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Using choline chloride-ethylene glycol (CC-EG) to partially replace the water solvent, taking relative crystal purity(RCP) as the experimental index,and according to the 7-factor 12-level uniform design scheme, high crystallinity and purity M-type barium ferrite (BaFe12O19) was prepared by chemical co-precipitation method. The RCP of each sample was calculated by performing peak fitting on the XRD spectrum of the prepared sample, and then a regression model was established between RCP and the main synthesis factors(Fe/Ba molar ratio, CC-EG content,pH value, resting time, pre-calcination temperature, calcination temperature, calcination time) through quadratic polynomial stepwise regression analysis. According to the regression model, the primary and secondary order of each item in the model, the primary and secondary order of factors and the interaction between factors were investigated, and the feasibility of introducing CC-EG into the BaFe12O19 synthesis process to improve its RCP value was revealed. The results of optimal level combination analysis and verification experiments further show that partial replacement of water solvent with CC-EG can improve the crystallization order of BaFe12O19 and reduce its microscopic strain, thus significantly improve its RCP. The XRD, SEM and VSM analysis results show that the increase of RCP obviously contributes to the radial size and saturation magnetization of BaFe12O19. BaFe12O19 with good properties can be prepared by choline chloride-ethylene glycol-water medium. [ABSTRACT FROM AUTHOR]

Spinal muscular atrophy (SMA) is a neuromuscular disorder due to degeneration of spinal cord motor neurons caused by deficiency of the ubiquitously expressed SMN protein. Here, we present a retinal vascular defect in patients, recapitulated in SMA transgenic mice, driven by failure of angiogenesis and maturation of blood vessels. Importantly, the retinal vascular phenotype was rescued by early, systemic SMN restoration therapy in SMA mice. We also demonstrate in patients an unfavorable imbalance between endothelial injury and repair, as indicated by increased circulating endothelial cell counts and decreased endothelial progenitor cell counts in blood circulation. The cellular markers of endothelial injury were associated with disease severity and improved following SMN restoration treatment in cultured endothelial cells from patients. Finally, we demonstrated autonomous defects in angiogenesis and blood vessel formation, secondary to SMN deficiency in cultured human and mouse endothelial cells, as the underlying cellular mechanism of microvascular pathology. Our cellular and vascular biomarker findings indicate microvasculopathy as a fundamental feature of SMA. Our findings provide mechanistic insights into previously described SMA microvascular complications, and highlight the functional role of SMN in the periphery, including the vascular system, where deficiency of SMN can be addressed by systemic SMN-restoring treatment., Introduction Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder caused, in approximately 95% of patients, by homozygous deletion of the survival motor neuron 1 gene (SMN1) (1). The [...]

Rod-shaped CoFe2O4 was prepared by chemical precipitation-topotactic reaction method, and in this preparation needle-like γ-FeOOH and α-FeOOH were synthesized to use as template materials. The evolution of phase and morphology in the process of calcination exhibits that α-FeOOH and γ-FeOOH experienced different routes to form the α-Fe2O3 middle phase with different crystallinity and morphology. The synthesis process of CoFe2O4 revealed that the crystallinity, purity and morphology of CoFe2O4 depend on the α-Fe2O3 middle phase. The magnetic measurement showed that the CoFe2O4 prepared from α-FeOOH has higher saturation magnetization and coercivity, and the crystallinity and morphology may play important roles in achieving a better magnetic performance. [ABSTRACT FROM AUTHOR]

Plate-shaped ZnW ferrites were prepared by chemical co-precipitation method and sol-gel auto-combustion method, respectively, and their precursors, calcination processes and final products were comparatively studied. The results showed the ZnW ferrites prepared by chemical co-precipitation method and sol-gel auto-combustion method to present different crystallinities, radial sizes, and aspect ratios, which originate from the preparation procedure of the precursors and formation routes of ZnW ferrites. The magnetic measurement confirmed that the ZnW ferrite prepared by sol-gel auto-combustion method presents higher saturation magnetization and coercivity, and the analysis indicated that the crystallinity of ZnW ferrite plays an important role to achieve better magnetic performance. Graphical abstract: [ABSTRACT FROM AUTHOR]