Stabilization and Controller Design of 2D Discrete Switched Systems with State Delays under Asynchronous Switching

This paper is concerned with the problem of robust stabilization for a class of uncertain two-dimensional (2D) discrete switched systems with state delays under asynchronous switching. The asynchronous switching here means that the switching instants of the controller experience delays with respect to those of the system. The parameter uncertainties are assumed to be norm-bounded. A state feedback controller is proposed to guarantee the exponential stability. The dwell time approach is utilized for the stability analysis and controller design. A numerical example is given to illustrate the effectiveness of the proposed method

Mixed L-/L1 fault detection filter design for fuzzy positive linear systems with time-varying delays

This study investigates the problem of fault detection for a class of fuzzy positive systems with time-varying delays. A new fault sensitivity measure, called L- index, is proposed. The L- fault detection filter design and multiobjective L-/L1 fault detection filter design problems are addressed. A co-positive type Lyapunov-Krasovskii functional is constructed for the performance analysis and fault detection filter design. Sufficient conditions for the existence of such two filers are firstly given, and then the design methods are presented. Finally, two examples are provided to show the effectiveness and applicability of the proposed method. © The Institution of Engineering and Technology 2014

Input-output finite-time stability of discrete-time impulsive switched linear systems with state delays

This paper is concerned with the problem of input-output finite-time stability (IO-FTS) for discrete impulsive switched systems with state delays. Sufficient conditions are presented for the existence of IO-FTS for such systems under the cases of certain switching, arbitrary switching, and uncertain switching. All the obtained results are formulated in a set of linear matrix inequalities (LMIs). Two numerical examples are given to illustrate the effectiveness of the proposed results

Correlation of serum amyloid A levels, clinical manifestations, treatment, and disease activity in patients with acute anterior uveitis

Purpose: To investigate the association between serum amyloid A (SAA) protein and the clinical features of acute anterior uveitis (AAU), and to evaluate the disease activity and treatment effect in relation to SAA levels. Methods: AAU patients and healthy individuals were recruited from October 2016 to August 2017 at the Department of Uveitis, in the Eye Hospital of Wenzhou Medical University. Related demographic, clinical characteristics, and therapeutic data were analyzed. Results: One hundred and eight AAU patients and 18 healthy controls were included in this study. Serum SAA levels in AAU patients were significantly higher than those of healthy controls (p all +AAU patients than those in AS−AAU patients (p +AAU compared with those with HLA-B27−AAU (p < 0.05). Furthermore, in each of the AAU subgroups, higher SAA levels were observed in the active state than those in the inactive state (p all < 0.05). In addition, SAA levels were positively correlated to anterior chamber cell counts (r = 0.492, p < 0.0001). ROC curve analysis revealed that SAA had an AUC value of 0.727 for detecting active inflammation (Youden’s index = 0.38). SAA decreased with effective treatments (p = 0.0002). Conclusion: Serum levels of SAA were elevated in AAU patients. The increased levels of SAA were correlated with AS and HLA-B27 status. SAA levels were also positively correlated to disease activity and decreased with effective treatments. These findings suggest that SAA is associated with AAU, with a potential role in monitoring inflammatory processes and assessing the efficacy of therapy.</p

The Bi-Functional Paxilline Enriched in Skin Secretion of Tree Frogs (<i>Hyla japonica</i>) Targets the KCNK18 and BK_Ca Channels

The skin secretion of tree frogs contains a vast array of bioactive chemicals for repelling predators, but their structural and functional diversity is not fully understood. Paxilline (PAX), a compound synthesized by Penicillium paxilli, has been known as a specific antagonist of large conductance Ca2+-activated K+ Channels (BKCa). Here, we report the presence of PAX in the secretions of tree frogs (Hyla japonica) and that this compound has a novel function of inhibiting the potassium channel subfamily K member 18 (KCNK18) channels of their predators. The PAX-induced KCNK18 inhibition is sufficient to evoke Ca2+ influx in charybdotoxin-insensitive DRG neurons of rats. By forming π-π stacking interactions, four phenylalanines located in the central pore of KCNK18 stabilize PAX to block the ion permeation. For PAX-mediated toxicity, our results from animal assays suggest that the inhibition of KCNK18 likely acts synergistically with that of BKCa to elicit tingling and buzzing sensations in predators or competitors. These results not only show the molecular mechanism of PAX-KCNK18 interaction, but also provide insights into the defensive effects of the enriched PAX