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In response to the complex working conditions and poor driving stability of high-clearance self-propelled sprayers, a nonlinear model of the chassis power system was established based on the independently controllable torque of each wheel of the developed electric sprayer. A layered-architecture chassis drive control strategy was formulated, and a stability control framework comprising an instability judgment module, an upper controller, and a lower controller was constructed based on the analysis of the impact of the centroid slip angle, the yaw rate, and the wheel slip rate on driving stability. An ideal reference model was established based on the seven-degree-of-freedom model of the sprayer, and the current state of the sprayer body was determined using the instability judgment module. A drive anti-slip controller and a yaw moment controller based on fuzzy PID theory and sliding mode control theory were designed. Additionally, an optimal torque distribution algorithm was developed based on tire characteristics to rationally allocate drive torque to each wheel, ensuring the stability of the sprayer during operation. Simulation tests were conducted using MATLAB/Simulink to evaluate the sprayer under four different driving conditions during transport and field operations. The test results showed that the "SMC + optimal distribution" control method in the chassis stability control strategy reduced the maximum deviations of the yaw rate and centroid slip angle by an average of 89.5% and 13.6%, respectively, compared to no control. The wheel slip rate during straight driving was well maintained at around 15%, enhancing the driving stability of the sprayer. [ABSTRACT FROM AUTHOR]

To explore the regulatory mechanism of endogenous hormones in the synthesis of anthocyanins in Anoectochilus roxburghii (Wall.) Lindl (A. roxburghii) under different light intensities, this study used metabolomics and transcriptomics techniques to identify the key genes and transcription factors involved in anthocyanin biosynthesis. We also analyzed the changes in and correlations between plant endogenous hormones and anthocyanin metabolites under different light intensities. The results indicate that light intensity significantly affects the levels of anthocyanin glycosides and endogenous hormones in leaves. A total of 38 anthocyanin-related differential metabolites were identified. Under 75% light transmittance (T3 treatment), the leaves exhibited the highest anthocyanin content and differentially expressed genes such as chalcone synthase (CHS), flavonol synthase (FLS), and flavonoid 3′-monooxygenase (F3′H) exhibited the highest expression levels. Additionally, 13 transcription factors were found to have regulatory relationships with 7 enzyme genes, with 11 possessing cis-elements responsive to plant hormones. The expression of six genes and two transcription factors was validated using qRT-PCR, with the results agreeing with those obtained using RNA sequencing. This study revealed that by modulating endogenous hormones and transcription factors, light intensity plays a pivotal role in regulating anthocyanin glycoside synthesis in A. roxburghii leaves. These findings provide insights into the molecular mechanisms underlying light-induced changes in leaf coloration and contribute to our knowledge of plant secondary metabolite regulation caused by environmental factors. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of the present study was to investigate the expressions of DNA methyltransferase 1 (DNMT1) and cyclin A1 (CCNA1) protein and mRNA in the process of cervical carcinogenesis., Methods: The specimens were separated into the following groups: control (n=30), low-grade squamous intraepithelial lesions (LSIL, n=30), high-grade squamous intraepithelial lesions (HSIL) and squamous cell cervical cancers (SCC, n=30). Immunohistochemical examination, Western blot and real-time quantitative PCR were used to investigate the protein and mRNA expressions of DNMT1 and CCNA1 in cervical tissues., Results: We found that the positive expression rate and intensity of DNMT1 mRNA and protein gradually increased in the process of cervical carcinogenesis. However, the increase of the positive expression rate of DNMT1 mRNA and protein form the LSIL group to HSIL group was not significant ( P >0.05). After cervical intraepithelial neoplasia (CIN), the positive expression rate and intensity of CCNA1 mRNA and protein significantly decreased with the aggravation of cervical lesions ( P <0.05), and there was no significant difference between the LSIL and control groups ( P >0.05)., Conclusions: With the severity of cervical lesions, the expression of DNMT1 protein and mRNA increased gradually. The expression of CCNA1 protein and mRNA decreased gradually. The DNMT1 and CCNA1 expressions are associated with cervical lesions., Competing Interests: None., (IJCEP Copyright © 2019.)