Magnetic properties and rare earth element diffusion behavior of hot-deformed nanocrystalline dual-main-phase Nd-Ce-Fe-B magnets.

To inhibit the magnetic dilution effect of Ce in Nd-Ce-Fe-B magnets, a dual-alloy method is employed to prepare hot-deformed dual-main-phase (DMP) magnets using mixed nanocrystalline Nd-Fe-B and Ce-Fe-B powders. A REFe2 (1 : 2, where RE is a rare earth element) phase can only be detected when the Ce-Fe-B content exceeds 30 wt%. The lattice parameters of the RE2Fe14B (2 : 14 : 1) phase exhibit non-linear variation with the increasing Ce-Fe-B content due to the mixed valence states of Ce ions. Owning to inferior intrinsic properties of Ce2Fe14B compared to Nd2Fe14B, the magnetic properties of DMP Nd-Ce-Fe-B magnets almost decrease with the increase of Ce-Fe-B addition, but interestingly, the magnet with 10 wt% Ce-Fe-B addition exhibits an abnormally increased intrinsic coercivity H cj of 1215 kA m-1, together with the higher temperature coefficients of remanence (α = -0.110%/K) and coercivity (ß = -0.544%/K) in the temperature range of 300-400 K than the single-main-phase (SMP) Nd-Fe-B magnet with H cj = 1158 kA m-1, α = -0.117%/K and ß = -0.570%/K. The reason may be partly attributed to the increase of Ce3+ ions. Different from the Nd-Fe-B powders, the Ce-Fe-B powders in the magnet are difficult to deform into a platelet-like shape because of the lack of low melting point RE-rich phase due to the precipitation of the 1 : 2 phase. The inter-diffusion behavior between the Nd-rich region and Ce-rich region in the DMP magnets has been investigated by microstructure analysis. The significant diffusion of Nd and Ce into Ce-rich and Nd-rich grain boundary phases, respectively, was demonstrated. At the same time, Ce prefers to stay in the surface layer of Nd-based 2 : 14 : 1 grains, but less Nd diffuses into Ce-based 2 : 14 : 1 grains due to the 1 : 2 phase presented in the Ce-rich region. The modification of the Ce-rich grain boundary phase by Nd diffusion and the distribution of Nd in the Ce-rich 2 : 14 : 1 phase are beneficial for magnetic properties.

Involvement of plasma lncRNA GSEC in sepsis discrimination and prognosis, and its correlation with macrophage cell inflammation and proliferation.

BACKGROUND: Despite the dysregulation and function of G-quadruplex-forming sequence containing lncRNA (GSEC) have been widely reported in human cancers, there are few available data revealing its role in sepsis. OBJECTIVE: To assess the expression and function of GSEC in the development of sepsis and its potential molecular mechanism. MATERIALS AND METHODS: A total of 78 sepsis patients, 55 non-sepsis intensive care unit patients, and 42 healthy individuals were enrolled in this study. The expression of GSEC was evaluated in plasma and macrophage cells with polymerase chain reaction. The inflammation response of sepsis patients and macrophage cells was analyzed with an enzyme-linked immunosorbent assay. The diagnostic and prognostic value of GSEC in sepsis patients were estimated by receiver operator curve (ROC) and Cox analysis. The molecular mechanism underlying the function of GSEC was investigated in RAW264.7 cell with luciferase reporter assay and cell transfection. RESULTS: Significant upregulation of GSEC was observed in sepsis patients' plasma, which could discriminate sepsis patients from healthy and non-sepsis individuals. Upregulation of GSEC was positively correlated with inflammation cytokine levels and adverse prognosis of sepsis patients. In vitro, GSEC was found to modulate the expression level of miR-873-3p, which mediated the regulatory effect of GSEC on the inflammation and proliferation of RAW264.7. CONCLUSION: Upregulated GSEC could serve as a biomarker of sepsis pathogenesis and development. GSEC regulates the inflammation and proliferation of macrophage cells through modulating miR-873-3p.

Dual Utilization of Lignocellulose Biomass and Glycerol Waste to Produce Fermentable Levoglucosan via Fast Pyrolysis.

Glycerol waste was combined with microwave to pretreat lignocellulose before fast pyrolysis. After pretreatment, most alkali and alkaline earth metals (87.9%) and lignin (52.6%) were removed, and a higher crystallinity was obtained. Comparatively, glycerol waste combined with microwave was proven to be more efficient than glycerol with conventional heating. During fast pyrolysis, higher content of levoglucosan in glycerol waste-pretreated products (27.5%) was obtained, compared with those pretreated by pure glycerol (18.8%) and untreated samples (5.8%). Production of fermentative toxic aldehyde and phenol by-products was also inhibited after glycerol waste treatment. Following mechanistic study had validated that microwave in glycerol waste solvent could effectively ameliorate structure and components of lignocellulose while selectively removing lignin. Notably, under the optimal condition, the levoglucosan content in pyrolytic products was enhanced significantly from 5.8% to 32.9%. In short, this study provided an archetype to dually utilize waste resources for ameliorating lignocellulose structure and precisely manipulating complex fast pyrolysis.

Novel crude glycerol pretreatment for selective saccharification of sugarcane bagasse via fast pyrolysis.

Pretreatment is a vital process for efficient saccharification and utilization of lignocellulose. In this study, crude glycerol derived from biodiesel production was used for pretreatment to facilitate selective saccharification via fast pyrolysis. Due to the efficient removal of alkali and alkaline earth metals (>95.0%) and lignin (79.4%) by crude glycerol pretreatment, the yield of levoglucosan was evaluated to 25.2% as compared to those from pure glycerol pretreated (14.4%) and untreated sugarcane bagasse (8.4%). Meanwhile, the production of inhibitors (e.g. acetic acid, phenol) to biocatalysts was also obviously inhibited from crude glycerol pretreated biomass. Consequently, this work provided a cost-effective and eco-friendly pretreatment mode, which could not only make full utilization of crude glycerol, but also improve the fermentability of lignocellulosic pyrolysate.

MicroRNA­216b inhibits cell proliferation and invasion in glioma by directly targeting metadherin.

Glioma is a well­known aggressive and malignant brain tumor, and accounts for ~30% of all brain and central nervous system tumors. A number of studies have indicated that the abnormal expression of specific microRNAs (miR) serves vital roles in the tumorigenesis and tumor development of human cancer, including glioma. miR­216b has been studied in a number of types of cancer. However, the expression pattern, molecular function and underlying mechanisms of miR­216b in glioma remain unclear. In the present study, it was demonstrated that the level of miR­216b was significantly decreased in glioma tissues and cell lines compared with matched normal tissues and primary normal human astrocytes. The reduced miR­216b expression level was correlated with the Karnofsky Performance Score and the World Health Organization grade of gliomas. Upregulation of miR­216b repressed cell proliferation and invasion in glioma. Additionally, metadherin (MTDH) was identified as a direct target gene of miR­216b in glioma. MTDH expression was demonstrated to be significantly upregulated and inversely associated with miR­216b expression in glioma specimens. MTDH knockdowns could simulate the cellular conditions induced by miR­216b overexpression in glioma cells. In addition, miR­216b regulated phosphatidylinositol 3,4,5­trisphosphate 3­phosphatase and dual­specificity protein phosphatase PTEN/protein kinase B signaling pathways in glioma. These results suggested that miR­216b acted as a tumor suppressor in glioma by directly targeting MTDH and that the miR­216b/MTDH axis may be an effective therapeutic target for the treatment of patients with this disease.