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• We proposed an innovative clamp reinforcing technique for the main leg and diagonal members of operational transmission towers. • We conducted an experiment on transmission tower reinforced with clamps. • We analyzed the synergy between the original and retrofitting members in the reinforced transmission tower. • We analyzed the failure modes of a transmission towers under wind loads based on an experiment, and compared the numerical simulation and experimental results. • Further, We developed formulas for computing the ultimate loads of reinforced compound members under eccentric compression. Transmission towers frequently collapse under extreme weather conditions such as strong winds. To ensure the stability of existing transmission towers, we propose an innovative clamp reinforcing technique for the main leg and diagonal members of operational transmission towers. This technique employs star-shaped plates with stiffeners, angle steel clamps, connecting plates, and bolts to connect the reinforcing members to the original members of the transmission tower without drilling or welding. It was demonstrated by performing sub-assemblage tests that the ultimate bearing capacity of the reinforced structure can be enhanced by 21.96% compared with the original structure while maintaining a strong synergy between the reinforcing and original members. Finally, a formula for computing the ultimate loads of reinforced compound members under eccentric compression is proposed along with a method for calculating the section coefficient, and 40 sets of eccentric compressed members were employed as samples for verification. The findings of the study can serve as a theoretical analysis basis for the retrofitting design of transmission towers. [ABSTRACT FROM AUTHOR]

Drought is one of the hot topics needing urgent attention in the current era of climate change. It massively disturbs the rice growth and productivity and is becoming a serious threat. The drought avoidance strategies in rice include stomatal closure, cellular adaptation and changes in root development. Moreover, the endogenous plant hormones (abscisic acid and jasmonic acid) and reactive oxygen species have paramount importance in drought tolerance in rice. The drought tolerance induces modification in biochemical, molecular and physiological properties of plants. At the molecular level, expression of several transcription-factors is modulated which further determine the activation of drought responsive gene families. Mitogen activated protein kinases and Ca signaling pathways initiate an array of signaling cascade for mediating the gene expression in rice. Approaches, conventional breeding methods combined with modern emerging techniques such as genetic engineering, to improve rice drought tolerance were discussed. This review provided recent insights into major regulatory factors against drought stress, signaling mechanisms and molecular engineering strategies (including conventional transgenic and recent genome editing approaches) to induce drought tolerance in rice. [ABSTRACT FROM AUTHOR]

Offering the advantages of non-combustibility, high shear strength, and high shear stiffness, a cold-formed steel (CFS) shear wall sheathed with corrugated steel sheets (CSS) is a promising shear wall system for low- and mid-rise constructions in high wind and seismic zones. As the primary lateral force-resistant component of CFS structures, the lateral response of CSS sheathed shear wall is primarily determined by the CFS-to-sheathing screwed connections. The connection performance of screws in CFS walls was determined by a combination of shear and tensile forces, with a particular focus on the shear performance parallel to the corrugation direction within the plane. The series of experiments reported in this paper characterize the hysteretic behavior of the screwed connections between CFS studs and sheathing panel under shear loading. Experimental tests were conducted in order to generate the hysteretic responses of CFS-to-CSS screwed connections with varied sheathing panel types, sheathing thicknesses, screw spacings, and edge distances. The results indicated that the test phenomena observed in the screwed connection between CFS and sheathing panel during the entire loading process were generally a combination of several failure modes, which was predominantly influenced by the sheathing thickness, the end distance, and the loading method. The peak load of the specimens under monotonic loading were greater than that under cyclic loading and increased almost linearly with the increase in sheathing thickness. Referring to North American code provisions, a calculation method for the strength of CFS-to-CSS screwed connections was proposed. Finally, based on the experimental data, a hysteretic constitutive model for CFS-to-CSS screwed connection was established. This model serves as preliminary preparation for the refined numerical simulation of corrugated steel sheathed shear wall. • The hysteretic performance of CFS-to-CSS screwed connections was investigated experimentally. • The test phenomena and failure modes of theCFS-to-CSS screwed connections were explored. • A hysteretic constitutive model for CFS-to-CSS screwed connections was established based on test data. [ABSTRACT FROM AUTHOR]