Influence of annealing pretreatment in different atmospheres on crystallization quality and UV photosensitivity of gallium oxide films.

Due to their high wavelength selectivity and strong anti-interference capability, solar-blind UV photodetectors hold broad and important application prospects in fields like flame detection, missile warnings, and secure communication. Research on solar-blind UV detectors for amorphous Ga2O3 is still in its early stages. The presence of intrinsic defects related to oxygen vacancies significantly affects the photodetection performance of amorphous Ga2O3 materials. This paper focuses on growing high quality amorphous Ga2O3 films on silicon substrates through atomic layer deposition. The study investigates the impact of annealing atmospheres on Ga2O3 films and designs a blind UV detector for Ga2O3. Characterization techniques including atomic force microscopy (AFM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) are used for Ga2O3 film analysis. Ga2O3 films exhibit a clear transition from amorphous to polycrystalline after annealing, accompanied by a decrease in oxygen vacancy concentration from 21.26% to 6.54%. As a result, the response time of the annealed detector reduces from 9.32 s to 0.47 s at an external bias of 10 V. This work demonstrates that an appropriate annealing process can yield high-quality Ga2O3 films, and holds potential for advancing high-performance solar blind photodetector (SBPD) development.

Effect of bacillus subtilis strain Z15 secondary metabolites on immune function in mice.

BACKGROUND: Previous studies have shown that secondary metabolites of Bacillus subtilis strain Z15 (BS-Z15) are effective in treating fungal infections in mice. To evaluate whether it also modulates immune function in mice to exert antifungal effects, we investigated the effect of BS-Z15 secondary metabolites on both the innate and adaptive immune functions of mice, and explored its molecular mechanism through blood transcriptome analysis. RESULTS: The study showed that BS-Z15 secondary metabolites increased the number of monocytes and platelets in the blood, improved natural killer (NK) cell activity and phagocytosis of monocytes-macrophages, increased the conversion rate of lymphocytes in the spleen, the number of T lymphocytes and the antibody production capacity of mice, and increased the levels of Interferon gamma (IFN-γ), Interleukin-6 (IL-6), Immunoglobulin G (IgG) and Immunoglobulin M (IgM) in plasma. The blood transcriptome analysis revealed 608 differentially expressed genes following treatment with BS-Z15 secondary metabolites, all of which were significantly enriched in the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) terms for immune-related entries and pathways such as Tumor Necrosis Factor (TNF) and Toll-like receptor (TLR) signaling pathways, and upregulated expression levels of immune-related genes such as Complement 1q B chain (C1qb), Complement 4B (C4b), Tetracyclin Resistant (TCR) and Regulatory Factor X, 5 (RFX5). CONCLUSIONS: BS-Z15 secondary metabolites were shown to enhance innate and adaptive immune function in mice, laying a theoretical foundation for its development and application in the field of immunity.

Effects of Bacillus subtilis BS-Z15 on Intestinal Microbiota Structure and Body Weight Gain in Mice.

In our previous study, we identified a metabolite of Bacillus subtilis BS-Z15 (a strain with probiotic characteristics) that could improve immunity in mice. In the present study, we examined the effects of B. subtilis BS-Z15 and its metabolites on body weight gain and the intestinal microbiota of mice. Sixty 25-day-old male Kunming white mice were selected and randomly divided into four groups: control group (A), daily saline gavage; B. subtilis-treated group (B), single gavage (1 × 109 CFU/time/animal/day); group D, 14 consecutive gavages (1 × 109 CFU/time/animal/day); and B. subtilis metabolite-treated group (E), 30 consecutive gavages (90 mg kg-1/time/animal/day). High-throughput sequencing technology was used to analyze intergroup differences in the mouse intestinal microbiota. The results showed that the three treated groups had significantly slower body weight gain compared with the control group, which lasted until the 45 days (P < 0.05), and the daily food intake of the treated mice was higher (P < 0.05). The intestinal microbiota structure of the mice in the treated groups was significantly altered compared with that in the control group, suggesting that B. subtilis BS-Z15 may regulate the weight gain of animals by affecting their intestinal bacterial composition. After stopping the gavage of B. subtilis BS-Z15, the abundance of this strain in the small intestine of the mice gradually decreased and its presence was undetectable at 45 days, indicating that B. subtilis BS-Z15 could not colonize the intestine of these mice. These findings suggest that B. subtilis BS-Z15 may regulate intestinal microbiota through its metabolites to reduce weight gain.