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This paper focuses on speed tracking control of the maglev train operation system. Given the complexity and instability of the maglev train operation system, traditional speed-tracking control algorithms demonstrate poor tracking accuracy and large tracking errors. The maglev train is easily affected by external interference, increasing train energy consumption and reducing passengers’ riding comfort. This study proposes a control algorithm called APSO-NLADRC to address the deficiencies of the automatic train operation control algorithms. The APSO-NLADRC is based on adaptive particle swarm optimization (APSO) algorithm parameter optimization nonlinear active disturbance rejection controller (NLADRC). The method of population comparison, linear update of learning factors, and adaptive updating of inertia weight values addresses the premature convergence phenomenon that occurs during the parameter optimization of the traditional particle swarm algorithm. The APSO algorithm solves the problem that the parameters of the NLADRC are difficult to adjust. Compared with PID, NLADRC, and NLADRC based on traditional particle swarm optimization algorithms, the proposed control algorithm has higher tracking accuracy and more robust anti-interference capability and provides better comfort.

Background The main cause of severe chronic venous insufficiency is deep venous incompetence. Deep venous reconstructive surgeries are reserved for cases that do not show a good response to conservative therapies. Method We present the case of a 68-year-old man presenting with swelling, pain, and pigmentation in his left lower limb for 14 years and ulcers for 10 years. Descending venography identified a Kistner’s grade IV reflux in the deep vein of the left lower limb. Internal valvuloplasty was performed following Kistner’s method. Meanwhile, external wrapping with a 1-cm-wide polyester-urethane vascular patch was performed to strengthen the vein wall in the venospasm condition. Results Symptoms were immediately relieved postoperatively. Refractory ulcers healed five months after the procedure. At the six-month follow-up, color duplex ultrasound of the deep vein of the left lower limb showed no reflux in the proximal segment of the femoral vein. Conclusion Internal valvuloplasty combined with sleeve wrapping is feasible in the treatment of severe deep venous incompetence with good short-term results.

Caged 4-oxa-tricyclo[4.3.1.03,7]dec-2-one structural motifs are found in Garcinia natural products that demonstrate anti-tumor activity. Gambogic acid (GA, 1), the most abundant caged Garcinia xanthones, has been reported to be a promising anti-cancer agent. To identify the essential pharmacophore for its anti-tumor activity, a series of GA analogues that address potential key structural features for biological activity were synthesized, among which compound 11a displayed comparable in vitro anti-tumor activity as GA. Mechanistic studies on 11a determined that the compound induces apoptosis as well as arrests the G2/M phase of the cell cycle in HepG2 cells. The determination of the essential part of the scaffold found in GA to maintain anti-tumor effects, and the SAR based on the caged pharmacophore are reported and will provide key information for future anti-cancer drug development studies.