B-Site Super-Excess Design Sr2V0.4Fe0.9Mo0.7O6-δ-Ni0.4 as a Highly Active and Redox-Stable Solid Oxide Fuel Cell Anode.

In-situ exsolution type perovskites as solid oxide fuel cell (SOFCs) anode materials have received widespread attention because of their excellent catalytic activity. In this study, excessive NiO is introduced to the Sr2V0.4Fe0.9Mo0.7O6-δ (SVFMO) perovskite with the B-site excess design, and in-situ growth of FeNi3 alloy nanoparticles is induced in the reducing atmosphere to form the Sr2V0.4Fe0.9Mo0.7O6-δ-Ni0.4 (SVFMO-Ni0.4) composite anode. Here, with H2 or CH4 as SOFCs fuel gas, the formation of FeNi3 nanoparticles further enhances the catalytic ability. Compared with SVFMO, the maximum power density (Pmax) of Sr2V0.4Fe0.9Mo0.7O6-δ-Ni0.4 (SVFMO-Ni0.4) increases from 538 to 828 mW cm-2 at 850 °C with hydrogen as the fuel gas, and the total polarization resistance (RP) decreases from 0.23 to 0.17 Ω cm2. In addition, the long-term operational stability of the SVFMO-Ni0.4 anode shows no apparent performance degradation for more than 300 h. Compared with SVFMO, the Pmax of SVFMO-Ni0.4 increases from 138 to 464 mW cm-2 with methane as fuel gas, and the RP decreases from 1.21 to 0.29 Ω cm2.

The protective effects of walnut green husk polysaccharide on liver injury, vascular endothelial dysfunction and disorder of gut microbiota in high fructose-induced mice.

This study aimed to investigate the protective effects of walnut green husk polysaccharide (WGHP) on liver injury, vascular endothelial dysfunction and disorder of gut microbiota in mice induced by high fructose (HF) diet. The chemical analysis results show that the walnut green husk polysaccharide is a low molecular weight acidic heteropolysaccharide, composed mainly of glucuronic acid, arabinose and galactose. Biochemical analysis showed that WGHP significantly improved glucose metabolism and lipid metabolism and decreased oxidative stress in HF-diet induced obesity mice. Histopathological observation of liver and cardiovascular aorta confirmed the protective effects of WGHP on hepatic steatosis and vascular endothelial dysfunction. Furthermore, 16S rRNA sequencing results demonstrated that WGHP reversed the disorders of gut microbiota caused by HF, decreased the relative abundance of Verrucomicrobia and increased the relative abundance of Deferribacteres at the phylum level, decreased the relative abundance of Akkermansia, Lachnoclostridium and norank_f__Muribaculaceae and increased the relative abundance of Prevotellaceae_UCG-001, Helicobacter, Alloprevotella and Allobaculum at the genus levels. Our results indicate that WGHP may act as a functional polysaccharide for protecting liver and cardiovascular in HF-fed mice.

Physiological characterization of maize tolerance to low dose of aluminum, highlighted by promoted leaf growth.

MAIN CONCLUSION: Effects of a low aluminum (Al) dose were characterized. The Al supplement inhibited root growth but enhanced leaf growth in maize lines with different Al sensitivities. High levels of Al are phytotoxic especially in acidic soils. The beneficial effects of low Al levels have been reported in some plant species, but not in maize. Maize is relatively more sensitive to Al toxicity than other cereals. Seedlings, at the three leaf stage, of four Chinese maize foundation parent inbred lines with different Al tolerances, were exposed to complete Hoagland's nutrient solution at pH 4.5 supplemented with 48 µM Al(3+) under controlled growth conditions, and then the Al stress (AS) was removed. The leaf and root growth, root cell viability, superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ions (K(+), Ca(++) and Mg(++)), photosynthetic rate and chlorophyll, protein and malondialdehyde contents in tissues were assayed. In conclusion, a low Al dose inhibits root growth but enhances leaf growth in maize. The Al-promoted leaf growth is likely a result of increased protein synthesis, a lowered Ca(++) level, and the discharge of the growth-inhibitory factors. The Al-promoted leaf growth may be a 'memory' effect caused by the earlier AS in maize. Al causes cell wall rupture, and a loss of K(+), Ca(++) and Mg(++) from root cells. CAT is an auxiliary antioxidant enzyme that works selectively with either SOD or POD against AS-related peroxidation, depending on the maize tissue. CAT is a major antioxidant enzyme responsible for root growth, but SOD is important for leaf growth during AS and after its removal. Our results contribute to understanding how low levels of Al affect maize and Al-resistant mechanisms in maize.

Mechanisms of progressive water deficit tolerance and growth recovery of Chinese maize foundation genotypes Huangzao 4 and Chang 7-2, which are proposed on the basis of comparison of physiological and transcriptomic responses.

The maize inbred lines Huangzao 4 (HZ4) and Chang 7-2 (C7-2) are the foundation genotypes key to maize cross-breeding in China. C7-2 is derived from HZ-4. In this study, changes in phenotype, physiology and gene expression of three-leaf-old seedlings of HZ4 and C7-2 under the conditions of progressive water deficit (WD) and re-watering (RW) were compared to gain knowledge for breeding new maize foundation genotypes with higher drought tolerance. Progressive WD was produced by adding polyethylene glycol (PEG 6000) at 24 h intervals (24, 48 and 72 h) in Hoagland's nutrient solution, resulting in water potentials of -0.15, -0.3 and -0.5 MPa. The seedlings treated for 24 h at -0.5 [corrected] MPa were subjected to RW in the solution without complementation with PEG. The results showed that C7-2 seedlings are more tolerant to progressive WD than HZ4 seedlings in part because the former have a larger stomatal resistance, a relatively stronger leaf water-holding capacity, and a timely and stable increase in activities of antioxidant enzymes (superoxide dismutase and peroxidase) especially in roots upon WD. Oligonucleotide probe array-based analysis uncovered a number of WD- and RW-regulated genes in both inbred lines, and clearly indicated that fine transcriptional coordination between maize leaves and roots is one of the factors constituting higher WD tolerance and a greater ability for growth recovery from WD. On the basis of the resulting data and co-regulation of responsive genes in tissues, we propose a model for the whole maize plant tolerance to growth and recovery from WD.