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Alveolar bone regeneration has been strongly linked to macrophage polarization. M1 macrophages aggravate alveolar bone loss, whereas M2 macrophages reverse this process. Berberine (BBR), a natural alkaloid isolated and refined from Chinese medicinal plants, has shown therapeutic effects in treating metabolic disorders. In this study, we first discovered that culture supernatant (CS) collected from BBR-treated human bone marrow mesenchymal stem cells (HBMSCs) ameliorated periodontal alveolar bone loss. CS from the BBR-treated HBMSCs contained bioactive materials that suppressed the M1 polarization and induced the M2 polarization of macrophages in vivo and in vitro. To clarify the underlying mechanism, the bioactive materials were applied to different animal models. We discovered macrophage colony-stimulating factor (M-CSF), which regulates macrophage polarization and promotes bone formation, a key macromolecule in the CS. Injection of pure M-CSF attenuated experimental periodontal alveolar bone loss in rats. Colony-stimulating factor 1 receptor (CSF1R) inhibitor or anti-human M-CSF (M-CSF neutralizing antibody, Nab) abolished the therapeutic effects of the CS of BBR-treated HBMSCs. Moreover, AKT phosphorylation in macrophages was activated by the CS, and the AKT activator reversed the negative effect of the CSF1R inhibitor or Nab. These results suggest that the CS of BBR-treated HBMSCs modulates macrophage polarization via the M-CSF/AKT axis. Further studies also showed that CS of BBR-treated HBMSCs accelerated bone formation and M2 polarization in rat teeth extraction sockets. Overall, our findings established an essential role of BBR-treated HBMSCs CS and this might be the first report to show that the products of BBR-treated HBMSCs have active effects on alveolar bone regeneration. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to relate the altitudinal and vertical distributions and occurrences of major heavy metals (HMs) to soil physicochemical properties in the riparian soils subject to periodic and intense wet–dry cycles Materials and methods: Cadmium (Cd), copper (Cu), and lead (Pb) and their chemical fractions were investigated in the riparian soil (0–40 cm) of the upland and within the water-level-fluctuation zone (WLFZ) at two tributary backwaters of the Three Gorges Reservoir (TGR) in China. Selected soil basic properties and pore structures determining the distribution of HMs and their fractions were identified using correlation and redundancy analysis Results and discussions: Cd showed moderate–strong contamination and prevailed in non-residual fraction (>73.2%) in the riparian soil of the tributary backwaters in the TGR. In contrast, Cu and Pb exhibited slight contamination and prevailing in residual fraction (>50.3%). Enrichment of HMs in the lower end relatively flat WLFZ where flow rate decreased abruptly and dramatically was observed. Cd exhibited the largest coefficient of variation (CV, up to 0.263) across soil profiles while Cu showed a relatively homogeneous profile distribution in the riparian soil. Soil organic matter (SOM), cation exchange capacity (CEC), and pH were identified to be the primary factors determining the distributions of Cd, Cu, Pb, and their chemical fractions, respectively, in the riparian soil with a high macroporosity. Nevertheless, soil porosity was the dominant factor (>65.0%) determining the distributions of all the three HMs and their fractions in the non-drainable micropore-dominated riparian soil Conclusions: Soil basic property and pore structure variations due to periodic hydrodynamic disturbances from reservoir operation are closely related to the redistribution of HMs in the riparian soil. The coupling of these two variations is strongly suggested to assist reliable evaluation of various contaminants, including but not limited to HMs, regarding their spatial redistributions and mobilization potentials in the vadose zone at larger scales in response to climate change. [ABSTRACT FROM AUTHOR]

A new multifunctional β-cyclodextrin-sodium xanthogenate (β-CDX) was successfully synthesized by a one-step process and applied to remove Pb(II) from aqueous solutions. The characteristics and chelation mechanisms of β-CDX were investigated by Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy, and the influences of various operating parameters such as pH (lime dosage), the order of the additions, β-CDX dosage, and the initial concentration of Pb(II) on the removal capacity of β-CDX and the characteristics of the products were systematically evaluated. The results demonstrated that the optimal removal effect for Pb(II) was achieved when β-CDX was used rather than using lime alone. In addition, it was more effective to add β-CDX to the working solutions prior to adding the lime than adding β-CDX after the lime. The use of 0.05 g/L of β-CDX was effective for the removal of Pb(II) according to the residual concentration when the initial concentration was 100 mg/L at different pH values. The maximum removal rate of the Pb(II) ions was 98% for all initial concentrations and the products were larger (size = 137.9 μm) and looser (Df = 1.73) at an optimum pH range from 9 to 12. The characterization results confirmed that the RC(S)SNa in the β-CDX was the main contributor to the chelation of the Pb(II). These properties of β-CDX make it a promising compound for the treatment of wastewater contaminated by hazardous metal ions. [ABSTRACT FROM AUTHOR]

In integrated circuit-grade single silicon Czochralski growth, the position and material of heat shield are main parameters affecting the heat exchange and crystal growth condition. By optimizing the above parameters, we attempted to increase the growth rate and crystal quality. Numerical simulation proved to verify the results before and after optimization. Through analyses of the temperature and microdefect distribution, it is found that the optimized heat shield can further increase the pulling rate and decrease the melt/crystal interface deflection, increase the average velocity of argon flow from ∼2 to ∼5 m·s, which is in favor of the transportation of SiO, and obtain the low defects concentration crystal and that the average temperature along the melt-free surface is 8 °C higher than before avoiding supercooled melt effectively. [ABSTRACT FROM AUTHOR]

In magnetic Czochralski (MCZ) silicon growth, the distance and diameter of the electrified coils may affect the magnetic field intensity and melt flow. By changing the above parameters, the optimum geometric configuration of the coils was attempted. Through analyses of the oxygen concentration distribution of the crystal/melt interface, axial and radial velocity distribution of melt and the magnetic field intensity in the melt, it is found that smaller diameter of coils contributes to reducing the needed current intensity and production costs. For a given current intensity, there is a best distance of coils when the oxygen concentration at crystal/melt interface reaches the lowest. [ABSTRACT FROM AUTHOR]