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In this paper, a feedback control law based on two time‐scale assignment and state extension is implemented for the nonlinear non‐minimum phase dynamics of three degree‐of‐freedom autonomo...

Aim Autophagy is a self-protective process, and it confers cancer cells resistance against radio-chemotherapeutics. To induce cancer cell death, a series of compounds of 3-((4-((7-chloroquinolin-4-yl)amino)butyl)amino)-7-substituted benzo[e][1,2,4]triazine 1-oxide or CQBTO containing two critical chemical groups were designed and synthesized. One compound, benzo[e][1,2,4]triazine 1-oxide, yielded free radicals to trigger autophagy, and the other one, chloroquine (CQ), was an inhibitor of autophagy. We hypothesized that the compounds could kill cancer cells effectively by inducing incomplete autophagy. Methods In vitro cultured non-small cell lung carcinoma cells and primary lung tumors in mice in vivo were used to test the lethal effects of CQBTO on cancer cells and toxicity to normal tissues. Cell viability was examined using the CCK8 assay. Genomic instability was determined with the cytochalasin B-blocked micronucleus assay. Cell cycle distribution was analyzed by propidium iodide staining and flow cytometry. Western blotting and immunofluorescence were used to detect the induction and localization of LC3, a biomarker for autophagy. Results Compared with CQ, three CQBTO compounds were lethal to lung cancer cells, and CQBTO-3 was the most effective. The LD50 for CQBTO-3 was 21 μΜ in A549 cells and 21.5 μΜ in Calu-1 cells, which was lower than that of CQBTO-2 or CQBTO-1. Induction of LC3 foci and an increase in the LC3II/LC3I ratio demonstrated the induction of autophagy by CQBTO-3 in A549 cells, whereas no obvious micronuclei or cell cycle arrest was observed. No detectable toxicity to normal mice was observed. CQBTO-3 improved the quality of mouse life, reduced the number and size of existing tumors, and suppressed tumor formation. Conclusion CQBTO-3 is a potential chemical compound for lung cancer treatment.

Summary This paper proposes modified static anti-windup techniques for saturated systems with sector-bounded and slope-restricted nonlinearities by augmenting the pre-designed controller with the so-called differential compensator to process the slope restriction. By using a purely quadratic Lyapunov function and with a modified sector condition dealing with actuator saturation, LMI-based synthesis conditions are presented to address the problems of the estimates of the region of attraction and performance analysis of the closed-loop system. Numerical examples illustrate the effectiveness of the proposed approaches. Copyright © 2016 John Wiley & Sons, Ltd.

This paper addresses the robust and accurate trajectory tracking problem for unmanned helicopters in the presence of model uncertainties and external disturbances. First, the helicopter's model is simplified to a six-degrees-of-freedom rigid body augmented with a simplified rotor dynamic model, with the model uncertainties and the external disturbances being treated as lumped unknown disturbances. Second, a nonlinear disturbance observer is designed to estimate this lumped disturbance. Then, a backstepping controller with disturbance compensation is designed to ensure robust and highly trajectory tracking. After that, the theoretical analysis of the efficiency of the designed disturbance observer-based backstepping controller (Backstepping+DO) is shown by the Lyapunov theory. Finally, simulation results and conclusions are presented and discussed.