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Atmospheric pressure and zenith wet delay (ZWD) are essential for global navigation satellite system (GNSS) tropospheric correction and precipitable water vapor (PWV) retrieval. As the development progresses of real-time GNSS kinematic technology, moving platforms, such as airborne and shipborne, require high-quality tropospheric delay information to pre-correct errors. Most existing tropospheric models are only applicable to the Earth's surface and exhibit poor accuracies in high-altitude areas due to simple vertical fitting functions and limited temporal resolution of the underlying parameters. Hence, an improved global empirical pressure and ZWD model is developed using 5-year ERA5 hourly reanalysis data, called IGPZWD, which takes seasonal and intraday variations into consideration. The vertical accuracy and applicability of IGPZWD model are further optimized by introducing the annual and semi-annual harmonics for pressure and ZWD height-scale factors of exponential function with three orders. Taking the ERA5 and radiosonde profile data in 2020 as reference, the pressure and ZWD of IGPZWD model show superior performance compared to those of three state-of-the-art models, i.e., GPT3, IGPT, and GTrop. Furthermore, IGPZWD-predicted zenith tropospheric delay (ZTD) yields improvements of up to 65.7 %, 2.4 %, and 7.8 % over that of GPT3, RGPT3, and GTrop models on a global scale, respectively. The proposed vertical correction algorithm effectively weakens the impact of accumulation error caused by excessive height difference, achieving optimal accuracy and feasibility in the high-altitude area. The IGPZWD model can be extensively applied in GNSS kinematic precision positioning, as well as atmospheric water vapor sounding. [ABSTRACT FROM AUTHOR]

With the rise of the metaverse, digital transformation is profoundly affecting the field of art exhibitions. Museums and galleries are actively adopting metaverse technologies to present artworks through virtual platforms, providing audiences with novel opportunities for immersive engagement and art experiences and shaping high-quality user experiences. However, the factors influencing user engagement in the metaverse art exhibition platform (MeAEP) remain unclear in the current research. This research combines the information systems success model (ISSM) and the hedonic motivation system adoption model (HMSAM) to construct a theoretical model that provides insights into the factors influencing MeAEP users' intention to engage and their immersion behavior, with a focus on the sustainability of the art exhibition. We quantitatively analyzed 370 users that experienced MeAEP and analyzed the data and measurement model using SPSS 27 and partial least squares structural equation modeling (PLS-SEM). The results showed that information quality (IQ), system quality (SQ), and perceived ease of use (PEOU) significantly and positively influenced perceived usefulness (PU), curiosity (CUR), joy (JOY), and control (CON). PU, JOY, and CON have a positive and significant effect on Immersion (IM). Finally, PU, CUR, JOY, and CON had a positive effect on behavioral intention (BI). In conclusion, only one of the twenty hypotheses was not supported. The research findings not only enrich the academic and managerial theories related to the metaverse and art exhibition platforms, but also provide practical insights for administrators, developers, and MeAEP designers to create higher-quality and more immersive art content, as well as provide constructive ideas for the sustainability of art exhibitions to further enhance user experience. [ABSTRACT FROM AUTHOR]

Atmospheric pressure and Zenith wet delay (ZWD) are essential for GNSS tropospheric correction and precipitable water vapor (PWV) retrieval. As the development progresses of real-time GNSS kinematic technology, moving platforms such as airborne and shipborne require high-quality tropospheric delay information to pre-correct errors. Most existing tropospheric models are only applicable to the Earth surface, while exhibiting poor accuracies in high-altitude areas due to simple vertical fitting functions and limited temporal resolution of the underlying parameters. Hence, an improved global empirical pressure and ZWD model is developed using 5-years ERA5 hourly reanalysis data, called IGPZWD, which takes seasonal and intraday variations into consideration. The vertical accuracy and applicability of IGPZWD model are further optimized by introducing the annual and semi-annual harmonics for pressure and ZWD height scale factors of exponential function with three orders. Taking the ERA5 and radiosonde profiles data in 2020 as reference, the pressure and ZWD of IGPZWD model show superior performance than those of three state-of-the-art models, i.e., GPT3, IGPT and GTrop. Furthermore, IGPZWD-predicted ZTD yields improvements of up to 65.7 %, 2.4 % and 7.8 % over that of GPT3, RGPT3 and GTrop models on a global scale respectively. The proposed vertical correction algorithm effectively weakens the impact of accumulation error caused by excessive height difference, achieving optimal accuracy and feasibility in the high-altitude area. The IGPZWD model can be extensively applied in GNSS kinematic precision positioning as well as atmospheric water vapor sounding. [ABSTRACT FROM AUTHOR]

Objectives: The aim of our study was to determine the impact of Th17/Treg imbalance on the progression and malignant transformation of oral submucosal fibrosis (OSF). Materials and Methods: To assess Th17 and Treg expression, overall 52 peripheral blood samples from OSF, oral squamous cell carcinoma (OSCC) patients, and healthy donors were analyzed by flow cytometry. Thirty normal oral mucosa, 72 OSF, and 90 OSCC samples were analyzed by immunohistochemistry. Results: In peripheral blood samples, in OSCC with OSF, Th17 and Treg expression were significantly higher than those in OSF and OSCC without OSF as confirmed by immunohistochemistry. During OSF progression, Th17 and Th17/Treg ratio showed an increasing trend, while Treg expression showed a decreasing trend. Treg expression was significantly higher in OSCC with OSF than in OSF and OSCC without OSF, whereas the Th17/Treg ratio was significantly lower in OSCC with OSF. Treg expression was significantly correlated with smoking and clinical stage. Th17/Treg ratio was significantly associated with tumor size, lymph node metastasis, and clinical stage. A low Th17/Treg ratio was significantly associated with poor prognosis. Conclusions: Th17/Treg ratio is a potential diagnostic indicator for OSF occurrence and malignant transformation and was an independent prognostic factor for OSCC. [ABSTRACT FROM AUTHOR]

Objective: To evaluate and analyze the clinical effect of CBCT imaging technology on the restoration of upper anterior teeth of the elderly., Methods: 36 elderly patients with upper anterior teeth loss in our hospital from January 2018 to January 2020 were selected for implant restoration. Patients were equally randomized into a curved tomographic restoration group (TR group) and a CBCT restoration group (CR group). Patients in the two groups underwent traditional implant restoration. Then we compared and analyzed the implant migration, the adjustment time of first wearing, and the success rate of axial gingival recession and restoration satisfaction of patients in the two groups., Results: The neck offset and the root offset of the implants in the CR group was (0.77±0.15) mm and (0.83±0.17) mm, respectively, which were significantly lower than (1.25±0.27) mm and (1.73±0.29) mm in the TR group (t=6.593, t=11.359, all P<0.01). The initial wearing adjustment time of patients in the CR group [(8.73±1.94) min] was significantly less than (18.79±4.85) min in the TR group (t=8.171, P<0.01); the CR group had a significantly higher success rate of axial gingival recession as compared to the CR group (94.44% vs 61.11%, χ 2 =6.0857, P<0.05); The restoration satisfaction rate of patients in the CR group was 100%, which was significantly higher than 77.78% of the TR group (χ 2 =8.7429, P<0.05)., Conclusion: The CBCT imaging technology has a significant clinical effect on the restoration of the upper anterior teeth of the elderly, which effectively reduces the deviation of implant placement, shorten the adjustment time of their initial wearing, and greatly improves the success rate of axial gingival recession, effectively guarantees the long-term stability and aesthetics of dental implant restoration, and significantly enhances the satisfaction of patients., Competing Interests: None., (AJTR Copyright © 2021.)