Conspectus Laser diodes (LDs), free of “efficiency droop”, can bear a superhigh power density. Laser-driven white light sources (blue LD + laser phosphors), which promise super brightness and high directionality, have emerged for various applications, including lighting, displays, communications, and endoscopy. Laser phosphors are critical components of this technology, which determine the luminous efficacy, luminance, and color quality of the device. However, most phosphors suffer from serious luminance saturation when excited by a high-power-density blue laser. The synergetic effect of thermal quenching and photoexcitation quenching causes the luminance saturation, named thermally and optically induced luminance saturation, respectively. To avoid luminance saturation, laser phosphors should have the following merits to withstand a high-power-density laser excitation: (i) high internal quantum efficiency; (ii) small Stokes shift; (iii) low thermal quenching; (iv) high thermal conductivity; (v) short decay time. Robust inorganic phosphor bulks have been developed for laser excitation. Among them, phosphor ceramics are the best choice for high-power-density laser excitation owing to their excellent reliability and rich microstructure tunability, and phosphor films act as a complementary component to realize flexible color tuning with low fabrication cost. Moreover, property evaluation methods for LED phosphors are not all suitable for laser phosphors, as the light conversion process occurs only within a small light spot area. First, the color-conversion process in laser-driven lighting occurs at a small interface between the excitation blue laser and the phosphor, and the output luminous flux is collected from either the transmissive or the reflective side for practical applications. Therefore, when evaluating the luminous flux of a laser phosphor, the sample should be placed at the entrance or exit of the integrating sphere rather than in the center of the integrating sphere as in LED lighting. Second, the incident blue laser spot tends to broaden during the color-conversion process. Comparison of the incident laser spot with the real light spot provides a descriptor to evaluate the light confinement ability of the laser phosphor. The real light spot area is also a key parameter for calculating the luminance of the light source. Therefore, the precise measurement of the light spot area is very important, but most researches have ignored it. Third, the excitation blue light is highly collimated with a Gaussian-distributed energy, whereas the phosphor-converted yellow light energy follows a Lambertian distribution. This intrinsic difference leads to uneven mixing of blue and yellow light, and the light uniformity of laser-driven white light sources must be measured to evaluate the color quality. Furthermore, this account also proposes future research priorities of discovering high-performance red-emitting laser phosphors and extending the applications to communications. This Account will promote scientific and tech...
Background. Xiezhuo Huayu Yiqi Tongluo Formula (XHYTF) consists of 14 Chinese herbal medicines. In this study, we investigated the potential mechanism of XHYTF in the treatment of uric acid nephropathy (UAN) through network pharmacology, molecular docking, and in vivo methods. Methods. Using various pharmacological databases and analysis platforms, information on the active ingredients and targets of Chinese herbal medicine was collected, and UAN disease targets were retrieved using OMIM, Gene Cards, and NCBI. Then common target proteins were integrated. A Drug-Component-Target (D-C-T) map was constructed to screen core compounds and build a protein-protein interaction (PPI) network. Further, Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed for common targets, and a Drug-Component-Target-Pathway (D-C-T-P) network diagram was constructed. The molecular docking simulation was performed to verify the binding affinity between core components and hub targets. Subsequently, the UAN rat model was established, followed by the collection of serum and renal tissues. The expression levels of indicators in the serum were determined using an enzyme-linked immunosorbent assay. The pathological changes of renal tissues were detected using H & E staining and Masson staining. The expression of related proteins in renal tissue was detected by western blot. Results. In the study, 216 active ingredients and 439 targets in XHYTF were screened, and 868 targets were identified as being related to UAN. Among them, 115 were common targets. Based on the D-C-T network, quercetin, luteolin, β-sitosterol, and stigmasterol were observed to be the key active ingredients of XHYTF that were effective against UAN. The analysis of the PPI network revealed TNF, IL6, AKT1, PPARG, and IL1β as the 5 key targets. GO enrichment analysis revealed that the pathways were mainly concentrated in cell killing, regulation of signaling receptor activity, and other activities. Subsequently, KEGG pathway analysis revealed that multiple signaling pathways, including the HIF-1, PI3K-Akt, IL-17, and other signaling pathways, were closely related to the action of XHYTF. All 5 key targets were confirmed to interact with all core active ingredients. In vivo experiments indicated that XHYTF significantly reduced blood uric acid and creatinine levels, alleviated inflammatory cell infiltration in kidney tissues, reduced the levels of serum inflammatory factors such as TNF-α and IL1β, and ameliorated renal fibrosis in rats with UAN. Finally, western blot revealed decreased levels of PI3K and AKT1 proteins in the kidney, which confirmed the hypothesis. Conclusion. Collectively, our observations demonstrated that XHYTF significantly protects kidney function, including alleviation of inflammation and renal fibrosis via multiple pathways. This study provided novel insights into the treatment of UAN using traditional Chinese medicines.
The timescale dependent relationships between the atmospheric electrical conductivity and concentrations of aerosol particles, carbon monoxide, sulfur dioxide, and nitrogen dioxide in downtown Toronto were examined by spectral analyses based on a year of hourly averaged observations at a single site during 1973–1974. The highlights of the relationships were found as follows: (1) The variance spectra (or power spectra) of both electrical conductivity and pollutant concentrations obeyed the −5/3 power law of spectral decay, suggesting that the air in the city of Toronto during the experiment was severely polluted. (2) The variation of the electrical conductivity corresponded significantly to those of pollutant concentrations for most timescales, characterized by a common variance‐contributing scale range from a few hours to a few weeks in the variance spectra. (3) The variations of both electrical conductivity and pollutant concentrations were contributed mainly by daily changes of hourly averaged values and weekly changes of daily averaged values, coinciding with the daily and weekly cycles in the city's traffic and industrial activities. (4) The electrical conductivity correlated negatively with pollutant concentrations for most timescales. However, the correlations were contributed mainly by weekly changes of daily averaged values, different from the variation contributions of these variables. This suggests that the electrical conductivity is poorly synchronized with pollutant concentrations for the timescales smaller than diurnal component, which could be expected to introduce noises if the correlations between the electrical conductivity and pollutant concentrations at the scales smaller than diurnal component are pursued.
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