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This work aims to investigate the cultural and psychological factors that significantly affect teachers' intention to accept VR technology and use it long-term in their classes in elementary and secondary schools. The extended unified theory of acceptance and use of technology (UTAUT2) model effectively measured such factors in this context. We conducted a questionnaire survey with 351 elementary and secondary school teachers in four provinces in China and analyzed their responses utilizing Partial Least Squares (PLS) technique. The results of this work showed that performance expectancy, effort expectancy, social influence, facilitating conditions, and hedonic motivation significantly impacted continued usage intention. However, the habit did not promote continued usage intention. Based on the results, research on VR classroom application guidance and teachers' professional development with VR technology applications should be strengthened. Meanwhile, increasing the publicity of integrating VR technology into classroom teaching, creating a favorable climate for VR technology adoption, and enhancing the fun of VR technology can also contribute to teachers' continued VR technology usage intention in classroom teaching. [ABSTRACT FROM AUTHOR]

The startup process of pump as turbine (PAT) is actually unavoidable. In order to reveal the transient behavior of a small centrifugal pump reversing as a turbine during an atypical startup, transient experiments are carried out on PAT test rig in the case of two valve openings and four rotational speeds so as to obtain the evolution characteristic of the external performance parameters over time. Meanwhile, three dimensionless parameters are also employed to deeply reveal the transient characteristics. It is found that the shock phenomena in static pressure are prevalent at the outlet of PAT, and that it tends to lag and weaken with increasing stable rotational speed. All three dimensionless factors have maximum values at the initial stage of PAT startup, whereafter they demonstrate the different evolution characteristics. [ABSTRACT FROM AUTHOR]

The transient startup and shutdown of centrifugal pumps is inevitable and its transient performance has thus attracted increasing attention in recent years. This study aims to reveal the transient characteristics of centrifugal pumps during the start-stop process by using the dimensionless analysis method and quasi-steady-state method. The research objects are three typical centrifugal pumps with an impeller structure. The startup process includes quick and slow startup, and the shutdown process includes low-speed and high-speed idle rotation. Results show that the similarity law of centrifugal pumps can be applied to transient hydraulic performance prediction under full flow conditions during slow startup and under small flow conditions during quick startup and idle shutdown. Quick or slow startup does not affect the evolution of the dimensionless power coefficients. The research result may be useful for the design of the new fluidmachinery equipment by utilizing transient hydraulic performance. [ABSTRACT FROM AUTHOR]

Objectives: Osteoarthritis (OA) is a chronic joint disease characterized by osteoproliferation and the degeneration and destruction of articular cartilage. Platelet-rich plasma (PRP) is rich in various growth factors that have been reported to promote bone defect repair. This study examined the specific role and mechanism of PRP in OA. Methods: OA model cells were created by treating articular chondrocytes with IL-1β. After treatment of the model cells with PRP or/and a T-box transcription factor 3 (TBX3)-overexpression plasmid, TBX3 expression was monitored via RT-qPCR, western blotting, and immunofluorescence assays. IL-1β, IL-33, and Caspase-3 levels were detected with ELISA kits. Levels of NLRP3, Caspase-1, MMP9, MMP13, and COL2A1 expression were evaluated by western blotting, and cell proliferation was assessed by the CCK-8 assay. Results: Our results showed that TBX3 expression was upregulated in IL-1β-induced articular chondrocytes. IL-1β stimulation induced inflammation and the production of matrix metalloproteinases, activated Caspase-3 and the NLRP3/Caspase-1 pathway, inhibited the proliferation of articular chondrocytes; however, all those affects mediated by IL-1β could be markedly reversed by PRP. We also found that PRP alleviated IL-1β-induced inflammation, apoptosis, and extracellular matrix degradation in articular chondrocytes by inhibiting TBX3. Our findings suggest that PRP alleviates OA progression in vitro by downregulating TBX3. Conclusion: PRP suppressed OA progression in vitro by inhibiting TBX3, which may be its mechanism of action in treating OA. [ABSTRACT FROM AUTHOR]

Objectives: Osteoarthritis (OA) is a chronic joint disease characterized by osteoproliferation and the degeneration and destruction of articular cartilage. Platelet-rich plasma (PRP) is rich in various growth factors that have been reported to promote bone defect repair. This study examined the specific role and mechanism of PRP in OA. Methods: OA model cells were created by treating articular chondrocytes with IL-1β. After treatment of the model cells with PRP or/and a T-box transcription factor 3 (TBX3)-overexpression plasmid, TBX3 expression was monitored via RTqPCR, western blotting, and immunofluorescence assays. IL-1β, IL-33, and Caspase-3 levels were detected with ELISA kits. Levels of NLRP3, Caspase-1, MMP9, MMP13, and COL2A1 expression were evaluated by western blotting, and cell proliferation was assessed by the CCK-8 assay. Results: Our results showed that TBX3 expression was upregulated in IL-1β-induced articular chondrocytes. IL-1β stimulation induced inflammation and the production of matrix metalloproteinases, activated Caspase-3 and the NLRP3/Caspase-1 pathway, inhibited the proliferation of articular chondrocytes; however, all those affects mediated by IL-1β could be markedly reversed by PRP. We also found that PRP alleviated IL-1β-induced inflammation, apoptosis, and extracellular matrix degradation in articular chondrocytes by inhibiting TBX3. Our findings suggest that PRP alleviates OA progression in vitro by downregulating TBX3. Conclusion: PRP suppressedOA progression in vitro by inhibiting TBX3, which may be its mechanism of action in treating OA. [ABSTRACT FROM AUTHOR]