Verticillium wilt, caused by Verticillium dahliae , seriously limits cotton production. It is difficult to control this pathogen damage mainly due to the complexity of the molecular mechanism of plant resistance to V. dahliae . Here, we identified three homologous cotton Walls Are Thin ( WAT ) genes, which were designated as GhWAT1, GhWAT2 , and GhWAT3. The GhWATs were predominantly expressed in the roots, internodes, and hypocotyls and induced by infection with V. dahliae and treatment with indole-3-acetic acid (IAA) and salicylic acid (SA). GhWAT1 -, GhWAT2 -, or GhWAT3 -silenced plants showed a comparable phenotype and level of resistance with control plants, but simultaneously silenced three GhWATs ( GhWAT123 -silenced), inhibited plant growth and increased plant resistance to V. dahliae , indicating that these genes were functionally redundant. In the GhWAT123 -silenced plants, the expression of SA related genes was significantly upregulated compared with the control, resulting in an increase of SA level. Moreover, the histochemical analysis showed that xylem development was inhibited in GhWAT123 -silenced plants compared with the control. However, lignin deposition increased in the xylem of the GhWAT123 -silenced plants compared to the control, and there were higher expression levels of lignin synthesis- and lignifications-related genes in the GhWAT123 -silenced plants. Collectively, the results showed that GhWATs in triple-silenced plants acts as negative regulators of plant resistance against V. dahliae. The potential mechanism of the WATs functioning in the plant defence can modulate the SA biosynthesis and lignin deposition in the xylem.

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Developing new functional applications of metallic glasses in catalysis is an active and pivotal topic for materials science as well as novel environmental catalysis processes. Compared to the crystalline materials with highly ordered atomic packing, metallic glass has a simply disordered atomic structure. Recent reports have demonstrated that the metallic glasses are indeed having many superiorly catalytic properties, yet the understanding of the mechanism is insufficient. In this work, the structural relaxation (α-relaxation) by annealing in an amorphous Fe 78 Si 9 B 13 alloy is studied for unraveling the catalytic mechanism at the atomic scale. The volume fractions of the crystalline structures, such as α-Fe, Fe 2 Si, and Fe 2 B, in the as-received and annealed metallic glasses are fully characterized. It is found that the randomly atomic packing structure with weak atomic bonding in the as-received metallic glass has an efficient electron transfer capability, presenting advanced superiorities in the aspects of production rate of hydroxyl radicals (•OH), dye degradation rate (k), and essential degradation ability (K SA ) for water treatment. The discovery of this critically important work unveils why using metallic glasses as catalysts has higher reactivity than the crystalline materials, and more importantly, it provides new research opportunities into the study of synthetic catalysts.

The corrosion behaviour of CP-Ti and Ti-TiB composite produced by selective laser melting (SLM) in the artificial simulated body fluid (Hank's solution) at body temperature, was investigated systematically by using electrochemical measurements (potentiodynamic polarisation curves and electrochemical impedance spectroscopy), together with some detailed structural characterisations. The results demonstrate that SLM-produced Ti-TiB composite samples possess better corrosion resistance than SLM-produced CP-Ti samples in Hank's solution. Due to these tiny TiB and TiB 2 particles acting as the micro-cathode uniformly distributing in titanium matrix, anodic dissolution of titanium matrix in the corrosion process is prominently facilitated in early stages, followed by rapid passivation on the surface. The corrosion mechanism of Ti-TiB composite samples has also been discussed in detail at the end of this paper.

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