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g/C3N4-ZnO composite catalysts were synthesized through surface hybridization of the delocalized conjugated-π structure of g/C3N4 with the closely contacted surface of ZnO via a successive and simultaneous calcination procedure, and two kinds of photocatalysts, g/C3N4-ZnO1 and g/C3N4-ZnO2, were obtained. Heterojunctions were formed between the two components, which promote the separation of photogenerated carriers efficiently, and then enhanced the degradation of 100 mg/L of AMX The degradation rate of g/C3N4-ZnO1 was 1.54, 11.33, and 2.52-fold that of g/C3N4-ZnO2, g/C3N4 and ZnO, respectively, at a 3.5-h reaction period, with the dosage of 0.3 g/L, and solution pH at 7.0±0.2. The recycle and reuse ability was excellent and 90.5% of AMX mitigation was achieved in the fifth cycle. For g/C3N4-ZnO1, electrons migrated from the conduction band of g/C3N4 to that of ZnO via the heterojunction. ·OH and h+ were the main active species for AMX degradation, compared to ·O2− dominated for g/C3N4. Twelve intermediate products were identified, and two degradation pathways were inferred for g/C3N4-ZnO1 and g/C3N4-ZnO2, respectively. Finally, transformation products without lactam rings were achieved, which lost most of the antibacterial potencies, and the ecotoxicity was also dramatically decreased as indicated by the ECOSAR program. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to determine the relationship between the apparent diffusion coefficient (ADC) and lumbar intervertebral disc degeneration using diffusion-weighted magnetic resonance imaging (DWI). Materials and methods: Using a 3 T magnetic resonance scanner, DWI of the lumbar spine was assessed in 109 patients, with a total of 545 lumbar discs analyzed. Apparent diffusion coefficient values were recorded for each disc, and all discs were visually graded by two independent observers using Pfirrmann's grading system. Apparent diffusion coefficient values of disc were tested by correlation with qualitative clinical grading of degeneration severity, patient age, and sex. Correlations were investigated using Pearson's and Spearman's rank correlation analysis, and multiple regression analysis. Results: Intervertebral disc degeneration was negatively correlated with ADC values of all levels (Spearman's correlation coefficient ranged from −0.381 to −0.604, p < 0.001). There was a significant negative association between age and ADC values at all spinal levels (Pearson's correlation coefficient ranged from −0.353 to −0.650, p < 0.001). When stepwise regression models were analyzed, both disc degeneration and age remained negatively associated with ADC values at each lumbar level (standardized coefficients ranged from −0.231 to −0.505, p < 0.01 and standardized coefficients ranged from −0.179 to −0.523, p < 0.05 respectively). Conclusion: Apparent diffusion coefficient values obtained using DWI can assess lumbar intervertebral disc degeneration, and the ADC values were negatively correlated with the degree of disc degeneration. [ABSTRACT FROM AUTHOR]

The formation of optical planar waveguides in LiNbO3 and stoichiometric LiNbO3 crystals by proton exchange was reported. The prism-coupling method was used to characterize the dark-line spectroscopy at the wavelength of 633 and 1539 nm, respectively. The mode optical near-field outputs from proton-exchanged LiNbO3 and SLN waveguides at 633 nm were presented. The mode field from stoichiometric LiNbO3 (SLN) waveguide is lighter and more uniform than that from LiNbO3 waveguide, which means the quality of the waveguide in SLN crystal is better than that of the LiNbO3 waveguide. For proton-exchanged LiNbO3 waveguides, the evolution of the refractive index profile with annealing was presented. The disorder profiles of Nb atoms in proton-exchanged LiNbO3 waveguides were obtained by Rutherford backscattering/channeling technique. It is shown that the longer the exchange time, the larger the displacement of Nb atoms. [ABSTRACT FROM AUTHOR]