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Abstract Offshore wind power foundations are known to bear complex loadings, not only vertical loading V induced by self-weight, but also horizontal loadings H induced by wind, wave and current, and the bending loading M transferred from superstructure. In this paper a framework for evaluating the bearing capacity of the foundations is presened and the bearing characteristics of offshore wind power foundation under combined horizontal, vertical and bending loadings are analyzed. The bearing capacity of offshore wind power foundation under unidirectional horizontal, vertical and bending loadings is examined, and the relationship between the ultimate bearing capacity and the ratio of diameter to length of pile foundation is obtained. Based on the side-swipe method, the envelope of bearing capacity and failure mode of offshore wind power foundation in V - H , V - M , H - M loading space and V - H - M loading space are studied in details, and the parameter analysis of the envelope of foundation bearing capacity in different loading space are discussed. Finally, a simple and practical method is proposed to judge the stability of the offshore wind power and the seabed. A verification example reveals that the estimates of the presented framework shows good agreement with observations. [ABSTRACT FROM AUTHOR]

• The photo-sensitive micellar systems have improved biodegradability and less toxicity. • Photo-responsive systems based on mixed cationic/anionic surfactants are superior. • Mixed photo-sensitive additives have the advantages of both the constituent additives. • Photo-responsive systems are based on low concentrations of surfactants and additives. A method to construct photo-responsive wormlike micellar systems with high photo-responsive efficiency and strong photo-responsive ability and reduced impact on the environment by mixed cationic/anionic surfactants and mixed photo-sensitive additives has been proposed. For this purpose, a cleavable cationic ester-containing gemini surfactant, N , N '-bis(2-(dodecanoyloxy)ethyl)- N , N , N ', N '-tetramethyl-1,3-propane diammonium dibromide (C 12 DEG 3), and five anionic biocompatible carboxylate surfactants, have been selected. The mixed photo-sensitive additives are composed of sodium trans -ortho-methoxycinnamate (trans -NaOMCA) and sodium trans -cinnamate (trans -NaCA). The mixed cationic/anionic surfactants are superior to the single cationic surfactant C 12 DEG 3 in constructing UV light-responsive wormlike micellar systems due to their stronger self-assembly ability. The molecular structure of anionic surfactant, such as the length of hydrophobic tail, the introduction of the N-methylated amide group between the hydrophobic tail and carboxylate headgroup, and the number of hydroxyl group in bile salts, is important factor influencing the self-assembly ability of the mixed systems. For single C 12 DEG 3 or the mixed cationic/anionic surfactants, the mixed photo-sensitive additives have the advantages of both trans -NaCA and trans -NaOMCA. The fast reaction rate of the trans -to- cis photoisomerization of NaOMCA leads to the high photo-responsive efficiency of the wormlike micellar systems. The addition of t rans -NaCA promotes the growth of wormlike micelles and leads to larger difference between viscosities before and after UV irradiation, demonstrating higher photo-responsive ability. The experimental results reveal that the UV light induced trans -to- cis isomerization of NaOMCA is the main reason inducing the microstructural transition from wormlike micelles to coexistence of spherical and short rodlike micelles and thus causing reduction in shear viscosities by 3–4 orders of magnitude. [ABSTRACT FROM AUTHOR]

Grasslands, the largest carbon pool in China, possess enormous potential for carbon sequestration. Increasing the stomatal aperture to increase the CO 2 absorption capacity is a potential method to improve plant photosynthetic efficiency and ultimately enhance the carbon sequestration capacity of grass plants. Research on stomatal aperture regulation has focused mostly on Arabidopsis or crops, while research on grass plants in these areas is scarce, which seriously restricts the implementation of this grassland carbon sequestration strategy. Here, a widely used ecological grass, centipedegrass, was used as the experimental material. First, a convenient method for observing the stomatal aperture was developed. The leaves were floated in a potassium ion-containing open solution (67 mM KCl, pH 6.0) with the adaxial surface rather than the abaxial surface in contact with the solution and were cultivated under light for 1.5 h. Then, nail polish was applied on the adaxial surface, and a large number of open stomata were imprinted. Second, with the help of this improved method, the concentration‒response characteristics of the stomatal aperture to eleven environmental stimuli were tested. The stomatal aperture is dependent on these environmental stimuli in a concentration-dependent manner. The addition of 100 μM brassinolide led to the maximal stomatal aperture. This study provided a technical basis for manipulating stomatal opening to increase the carbon sequestration capacity of centipedegrass. • Established a convenient method for detecting the stomatal aperture of centipedegrass. • Optimal open solution for the stomatal aperture investigation is 67 mM KCl at pH 6.0 • The addition of 100 μM brassinolide led to the maximal stomatal aperture. [ABSTRACT FROM AUTHOR]

Cynodon dactylon and Zoysia japonica are two important warm-season turfgrass species with multiple utilizations. Genetic transformations of Cynodon dactylon and Zoysia japonica are extremely difficult, which severely restrict the gene functional studies and molecular breeding research of the two grasses. By contrast, virus-induced gene silencing (VIGS) presents an effective and rapid alternative method to create targeted gene knock-outs for gene functional studies in plants. In this study, we tested the efficiency of modified rice tungro bacilliform virus (RTBV) vector in silencing Cynodon dactylon and Zoysia japonica phytoene desaturase ( PDS ) gene through agroinfiltration. The agroinfiltrated leaves of two Cynodon dactylon and two Zoysia japonica cultivars all showed white streaks typical for PDS gene silencing at 21 days post agroinfiltration. In Cynodon dactylon and Zoysia japonica plants displaying white streak leaf symptoms, PDS gene expression in leaves were all significantly lower than that of control and mock-infected plants. These results indicated that RTBV-VIGS system is efficient in Cynodon dactylon and Zoysia japonica . [ABSTRACT FROM AUTHOR]