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This paper investigates the issue of finite-time tracking control for flexible-joint robots. In the design scheme, the unknown continuous function is identified by a fuzzy system. By introducing the command filter technique, “explosion of complexity” problem which arises from repeated differentiation of virtual controllers is avoided. Meanwhile, errors resulting from the first-order filters can be reduced with the introduced compensation signal. Besides, the proposed method ensures that the tracking performance could be achieved within a limited time. Eventually, the simulation is given to demonstrate the effectiveness of the proposed scheme.

Distant metastasis is the major cause of colon cancer (CC) treatment failure. SAD1/UNC84 domain protein-2 (SUN2) is a key component of linker of the nucleoskeleton and cytoskeleton (LINC) complexes that may be relevant for metastasis in several cancers. Here, we first confirmed that SUN2 levels were significantly lower in primary CC tissues and distant metastasis than in normal colon tissues, and high SUN2 expression predicted good overall survival. Overexpression of SUN2 or knockdown of SUN2 inhibited or promoted cell migration and invasion in vitro, respectively. Moreover, silencing of SUN2 promoted metastasis in vivo. Mechanistically, we showed that SUN2 exerts its tumour suppressor functions by decreasing the expression of brain derived neurotrophic factor (BDNF) to inhibit BDNF/ tropomyosin-related kinase B (TrkB) signalling. Additionally, SUN2 associated with SIRT1 and increased the acetylation of methyl-CpG binding protein 2 (MeCP2) to increase its occupancy at the BDNF promoter. Taken together, our findings indicate that SUN2 is a key component in CC progression that acts by inhibiting metastasis and that novel SUN2-SIRT1-MeCP2-BDNF signalling may prove to be useful for the development of new strategies for treating patients with CC.

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An adaptive controller is constructed for a class of stochastic manipulator nonlinear systems in this paper. The states are constrained in the compact set. A tan-type Barrier Lyapunov Function (BLF) is employed to deal with state constraints. The proposed control scheme guarantees the output error convergence to a small neighbourhood of zero. All the signals in the closed-loop system are bounded. The simulation results illustrate the validity of the proposed method.