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The electrochemical dinitrogen reduction represents an attractive approach of converting N 2 and water into ammonia, while the rational design of catalytic active centers remains challenging. Investigating model molecular catalysts with well-tuned catalytic sites should help to develop a clear structure-activity relationship for electrochemical N 2 reduction. Herein, we designed several polycyclic aromatic hydrocarbon (PAH) molecules with well-defined positions of boron and nitrogen atoms. Theoretical calculations revealed that the boron atoms possess high local positive charge densities as Lewis acid sites, which are beneficial for N 2 adsorption and activation, thus serving as major catalytic active sites for N 2 electrochemical reduction. Furthermore, the close vicinity of two boron atoms can further enhance the local positive density and subsequent catalytic activity. Using the PAH molecule with two boron atoms separated by two carbon atoms (B-2C-B), a high NH 3 production rate of 34.58 μg·h−1·cm−2 and a corresponding Faradaic efficiency (5.86%) were achieved at −0.7 V versus reversible hydrogen electrode, substantially exceeding the other PAHs with single boron or nitrogen-containing molecular structures. [ABSTRACT FROM AUTHOR]

Although several studies on the effects of cadmium (Cd) on wheat have been reported, the gene expression profiles of different wheat tissues in response to gradient concentrations of Cd, and whether soil microorganisms are involved in the damage to wheat remain to be discovered. To gain further insight into the molecular mechanisms of Cd-resistance in wheat, we sowed bread wheat (Triticum aestivum) in artificially Cd-contaminated soil and investigated the transcriptomic response of the wheat roots, stems, and leaves to gradient concentrations of Cd, as well as the alteration of the soil microbiome. Results indicated that the root bioaccumulation factors increased with Cd when concentrations were < 10 mg/kg, but at even higher concentrations, the bioaccumulation factors decreased, which is consistent with the overexpression of metal transporters and other genes related to Cd tolerance. In the Cd-contaminated soil, the abundance of fungal pathogens increased, and the antimicrobial response in wheat root was observed. Most of the differentially expressed genes (DEGs) of wheat changed significantly when the Cd concentration increased above 10 mg/kg, and the transcriptional response is much greater in roots than in stems and leaves. The DEGs are mainly involved in Cd transport and chelation, antioxidative stress, antimicrobial responses, and growth regulation. COPT3 and ZnT1 were identified for the first time as the major transporters responding to Cd in wheat. Overexpression of the nicotianamine synthase and pectinesterase genes suggested that nicotianamine and pectin are the key chelators in Cd detoxification. endochitinase, chitinase, and snakin2 were involved in the anti-fungal stress caused by Cd-induced cell damage. Several phytohormone-related DEGs are involved in the root's growth and repair. Overall, this study presents the novel Cd tolerance mechanisms in wheat and the changes in soil fungal pathogens that increase plant damage. [Display omitted] • Transcriptomics and metagenomics unveil new Cd tolerance mechanisms in wheat. • Cd induced stress in wheat and increased pathogenic fungi in soil. • COPT3 and ZnT1 are key Cd-responsive transporter genes in wheat. • DEGs suggest nicotianamine and pectate as key Cd chelators in wheat. • Roots show higher bioaccumulation and stronger Cd response than stems and leaves. [ABSTRACT FROM AUTHOR]

Porcine epidemic diarrhea virus (PEDV) causes diarrhea, vomiting, and death in piglets. Our previous study has revealed the anti-PEDV activity of Alpiniae oxyphyllae fructus polysaccharide 3 (AOFP3). However, it is still unknown whether AOFP3 can inhibit the replication of PEDV. Therefore, the effect of AOFP3 on PEDV replication was investigated in the present study, along with analysis of viral RdRp activity and expression of hnRNP A1 by RNA polymerase activity assay in vitro, RIP assay, and Western blotting. The results showed that both the PEDV gene and protein levels in IPEC-J2 cells decreased with AOFP3 treatment. In addition, AOFP3 significantly reduced PEDV's replication by down-regulating the activity of PEDV RdRp and reducing the expression of hnRNP A1, whereas only the bind of RdRp to PEDV 3′UTR was inhibited in AOFP3 treated cells. • AOFP3 inhibits PEDV replication in IPEC-J2 cells. • AOFP3 reduces the activity of PEDV RdRp. • AOFP3 reduces the expression of hnRNP A1 in IPEC-J2 cells. • AOFP3 inhibits PEDV RdRp binding to PEDV 3′UTR. [ABSTRACT FROM AUTHOR]