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In the face of environmental pollution and an energy shortage, how to reduce the cost of a noble metal catalyst in clean energy such as the fuel cell system and improve its electrocatalytic performance is one of the hot issues in this field. Here, a facile stepwise co-reduction route for synthesizing a series of PdFe/Cu catalysts with surface reconstruction is investigated and the ethanol oxidation reaction (EOR) performance is explored. The greater exposure of Pd active sites makes it excellent in EOR in alkaline media compared to the homemade and commercial Pd black catalyst. The mass activity of PdFe/Cu (794.97 mA mg−1Pd) is 2.52 times that of the Pd black catalyst (315.64 mA mg−1Pd). This kind of PdFe/Cu catalyst shows enhanced mass current density (255.66 mA mg−1Pd) after the 1800 s chronoamperometry test and only exhibits a decay of 1.4% after accelerated 500-cycle measurement. The enhanced EOR performance may be due to the change in the electronic structure of Pd caused by synergistic and strain effects among Pd, Fe, and Cu. This work provides an effective and kindly strategy to synthesize electrocatalysts with superior activity and durability in relation to EOR.

Helicobacter pylori(H.pylori) infection is a recognized risk factor of dementia, while its role and mechanism in Alzheimer disease (AD) remained unclarified. Our previous study has identified that injection of soluble H.pylorifiltrate could induce AD-like pathologic changes and cognitive impairment in SD rats. In the present study, we further explored the effect of long-term stomach colonization of H.pyloribacteria on the brains of SD rats. The results showed that H.pyloribacteria gavage induced an efficient colonization of H.pyloriin the stomach after four weeks. However, there was no significant change of tau phosphorylation at Thr205 (pT205), Thr231 (pT231), Ser396 (pS396) and Ser404 (pS404) sites in the hippocampus and cerebral cortex. The H.pylori-infected rats also showed no cognitive impairment. These observations may result from inefficient release of bacterial pathogenic factors or the overall lack of host inflammatory responses. We conclude that SD rat with long-term H.pyloricolonization in the stomach is not a suitable animal model for exploring the effects of H.pyloriinfection on brain function in human beings; administration of bacterial filtrates may better reveal the systemic pathologic changes induced by bacterial infection in animals which show a negative host response to bacterial colonization.

This study reports a novel strategy to obtain ultrafine metastable monoclinic molybdenum trioxide (β-MoO3) powder by the method of sublimation in the temperatures range of 1123–1373 K using the industrial grade MoO3as raw material. The vapor-phase MoO3could rapidly condensate and deposit in the bag filter after being quenched. It is found that the particle size has no obvious regularity with the sublimation temperature and the as-prepared β-MoO3appears to be perfectly spherical. Impurities such as SiO2in raw MoO3samples have a significant retarding influence on the sublimation rate. Both the mechanisms of sublimation of industrial grade MoO3as well as the nucleation and growth process of ultrafine β-MoO3have been shed light. This work may have a guide role in the large-scale production of ultrafine spherical β-MoO3catalyst.

In order to remove the hidden danger resulted by distortion of weak surrounding rock in tunnel, the GM(1,1) of the distortion data of weak surrounding rock is used to predict the distortion trend of weak rock vault in the next phase. According to the actual data, a GM(1,1) of the distortion is built, and it is shown that the predict result of GM(1, 1) is accurate, and the calamity can be reduced by the way.

TACI is a member of the tumor necrosis factor receptor superfamily and serves as a key regulator of B cell function. The extracellular domain of a typical TNFR contains multiple copies of CRD, which bind in the monomermonomer interfaces of a trimeric ligand. TACI binds to two ligands, APRIL and BAFF, with high affinity and contains two CRD in its extracellular regions, while BCMA and BR3, contain a single or partial CRD for binding the two ligands. However, TACI can be classified as a single CRD receptor because the amino-terminal CRD1 doesnt contribute to ligand binding. To obtain a new variant of TACI possessing higher affinities for binding, we fused a repeat sequence of CRD2 to the N-terminus of the short form of TACI. The new APRIL antagonist peptide, CRD2-shortTACI-Fc, was designed based on the modeling 3-D complex structure of TACI and APRIL. As expected, the purified recombinant CRD2-shortTACI-Fc fusion protein could bind to APRIL in vitro and demonstrated dose-dependent inhibition of APRIL-induced proliferative activity in Raji cells. We found that CRD2-shortTACI-Fc, has a higher affinity for binding to ligands than short-TACI-Fc, which contains a single CRD2.