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As the use time of concrete structures increases, defects such as concrete cracks, corrosion and exposure of steel bars gradually appear, resulting in additional repair of concrete structures to increase their durability and life. In this article, the effects of nano-modified polymer cement-based materials as repair material on the bending behavior of repaired concrete beams were studied. Based on the moment, deflection, strain, surface quality and cracking development monitor of repaired concrete beams, the bending behavior of repaired beams with polymer, nano-modified polymer and fibers was compared and the failure mechanism of the beams was analyzed. The results showed that the nano-modified polymer cement-based materials are helpful in improving the performance of repaired beams, manifested by the increase in the ultimate bending moment and the significant improvement in the quality of the interface between repair and matrix concrete. Compared with polymer cement-based materials, nano-modified polymer cement-based materials result in a 27% increase in ultimate bending moment of the repaired beam and a 58% increase in cracking moment, while reducing the total number of cracks by 23% and the average width of cracks by 17% in the repaired beam. This article demonstrated the availability of nanomaterials for improving the loading behavior of structural components with polymer-modified cement-based materials.

Here, we reported a novel secreted protein elicitor PeBL2 from Brevibacillus laterosporus A60, which can induce hypersensitive response in tobacco (Nicotiana benthamiana). The ion-exchange chromatography, high-performance liquid chromatography (HPLC) and mass spectrometry were performed for identification of protein elicitor. The 471 bp PeBL2 gene produces a 17.22 kDa protein with 156 amino acids containing an 84-residue signal peptide. Consistent with endogenous protein, the recombinant protein expressed in Escherichia coli induced the typical hypersensitive response (HR) and necrosis in tobacco leaves. Additionally, PeBL2 also triggered early defensive response of generation of reactive oxygen species (H2O2 and O2-) and systemic resistance against of B. cinerea. Our findings shed new light on a novel strategy for biocontrol using B. laterosporus A60.

Via a simple sol-gel approach, the high photocatalytic efficiency of Bi1-xSmxFeO3 nanoparticles were realized when x was 0, 0.05, 0.10, 0.15 and 0.20. Microstructural characterizations including X-ray diffraction (XRD) spectroscopy, Raman spectroscopy, field emission scanning electron microscope (FESEM), x-ray photoelectron spectroscopy (XPS) and ultraviolet-visible (UV-Vis) spectrophotometer, demonstrated a transformation from the rhombohedral structure of BiFeO3 to the orthorhombic structure of Bi0.80Sm0.20FeO3. Moreover, the experimental findings discovered that the photocatalytic efficiency of Bi0.80Sm0.20FeO3 was the highest, reaching 98.5% within 2 h based on visible light degradation. The underlying mechanisms, involved to phase transition, size effect, band energy and Fenton reaction, were discussed. The research presented in the paper is crucial in offering a fundamental strategy for utilizing BiFeO3 to address the issue of water pollutants. Highlights: Bi1-xSmxFeO3 nanoparticles with varying Sm doping levels (x = 0, 0.05, 0.10, 0.15, and 0.20) were successfully synthesized in this study. X-ray diffraction and Raman spectroscopy demonstrated that the transformation of the rhombohedral crystal structure (R3c space group) to the orthorhombic structure (Pnma space group) in Bi0.80Sm0.20FeO3. Experimental results indicated that the photocatalytic efficiency of Bi0.80Sm0.20FeO3 reach to 98.5%, with superior chemical stability. These findings offer a fundamental strategy for utilizing BiFeO3 in addressing water pollutant issues. [ABSTRACT FROM AUTHOR]

Glycosaminoglycans (GAGs) with unique structures from marine animals show intriguing pharmacological activities and negligible biological risks, providing more options for us to explore safer agents. The swim bladder is a tonic food and folk medicine, and its GAGs show good anticoagulant activity. In this study, two GAGs, CMG-1.0 and GMG-1.0, were extracted and isolated from the swim bladder of Cynoscion microlepidotus and Gadus morhua. The physicochemical properties, precise structural characteristics, and anticoagulant activities of these GAGs were determined for the first time. The analysis results of the CMG-1.0 and GMG-1.0 showed that they were chondroitin sulfate (CS)/dermatan sulfate (DS) hybrid chains with molecular weights of 109.3 kDa and 123.1 kDa, respectively. They were mainly composed of the repeating disaccharide unit of -{IdoA-α1,3-GalNAc4S-β1,4-}- (DS-A). The DS-B disaccharide unit of -{IdoA2S-α1,3-GalNAc4S-β1,4-}- also existed in both CMG-1.0 and GMG-1.0. CMG-1.0 had a higher proportion of CS-O disaccharide unit -{-GlcA-β1,3-GalNAc-β1,4-}- but a lower proportion of CS-E disaccharide unit -{-GlcA-β1,3-GalNAc4S6S-β1,4-}- than GMG-1.0. The disaccharide compositions of the GAGs varied in a species-specific manner. Anticoagulant activity assay revealed that both CMG-1.0 and GMG-1.0 had potent anticoagulant activity, which can significantly prolong activated partial thromboplastin time. GMG-1.0 also can prolong the thrombin time. CMG-1.0 showed no intrinsic tenase inhibition activity, while GMG-1.0 can obviously inhibit intrinsic tenase with EC50 of 58 nM. Their significantly different anticoagulant activities may be due to their different disaccharide structural units and proportions. These findings suggested that swim bladder by-products of fish processing of these two marine organisms may be used as a source of anticoagulants. [ABSTRACT FROM AUTHOR]