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Formation of the vascular cylinder, a structure critical to water and nutrient transport in higher plants, is highly regulated. Here we identify WRKY15 as an important regulator that suppresses tracheary element (TE) differentiation in Arabidopsis thaliana. Overexpression of WRKY15 resulted in discontinuous protoxylem vessel files and TEs with reduced spiral wall thickening/lignification. Expression of a dominant-negative WRKY15 variant, WRKY15-EAR, led to extra protoxylem vessels and ectopic TEs with increased spiral wall thickening/lignification. Ectopic TE formation in the root cortex and hypocotyl/leaf epidermis reveals that the suppression of WRKY15 is sufficient to trigger the transdifferentiation of other

A mathematical model for heavy metal contaminants (HMCs) transport in a triple-layer composite liner with defective geomembrane under the non-isothermal condition is developed in this study, where the GMB/GCL/CCL (geomembrane, geosynthetic clay liner, and compacted clay liner) composite liner is adopted as an example and the Langmuir adsorption model is incorporated. The proposed model is solved by the finite difference approach, and its correctness is validated by comparison with the experimental results, an existing analytical solution, and another numerical method. Later, the transport behaviors of HMCs are explored with the established model. Compared with the isothermal condition, the non-isothermal condition enlarges the transport flux, but also reduces the concentration of HMCs. The relative concentration based on the Langmuir adsorption model is higher than that based on the linear adsorption model, which is related to the decrease of the retardation factor under the Langmuir adsorption model. Furthermore, the parametric study shows that when the leachate head ht is between 1.0 and 3.0 m, the defined breakthrough time tb increases by about 1.57 a with the increase of GCL thickness lg by 1 cm, and the tb increases by about 9.07 a with the increase of CCL thickness lc by 0.1 m.