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Spinal cord injury (SCI) causes immune activation of resident microglia. Activated microglia have two different phenotypes, the pro-inflammatory classically activated (M1) phenotype and the anti-inflammatory alternatively activated (M2) phenotype. M1 phenotype microglia are the key factor in inflammation. The treatment of SCI remains a huge challenge due to the nontargeting and inefficiency of anti-inflammatory drugs through the blood-brain barrier (BBB). The purpose of this experiment was to design M2-type primary peritoneal macrophages exosomes (Exos) as a drug carrier for berberine (Ber), which can be efficiently targeted to deliver drugs to the injured spinal cord due to the natural advantage of Exos across the BBB. The Exos were loaded with Ber by an ultrasonic method. In vitro and in vivo experiments confirmed that the loaded sample (Exos-Ber) could decrease the M1 protein marker iNOS, elevate the M2 protein marker CD206 and reduce inflammatory and apoptotic cytokines (TNF-α, IL-1β, IL-6, Caspase 9, Caspase 8), which showed that Exos-Ber had a good anti-inflammatory and anti-apoptotic effect by inducing microglia from the M1 phenotype to M2 phenotype polarization. Moreover, the motor function of SCI mice was significantly improved after Exos-Ber treatment, indicating that Exos-Ber is a potential agent for SCI therapy.

The SVPWM technique plays an important role in the DC-AC transform. The modeling and simulation for SVPWM were proposed in this paper. The sector calculating model and basic vector working time model were set up. The effective vector function of time was set up. The triangle wave symmetry modulation was established too. The simulation results show that the model proposed in this paper is effective and has application value.

Airfield lighting circuit is an important part of airfield lighting system, and the insulation resistance value of this circuit is affected by humidity, temperature, the quality and the number of the Isolation Transformers and many other factors, so it is difficult to accurately predict the resistance size by using traditional methods. In the light of insulation resistance values of airfield lighting circuit, this paper put forward adopting Gray System Theory to make the prediction, and then build GM(2,1) model to analyze and forecast the resistance values according to the actually measured values of the insulation resistance at Shanghai Pudong International Airport. Finally, the research shows that there is only a little difference between predicted values and the actually measured values. In other words, the prediction of insulation resistance based on Gray System Theory is viable.

Navigation light monitoring system is designed to detect the working condition of each light with circuit cable carrier. However, the real-time detecting information could be inaccurate as a result of the existence of disturbances such as noise, multi-path effect and channel decline, when the data transmission happens in light cable as the channel. In this paper, OFDM (Orthogonal Frequency Division Multiplexing) is presented to be used in circuit cable communication. And the reason and capability of the resistance to these disturbances in OFDM are analyzed. Finally, the result is concluded that OFDM used in navigation light cable channel is feasible.