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The proportion of pellets in the blast furnace charge structure is gradually increasing, among which magnesium-bearing fluxed pellets have been widely applied due to their excellent metallurgical properties. To further determine the consolidation mechanism in different reaction layers of magnesium-bearing fluxed pellets, the phase transformation and diffusion behaviors of Fe3O4–MgO in different roasting atmospheres were investigated in this study. The results showed that Fe2+ preferentially diffused to the MgO layer and combined with Mg2+ to form MgyFe1−yO in inert atmosphere, and then, Fe3+ and Fe2+ binded to Mg2+ to form [(MgO)x(FeO)1−x]·Fe2O3 (0 ≤ x ≤ 1). The increase of roasting temperature was favorable for the entry of Mg2+ into the spinel phase. In air atmosphere, Fe3O4 was first oxidized to Fe2O3. Fe3+ and Mg2+ counter-diffused and then combined to MgxFe3−xO4 (x = 1). Fe3O4 reacted more readily with MgO in inert atmosphere than in air atmosphere. It was favorable to increase the oxygen partial pressure for MgxFe3−xO4 (x = 1) generation. The diffusion rate of Mg2+ at the interface of Fe3O4–MgO system in inert atmosphere was 1.88 µm/min at 1200 °C, which was faster than that of 1.49 µm/min in air atmosphere. [ABSTRACT FROM AUTHOR]

The transplantation of bone marrow mesenchymal stem cells (MSCs) in stroke is hindered by the restricted rates of survival and differentiation. Ginsenoside compound K (CK), is reported to have a neuroprotective effect and regulate energy metabolism. We applied CK to investigate if CK could promote the survival of MSCs and differentiation into brain microvascular endothelial‐like cells (BMECs), thereby alleviating stroke symptoms. Therefore, transwell and middle cerebral artery occlusion (MCAO) models were used to mimic oxygen and glucose deprivation (OGD) in vitro and in vivo, respectively. Our results demonstrated that CK had a good affinity for GLUT1, which increased the expression of GLUT1 and the production of ATP, facilitated the proliferation and migration of MSCs, and activated the HIF‐1α/VEGF signaling pathway to promote MSC differentiation. Moreover, CK cooperated with MSCs to protect BMECs, promote angiogenesis and vascular density, enhance neuronal and astrocytic proliferation, thereby reducing infarct volume and consequently improving neurobehavioral outcomes. These results suggest that the synergistic effects of CK and MSCs could potentially be a promising strategy for stroke. [ABSTRACT FROM AUTHOR]

Sheath blight (ShB) disease, caused by Rhizoctonia solani Kühn, is one of the most serious rice diseases. Rice breeding against ShB has been severely hindered because no major resistance genes or germplasms are available in rice. Here, we report that introduction of Gastrodia antifungal protein (GAFP) genes from Gastrodia elata B1 into rice significantly enhances resistance to rice ShB. Four GAFP genes were cloned from G. elata B1, and all displayed a strong ability to inhibit R. solani growth in plate assays. Two versions, with or without a signal peptide, for each of the four GAFP genes were introduced into XD3 and R6547 rice cultivars, and all transgenic lines displayed stronger ShB resistance than the corresponding wild-type control in both greenhouse and field conditions. Importantly, GAFP2 showed the highest ShB resistance; GAFPs with and without its signal peptide showed no significant differences in enhancing ShB resistance. We also evaluated the agronomic traits of these transgenic rice and found that ectopic expression of GAFPs in rice at appropriate levels did not affect agronomic traits other than enhancing ShB resistance. Together, these results indicate that GAFP genes, especially GAFP2, have great potential in rice breeding against ShB disease. [ABSTRACT FROM AUTHOR]