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In this work, single-crystal gallium oxide (β-Ga2O3 ) thin films were epitaxially grown on different off-cut angled c-plane sapphire substrates by metal organic chemical vapor deposition (MOCVD), and the effect of off-cut angles on the crystal quality and surface roughness of the epitaxial films were investigated. For the β-Ga2O3 epilayer grown on the 6° off-cut angled sapphire substrate, the full width at half maximum (FWHM) of the rocking curve is reduced to be 1.10°, together with the smallest surface roughness of 7.7 nm. Consequently, the metal-semiconductor-metal structured solar-blind ultraviolet photodetectors were fabricated by lithography, development, electron beam evaporation and lift-off techniques. The photodetector has excellent performances, including photo-dark current ratio of 6. 2 × 106, peak photoresponsivity of 87. 12 A/ W at 248 nm, specific detectivity of 3. 5 ×1015 Jones, UV-visible rejection ratio of 2. 36 ×104, and total response time of 226. 2 μs. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mesenchymal stem cell transplantation has been proved to be effective for ulcerative colitis, while the effect of endothelial progenitor cells in ulcerative colitis treatment is still unknown. They are both promising cells for tissue engineering, which can be used for cell transplantation. OBJECTIVE: To explore whether co-transplantation of endothelial progenitor cells and adipose mesenchymal stem cells can relieve ulcerative colitis in a mouse model. METHODS: C57BL/6J mice were randomly divided into six groups (n=24 per group): co-transplantation group, mesenchymal stem cell transplantation group, endothelial progenitor cell transplantation group, glucocorticoid treatment group, transplantation control group and normal control group. Murine ulcerative colitis model was established in all groups except for the normal control group. At 7 and 10 days after modeling, transplantation groups were respectively injected via tail vein with adipose mesenchymal stem cells and/or endothelial progenitor cells, glucocorticoid or PBS. Mice were sacrificed at 12 days after modeling. Colon length, disease activity index, histological score and the serum level of tumor necrosis factor-α were compared between groups. RESULTS AND CONCLUSION: Treatment with glucocorticoid was significantly effective for ulcerative colitis relative to the transplantation control group (P < 0.05). Adipose mesenchymal stem cells were proved to have better effects than glucocorticoids in the murine ulcerative colitis model (P < 0.05). No significant differences were found between endothelial progenitor cell transplantation group and transplantation control group (P > 0.05). Co-transplantation of adipose mesenchymal stem cells and endothelial progenitor cells was better than the other treatments, which significantly improved the shortening of the colon, disease activity index, histological score, and serum level of tumor necrosis factor-α. [ABSTRACT FROM AUTHOR]