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The corrosion of slag on refractories usually starts from the matrix, so improving the slag resistance of the matrix is of great significance for the slag resistance of the refractories. To clarify the influence of matrix on the slag resistance of magnesia–carbon refractories, the slag corrosion experiments were conducted at 1873 K on MgO–C refractories, low‐carbon MgO–C refractories, and MgO–SiC–C refractories. The results showed that the slag resistance of MgO–C refractories was higher than that of low‐carbon MgO–C refractories, and the slag resistance of MgO–SiC–C refractories was superior to that of low‐carbon MgO–C refractories. The interaction between MgO–SiC–C refractories and slag generated high melting point phases such as forsterite and spinel, reducing the routes for the slag to infiltrate the inside of the refractories. MgO–SiC–C refractories reacted with slag to increase the viscosity of the slag, the viscosity being 86.3% and 51.9% higher than in the case of low‐carbon MgO–C and MgO–C refractories, respectively. Compared with MgO–SiC–C refractories, MgO–C refractories did not exhibit overwhelming advantages in slag resistance. Due to the low‐carbon content and good slag resistance, MgO–SiC–C refractories were promising low‐carbon magnesia‐based refractories for high‐temperature industries. [ABSTRACT FROM AUTHOR]

Recent studies have revealed that the coagulation system plays a role in mammalian innate defense by entrapping bacteria in clots and generating antibacterial peptides. So, it is very important for the survival of bacteria to defend against the host coagulation system, which suggests that bacterial exotoxins might be a new source of anticoagulants. In this study, we analyzed the genomic sequences of Acinetobacter baumannii and a new bacterial exotoxin protein, F6W77, with five Kunitz-domains, KABP1-5, was identified. Each Kunitz-type domain features a classical six-cysteine framework reticulated by three conserved disulfide bridges, which was obviously similar to animal Kunitz-domain peptides but different from plant Kunitz-domain peptides. Anticoagulation function evaluation showed that towards the intrinsic coagulation pathway, KABP1 and KABP5 had apparently inhibitory activity, KABP4 had weak inhibitory activity, and KBAP2 and KABP3 had no effect even at a high concentration of 20 μg/mL. All five Kunitz-domain peptides, KABP1-5, had no inhibitory activity towards the extrinsic coagulation pathway. Enzyme-inhibitor experiments showed that the high-activity anticoagulant peptide KABP1 had apparently inhibitory activity towards two key coagulation factors, Xa and XIa, which was further confirmed by pull-down experiments that showed that KABP1 can bind to coagulation factors Xa and XIa directly. Structure-function relationship analyses of five Kunitz-type domain peptides showed that the arginine of the P1 site of three new bacterial anticoagulants, KABP1, KABP4 and KABP5, might be the key residue for their anticoagulation activity. In conclusion, with bioinformatics analyses, peptide recombination, and functional evaluation, we firstly found bacterial-exotoxin-derived Kunitz-type serine protease inhibitors with selectively inhibiting activity towards intrinsic coagulation pathways, and highlighted a new interaction between pathogenic bacteria and the human coagulation system. [ABSTRACT FROM AUTHOR]

The thermal decomposition of magnesium hydroxide is key to the preparation of high-quality magnesia-based refractories. As we all know, Mg(OH)2 is the precursor of MgO, so the calcination of Mg(OH)2 has attracted widespread attention. The dehydration process of Mg(OH)2-sol was studied by isothermal thermogravimetric kinetics, and the phase transition process and the variation of the microscopic morphology were mainly characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results showed that the Doyle approximation function and Gorbatchev approximation function were used to calculate the activation energy of the dehydration reaction of Mg(OH)2 to be 69.35 kJ·mol−1 and 65.81 kJ·mol−1, respectively. The sintering temperature was higher than 350°C, and the phase composition and microstructure analysis of the combination indicated that the plate-like structure of Mg(OH)2 had been completely transformed into the cubic structure of MgO.

The ΔN6 truncation is the main posttranslational modification of β2-microglobulin (β2M) found in dialysis-related amyloid. Investigation of the interaction of wild-type (WT) β2M with N-terminally truncated variants is therefore of medical relevance. However, it is unclear which residues among the six residues at the N-terminus are crucial to the interactions and the modulation of amyloid fibril propagation of β2M. We herein analyzed homo- and heterotypic seeding of amyloid fibrils of WT human β2M and its N-terminally-truncated variants ΔN1 to ΔN6, lacking up to six residues at the N-terminus. At acidic pH 2.5, we produced amyloid fibrils in vitro from recombinant, WT β2M and its six truncated variants, and found that ΔN6 β2M fibrils exhibit a significantly lower conformational stability than WT β2M fibrils. Importantly, under more physiological conditions (pH 6.2), we assembled amyloid fibrils in vitro only from recombinant, ΔN4, ΔN5, and ΔN6 β2M but not from WT β2M and its three truncated variants ΔN1 to ΔN3. Notably, the removal of the six, five or four residues at the N-terminus leads to enhanced fibril formation, and homo- and heterotypic seeding of ΔN6 fibrils strongly promotes amyloid fibril formation of WT β2M and its six truncated variants, including at more physiological pH 6.2. Collectively, these results demonstrated that the residues 4 to 6 at the N-terminus particularly modulate amyloid fibril propagation of β2M and the interactions of WT β2M with N-terminally truncated variants, potentially indicating the direct relevance to the involvement of the protein’s aggregation in dialysis-related amyloidosis.

In recent years, with the continuous progress of 3D printing technology, as well as the limitations of traditional preparation methods of porous ceramics, an increasing number of studies on the combination of traditional porous ceramic preparation methods and 3D printing technology for designing and preparing hierarchical porous ceramics with both macropores and micropores have been reported. This is an innovation in the design concept for the manufacturing of porous ceramics. This review focuses on the latest advances in porous ceramics prepared by combined methods, including traditional methods and 3D printing technology, and discusses the design concept and printing process of porous ceramics and the properties of porous ceramics. Case studies of different combination technologies are compared, and the technical features of the combined technologies are summarized. According to the success factors of existing combination technologies, the feasibility of combining traditional porous ceramic preparation methods with different 3D printing technologies is analyzed.