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Pimpinellin is a phenylpropanoid compound involved in various physiological and pathological processes in the body. The specific impact of pimpinellin on ulcerative colitis (UC) remains uncertain. Research on pimpinellin by using a dextran sulfate sodium (DSS)-induced UC model can lay the groundwork for future drug screening and various treatment approaches for UC. This research focused on investigating the effects and mechanisms of pimpinellin on DSS-induced UC in mice. The findings indicated that pimpinellin mitigated DSS-induced shortening of the colon and intestinal barrier damage and notably lowered inflammatory cytokine levels. Mechanistic analysis revealed that pimpinellin boosted the protein expression of intestinal barrier proteins by inhibiting the MAPK/NF-κB signaling pathway. Additionally, pimpinellin enhanced the levels of beneficial gut probiotics (S24–7 and Lactobacillaceae) while reducing the presence of harmful bacteria (Enterobacteriaceae). Further studies indicated that administering 100 mg/kg pimpinellin could significantly alleviate UC by modulating the gut microbiota. In summary, timely use of pimpinellin can alleviate DSS-induced UC by reducing inflammation, maintaining intestinal barrier integrity, and adjusting gut microbiota. This research broadens the potential pharmaceutical applications of pimpinellin. Pimpinellin effectively alleviates ulcerative colitis (UC) symptoms by protecting the mucosal barrier, inhibiting the MAPK/NF-κB inflammatory pathways, and enhancing the abundance of anti-inflammatory gut microbiota. [Display omitted] [ABSTRACT FROM AUTHOR]

The drag coefficient of particles is an important parameter for predicting the transport properties of particle-laden flows. For a sphere immersed in continuum flows, the drag coefficient is typically related to the Reynolds number (Re), and when the rarefaction effect involved, it is then presented as a function of the Knudsen number (Kn). In this work, a new drag coefficient correlation for spherical particles is proposed based on direct numerical simulations, which well considers both the influences of finite Reynolds (0.1≤Re≤3.5) and Knudsen numbers (0.1≤Kn≤1). The simulations are performed using the lattice Boltzmann method coupled with an improved effective relaxation time model to account for the effect of finite Kn. The results show that the classical Cunningham-type correlation is not sufficient as Re>0.1, which can underestimate the drag coefficient with a maximum error about 27.1% at Kn=0.1 and 4.2% at Kn=1.0. Moreover, the drag coefficient expressions cannot be obtained by simply combining the formulas with pure slip and inertial effects considered separately, which usually overestimate the drag coefficient. [ABSTRACT FROM AUTHOR]

This paper investigates a formation control technique for low-Earth orbit satellites using moving masses. The moving mass control mechanism is conducted to reveal the controllability between the attitude and the offsets of moving masses, which shows that the moving masses only provide limited attitude control. Thus, the magnetic actuators are considered to offer an additional control degree of freedom. Then, to achieve the desired formation control, the aerodynamic force generated by changing attitudes is used orbital maneuvering. Considering the perturbations in the orbit dynamics at low-Earth orbit, a formation control law based on Nash game is developed against the disturbance described as a player. Furthermore, to deal with the offset saturation of moving masses, an adaptive controller is investigated. A simulation of two satellites formation is performed to validate the feasibility of the proposed formation control method. [ABSTRACT FROM AUTHOR]