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This study explores the surface characteristics evaluation and performance optimization of tungsten (W)-doped vanadium dioxide (VO2) thin films. W-doped vanadium dioxide films were deposited on B270 glass substrates using an electron beam evaporation technique combined with the ion beam-assisted deposition (IAD) method. The Taguchi method was used to analyze the performance optimization of VO2 thin films, and L16 orthogonal array design and Minitab software were used for optimization calculations. The surface roughness, visible light transmittance, infrared transmittance, and residual stress of un-doped and tungsten-doped (3–5%) VO2 thin films are set as the quality performance indicators of thin films. The goal is to identify the key factors that affect the performance of VO2 thin films during deposition and optimize their process parameters. The experimental results showed that a VO2 thin film with 3% tungsten doping, an oxygen flow rate of 60 sccm, a heating temperature of 280 °C, and a film thickness of 60 nm exhibited the lowest surface roughness of 2.12 nm. A VO2 thin film with 5% tungsten doping, an oxygen flow rate of 0 sccm, a heating temperature of 280 °C, and a film thickness of 60 nm had the highest visible light transmittance at 64.33%. When the oxygen flow rate was 60 sccm, the heating temperature was 295 °C, the film thickness was 150 nm, and the tungsten doping was 5%, the VO2 thin film showed the lowest infrared transmittance of 31.34%. A thin film with 5% tungsten doping, an oxygen flow rate of 20 sccm, a heating temperature of 265 °C, and a film thickness of 120 nm exhibited the lowest residual stress of −0.195 GPa. [ABSTRACT FROM AUTHOR]

This study aims to investigate the thermomechanical properties of vanadium dioxide (VO2) thin films. A VO2 thin film was simultaneously deposited on B270 and H-K9L glass substrates by electron-beam evaporation with ion-assisted deposition. Based on optical interferometric methods, the thermal–mechanical behavior of and thermal stresses in VO2 films can be determined. An improved Twyman–Green interferometer was used to measure the temperature-dependent residual stress variations of VO2 thin films at different temperatures. This study found that the substrate has a great impact on thermal stress, which is mainly caused by the mismatch in the coefficient of thermal expansion (CTE) of the film and the substrate. By using the dual-substrate method, thermal stresses in VO2 thin films from room temperature to 120 °C can be evaluated. The thermal expansion coefficient is 3.21 × 10−5 °C−1, and the biaxial modulus is 517 GPa. [ABSTRACT FROM AUTHOR]

The undoped and tungsten (W)-doped vanadium dioxide (VO2) thin films were prepared by electron beam evaporation associated with ion-beam-assisted deposition (IAD). The influence of different W-doped contents (3–5%) on the electrical, optical, structural, and thermo-mechanical properties of VO2 thin films was investigated experimentally. Spectral transmittance results showed that with the increase in W-doped contents, the transmittance in the visible light range (400–750 nm) decreases from 60.2% to 53.9%, and the transmittance in the infrared wavelength range (2.5 μm to 5.5 μm) drops from 55.8% to 15.4%. As the W-doped content increases, the residual stress in the VO2 thin film decreases from −0.276 GPa to −0.238 GPa, but the surface roughness increases. For temperature-dependent spectroscopic measurements, heating the VO2 thin films from 30 °C to 100 °C showed the most significant change in transmittance for the 5% W-doped VO2 thin film. When the heating temperature exceeds 55 °C, the optical transmittance drops significantly, and the visible light transmittance drops by about 11%. Finally, X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to evaluate the microstructure characteristics of VO2 thin films. [ABSTRACT FROM AUTHOR]

Abstract: Background: MicroRNAs (miRNAs) play crucial roles in head and neck squamous cell carcinoma (HNSCC). This study investigates whether miR‐31, miR‐96, and miR‐182 are involved in targeting Numb during HNSCC. Methods: The expression of miR‐31/96/182 in tumor tissues was analyzed. Reporter assay, knockdown, expression, and oncogenic analysis were carried out in cell lines. Results: Upregulation of miR‐31/96/182 was detected in tumor tissues. In addition, advanced tumors showed higher expression levels of these miRNAs. The expression of these miRNAs was upregulated after treatment with areca ingredients (P < .01 or P < .001). These miRNAs directly targeted the 3′ untranslated region (UTR) sequence of the Numb gene. An increased migration and invasion of HNSCC cells was associated with the exogenous expression of miR‐31/96/182 (P < .01 or P < .001), and this was reverted by expression of Numb. Conclusion: This study provides new evidence demonstrating that there is frequent and concordant upregulation of miR‐31, miR‐96, and miR‐182 during HNSCC and these miRNAs co‐target Numb. [ABSTRACT FROM AUTHOR]

This study presents a multilayer design and fabrication of an optical notch filter for enhancing visual quality. A cost-effective multilayer design of notch filter with low surface roughness and low residual stress is proposed. A 9-layer notch filter composed of SiO2 and Nb2O5 with a central wavelength of 480 nm is prepared by electron beam evaporation combined with ion-assisted deposition. The optical transmittance, residual stress, and surface morphology are measured by a UV/VIS/NIR spectrophotometer, Twyman-Green interferometer and field emission scanning electron microscopy (FE-SEM). The transmittance of the notch filter at the central wavelength is above 15%, and the average transmittance of the transmission band is about 80%. The residual stress of the notch filter is −0.235 GPa, and the root mean square surface roughness is 1.85 nm. For improving the visual quality, a good image contrast can be obtained by observing the microscopic image using the proposed notch filter. [ABSTRACT FROM AUTHOR]

Background/aim: Immunotherapy has been considered a promising approach for brain tumor treatment since the discovery of the brain lymphatic system. Glioblastoma (GBM), the most aggressive type of brain tumor, is associated with poor prognosis and a lack of effective treatment options., Materials and Methods: To test the efficacy of human anti-PD-1, we used a humanized PD-1 knock-in mouse to establish an orthotopic GBM-bearing model., Results: Nivolumab, a human anti-PD-1, effectively inhibited tumor growth, increased the survival rate of mice, enhanced the accumulation and function of cytotoxic T cells, reduced the accumulation and function of immunosuppressive cells and their related factors, and did not induce tissue damage or biochemical changes. The treatment also induced the accumulation and activation of CD8 + cytotoxic T cells, while reducing the accumulation and activation of myeloid-derived suppressor cells, regulatory T cells, and tumor-associated macrophages in the immune microenvironment., Conclusion: Nivolumab has the potential to be a treatment for GBM., (Copyright © 2023, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)