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Neutrophil extracellular traps (NETs) are produced by neutrophil activation and usually have both anti-infective and pro-damage effects. Streptococcus uberis (S. uberis), one of the common causative organisms of mastitis, can lead to the production of NETs. Taurine, a free amino acid abundant in the organism, has been shown to have immunomodulatory effects. In this study, we investigated the molecular mechanisms of S. uberis-induced NETs formation and the regulatory role of taurine. The results showed that NETs had a disruptive effect on mammary epithelial cells and barriers, but do not significantly inhibit the proliferation of S. uberis. S. uberis induced NADPH oxidasedependent NETs. TLR2-mediated activation of the MAPK signaling pathway was involved in this process. Taurine could inhibit the activation of MAPK signaling pathway and NADPH oxidase by modulating the activity of TAK1, thereby inhibiting the production of ROS and NETs. The effects of taurine on NADPH oxidase and NETs in S. uberis infection were also demonstrated in vivo. These results suggest that taurine can protect mammary epithelial cells and barriers from damage by reducing S. uberis-induced NETs. These data provide new insights and strategies for the prevention and control of mastitis. [ABSTRACT FROM AUTHOR]

College students'motivation and engagement are regarded as essential factors to promote their academic development and wellbeing. However, motivation and engagement among college students appear to decline after they enter the university. Guided by the framework of self-determination theory, this study attempted to explore a motivational model of how three dimensions of perceived teacher support (autonomy, structure, and involvement) related to student motivation and class engagement, using need satisfaction as a mediator. Drew on a survey of the perceptions of 705 Chinese university students, the results showed that besides structure, both autonomy support and involvement positively related to students' need satisfaction. Further, need satisfaction was positively associated with autonomous motivation, controlled motivation, and class engagement and negatively linked with amotivation. Yet, only autonomous motivation was positively predicted for class engagement. Need satisfaction and the chain from need satisfaction to autonomous motivation were found to be the significant mediators. The practical implications of educational practices are discussed. [ABSTRACT FROM AUTHOR]

This study is concerned with the sliding mode control design subject to actuator saturation. The actuator saturation is formulated with the rate limitation and the standard magnitude limitation. Both the saturated sliding mode control approaches against the known and the unknown bounded uncertainties are discussed. The stability analysis for the resulting overall closed-loop systems is conducted. Moreover, several optimisation conditions are established to estimate the attraction domain of the saturated system under the designed controllers, by determining the invariant set of the system. Finally, simulation examples are shown to illustrate the proposed control design scheme. [ABSTRACT FROM AUTHOR]