B (2), along with 6 known compounds, furostan (3), isocalamendiol (4), pluviatolide (5), (8S,8'R,9S)-cubebin (6), 2-(4-hydroxy-3-methoxybenzyl)-3-(3,4-dimethoxybenzyl) tetrahydrofuran (7), and methyl 3-acetoxy-12-oleanen-28-oate (8), were isolated from Mongolian herb Syringa pinnatifolia.

LIM-domain proteins play important roles in cellular processes in eukaryotes. In this study, a LIM protein gene, GhWLIM5, was identified in cotton. Quantitative RT-PCR analysis showed that GhWLIM5 was expressed widely in different cotton tissues and had a peak in expression during fiber elongation. GFP fluorescence assay revealed that cotton cells expressing GhWLIM5:eGFP fusion gene displayed a network distribution of eGFP fluorescence, suggesting that GhWLIM5 protein is mainly localized to the cell cytoskeleton. When GhWLIM5:eGFP transformed cells were stained with rhodamine-phalloidin there was consistent overlap in eGFP and rhodamine-palloidin signals, demonstrating that GhWLIM5 protein is colocalized with the F-actin cytoskeleton. In addition, high-speed cosedimentation assay verified that GhWLIM5 directly bound actin filaments, while low cosedimentation assay and microscopic observation indicated that GhWLIM5 bundled F-actin in vitro. Increasing amounts of GhWLIM5 protein were able to protect F-actin from depolymerization in vitro in the presence of Lat B (an F-actin depolymerizer). Our results contribute to a better understanding of the biochemical role of GhWLIM5 in modulating the dynamic F-actin network in cotton.

Cotton stalk was fast pyrolyzed at temperatures between 480 °C and 530 °C in a fluidized bed, and the main product of bio-oil is obtained. The experimental result shows that the highest bio-oil yield of 55 wt% was obtained at 510 °C for cotton stalk. The chemical composition of the bio-oil acquired was analyzed by GC–MS, and its heat value, stability, miscibility and corrosion characteristics were determined. These results showed that the bio-oil obtained can be directly used as a fuel oil for combustion in a boiler or a furnace without any upgrading. Alternatively, the fuel can be refined to be used by vehicles. Furthermore, the energy performance of the pyrolysis process was analyzed. In the pyrolysis system used in our experiment, some improvements to former pyrolysis systems are done. Two screw feeders were used to prevent jamming the feeding system, and the condenser is equipped with some nozzles and a heat exchanger to cool quickly the cleaned hot gas into bio-oil.