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Glycolysis is vital for the excessive proliferation of keratinocytes in psoriasis, and uridine phosphorylase‐1 (UPP1) functions as an enhancer of cancer cell proliferation. However, little is known about whether UPP1 promotes keratinocyte proliferation and accelerates psoriasis development. This study revealed that UPP1 facilitates cell viability and cell‐cycle progression in human epidermal keratinocytes (HEKs) by modulating the glycolytic pathway. Bioinformatics analysis of UPP1 gene expression and its correlation with the Reactome revealed that UPP1 mRNA expression, cell‐cycle progression, the interleukin‐6 (IL‐6)/Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathway and glycolysis were positively associated with psoriasis. Cell proliferation, the cell cycle and glycolysis were evaluated after UPP1 was silenced or overexpressed. The results showed that UPP1 overexpression increased cell proliferation, cell‐cycle progression and glycolysis, which was contrary to the effects of UPP1 silencing. However, the STAT3 inhibitor diminished UPP1 expression because STAT3 can bind to the UPP1 promoter. In conclusion, UPP1 was significantly activated by the IL‐6/STAT3 pathway and could modulate glycolysis to regulate cell proliferation and cell‐cycle progression in keratinocytes during the development of psoriasis. [ABSTRACT FROM AUTHOR]

With the participation in automatic generation control (AGC), a large-scale wind farm should distribute the real-time AGC signal to numerous wind turbines (WTs). This easily leads to an expensive computation for a high-quality dispatch scheme, especially considering the wake effect among WTs. To address this problem, a hierarchical power control (HPC) is constructed based on the geographical layout and electrical connection of all the WTs. Firstly, the real-time AGC signal of the whole wind farm is distributed to multiple decoupled groups in proportion of their regulation capacities. Secondly, the AGC signal of each group is distributed to multiple WTs via the data-driven surrogate-assisted optimization, which can dramatically reduce the computation time with a small number of time-consuming objective evaluations. Besides, a high-quality dispatch scheme can be acquired by the efficient local search based on the dynamic surrogate. The effectiveness of the proposed technique is thoroughly verified with different AGC signals under different wind speeds and directions. [ABSTRACT FROM AUTHOR]

The state-norm estimation problem for the switched nonlinear system under a more generalized type of switching signals is investigated in this paper. The component subsystems consist of input/output-to-state stability (IOSS) and non-IOSS continuous systems simultaneously, whose activation time is lower and upper bounded by mode-dependent time-varying functions, respectively. The considered switching signals satisfy mode-dependent time-varying constraints, whose switching number can grow faster than those with constant average dwell time condition. Then based on multiple IOSS Lyapunov functions method, the existence condition and design method for the switched state-norm estimator are proposed. The obtained results present extensions compared with the existing results, which are applicable for the more general situations. Finally, the effectiveness and improvement of the proposed approach are illustrated by a numerical example. [ABSTRACT FROM AUTHOR]

This paper investigates the input-to-state stability (ISS) for the switched nonlinear system (SNS) under edge-dependent switching signals, which consists of both ISS and non-ISS subsystems. Sufficient conditions ensuring the ISS properties of the SNS are proposed, which indicate that the switched system is ISS if the edge-dependent average dwell time is large enough and the activation time of non-ISS subsystems is comparatively small. The established criterion is quite general and makes an improvement compared with the existing related results. A numerical example and a chemical process are provided to illustrate the advantage and effectiveness of the theoretical result. [ABSTRACT FROM AUTHOR]

The event-triggered control problem for discrete-time switched linear systems with packet losses is addressed in this paper. It is assumed that, at each event-triggered instant transmitted successfully, the controller can only access the transmitted information of system state and mode. In both cases of packet losses and no packet losses, mode dependent event-triggered transmission schemes are proposed. And the closed-loop system is modeled as a switched system with augmented switching signal. Then, based on the multiple Lyapunov function method, in the case of packet losses, exponential stability conditions are given with constraint of the maximum allowable number of successive packet losses, and design methods for state feedback controller gains and mode dependent event-triggered parameters are obtained. Finally, the effectiveness and improvement of the proposed approach are illustrated by a numerical example. [ABSTRACT FROM AUTHOR]

In this work, single Au nanowire electrodes (AuNWEs) were fabricated by laser-assisted pulling/hydrofluoric acid (HF) etching process, which then were characterized by transmission electron microscopy (TEM), electrochemical method and finite-element simulation. The as-prepared single AuNWEs were used to construct electrochemical aptamer-based nanosensors (E-AB nanosensors) based on the formation of Au-S bond that duplex DNA tagged with methylene blue (MB) was modified on the surface of electrode. In the presence of adenosine triphosphate (ATP), the MB-labeled aptamer dissociated from the duplex DNA due to the strong specific affinity between aptamer and target, which lead to the reduction of MB electrochemical signals. Moreover, BSA was employed to further passivate electrode surface bonding sites for the stable of the sensor. The as-prepared E-AB nanosensor has been used for ATP assay with excellent sensitivity and selectivity, even in a complex system like cerebrospinal fluid of rat brain. Considering the unique properties of good stability, larger surface area and smaller overall dimensions, this E-AB nanosensor should be an ideal platform for widely sensing applications in living bio-system. [ABSTRACT FROM AUTHOR]

This paper considers the event-triggered H ∞ filtering problem for continuous-time switched linear systems. It is assumed that only the information of system output and switching signal is available to the filter at each event-triggered sampling instant. Based on a mode dependent event-triggered sampling scheme, the filtering error system is modeled as a switched system with augmented switching signal. Then, by the average dwell time technique and multiple Lyapunov function method, a new sufficient condition is obtained such that the filtering error system is exponentially asymptotically stable and satisfies the weighted H ∞ performance. The design method for the filter and event-triggered parameters is formulated by solving a set of linear matrix inequalities. Finally, the effectiveness of the proposed approach is illustrated by two numerical examples. [ABSTRACT FROM AUTHOR]

This paper addresses networked control problem for discrete-time linear singular systems over unreliable channel. It is assumed that the controller can only receive the transmitted sequence of finite coded signals via unreliable channels, which may be lost due to the limited communication capacity and transmission errors. By introducing compensation terms at every update instant and auxiliary systems in each sampling interval, both state- and output-based coder-decoder-controller procedures are proposed. Then, a uniform sufficient feedback stabilization condition involving the size of coding alphabet, the sampling period and data packet dropout rate is obtained. Finally, an example is given to illustrate the design procedures and effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

This study addresses the stability problem for linear continuous‐time Markovian switching singular systems. Based on a refined description for jumps of the system states at the switching instants, sufficient conditions for exponential stability in the mean‐square sense of the Markovian switching singular system are obtained by means of multiple Lyapunov function method. The obtained results present a new analysis of the impact for switching law‐induced state jump on the stability property of the considered system. Numerical examples are presented to illustrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Abstract: The simultaneous semi-global -stabilization and asymptotic stabilization in both semi-global and global cases are considered for continuous-time linear singular systems subject to input saturation. Based on the asymptotical property of the parametric generalized algebraic Riccati equations, a low-and-high gain state feedback control law and a scheduling technique are proposed. When applied to the singular system subject to input saturation and external disturbance, the semi-global finite-gain -stabilization and semi-global/global asymptotic stabilization are obtained simultaneously. The obtained results reduce to the existing ones for non-singular linear systems when the linear singular system reduces to a non-singular system. Furthermore, our results also improve the semi-global stabilization results for singular systems with saturation in the absence of the external disturbance. [Copyright &y& Elsevier]

This paper addresses the network-based control problem for a class of descriptor systems in the discrete-time domain with random delays. By modeling the sensor-to-controller and controller-to-actuator delays as Markovian chains, the closed-loop system can be expressed as a jump linear descriptor system with two modes. The stochastically admissible necessary and sufficient condition for the closed-loop system is constructed. An explicit expression for the desired controller is given without any system decomposition. The obtained results are formulated in terms of strict linear matrix inequalities (LMIs). In addition, an example is given to illustrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

The H∞ filtering problem for continuous-time linear systems is considered in which the amplitude saturation of the measurements of the system and the input of the filter are taken into account. An linear matrix inequality-based design approach is presented for the desired filter such that the resulting error system is local exponential asymptotical stable while regional L2 gain satisfies a prescribed H∞-norm bound constraint. Both the filter design with the minimum attenuation level bound and the estimation of the largest domain of attraction are formulated into convex optimization problems. [ABSTRACT FROM PUBLISHER]

The event-triggered control problem for discrete-time switched linear systems with network transmission delays is investigated in this paper. It is assumed that the controller can only access the transmitted information of system state and mode at each event-triggered instant. A mode dependent event-triggered transmission scheme is proposed and the closed-loop system is modeled as a switched system with delayed state and augmented switching signal. Then based on the multiple Lyapunov functional method, an exponential stability condition and design method for state feedback controller gains are obtained. The proposed approach leads an important step to study the event-triggered control for discrete-time switched systems. Finally, the effectiveness and improvement of the proposed approach are illustrated by a numerical example. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Single Hg nanoelectrodes were fabricated by single nucleation/growth of mercury on single gold nanodisk electrodes. • Pb2+ and Cu2+ could be accumulated and melted with single Hg nanoelectrodes (amalgam formed) through preconcentration step. • A novel nanosensor was established for simultaneous detection of lead and copper with high sensitivity and selectivity. Abstract In this paper, single Hg nanoelectrodes were prepared by single nucleation/growth of mercury on the surface of single gold nanodisk electrodes, which were fabricated by improved laser-assisted pulling method. The nucleation/growth process was characterized by scanning electron microscopy (SEM), transition electron microscopy (TEM) and electrochemical method. Pb2+ and Cu2+ could be accumulated and melted with single Hg nanoelectrodes (amalgam formed) through preconcentration step, and then two typical anodic waves would be obtained through square-wave anodic stripping voltammetry (SWASV) method. The peak currents were corresponded to the concentration of Pb2+ and Cu2+, and thus the single Hg nanoelectrodes could be used as a kind of novel nanosensor for simultaneous detection of lead and copper with high sensitivity and selectivity. [ABSTRACT FROM AUTHOR]

Single Au nanowire electrodes and single Pt@Au nanowire electrodes showed steady-state voltammetric responses and a fast electron-transfer rate, which have been used to fabricate an E-DNA sensor and investigate the oxygen reduction reaction at the single nanowire level. [ABSTRACT FROM AUTHOR]

This paper considers the event-triggered H ∞ filtering problem for discrete-time linear systems subject to package dropouts. The system measurement output is quantized before transmitted through the communication network with limited capacity. The event-triggered transmission mechanism is proposed and Bernoulli process is utilized to describe the package dropouts. A new sufficient condition is obtained such that the resulted error system is mean square exponentially stable and the filtering error satisfies the prescribed H ∞ performance. Then, co-design algorithm for the parameters of filter and event-triggered condition is presented by means of linear matrix inequality approach. Moreover, the minimum attenuation level bound can be obtained by solving a convex optimization problem. Numerical simulations show the effectiveness and less conservativeness of the proposed approach. [ABSTRACT FROM AUTHOR]

• The input-to-state stability (ISS) for discrete-time switched nonlinear system (DTSNS) containing non-ISS subsystems is investigated. • The switching signal is characterized by the edge-dependent average dwell time (EDADT), which presents a generalization of mode-dependent average dwell time (MDADT) and can further relax the constraints on switching signals. • Sufficient conditions are proposed to guarantee the ISS of the considered DTSNS, provided that the switching is not too fast and the activation time of non-ISS subsystems is comparatively short. • The obtained result includes a new less restrictively asymptotical stability condition as a special case for DTSNS with both stable and unstable subsystems when inputs are not considered. This paper investigates the input-to-state stability (ISS) for discrete-time switched nonlinear system (DTSNS) with generalized switching signals, which contains some subsystems that are not input-to-state stable (non-ISS). Sufficient conditions are proposed to guarantee the ISS of the considered DTSNS, provided that the switching is not too fast and the activation time of non-ISS subsystems is comparatively short. Some improvements are made when comparing with the existing related results, which is illustrated by a numerical example. [ABSTRACT FROM AUTHOR]

SUMMARY This paper discusses the exponential stability and stabilization for nonlinear descriptor systems with discrete and distributed delays. In terms of the Lyapunov method, the exponential stability of the slow subsystem is firstly obtained. Then, a new homotopy-based approach is proposed to investigate the exponential stability of the fast subsystem. By an estimate of the weighted matrix norm for a nonlinear mapping, the exponential stability of the fast subsystem and thus delay-dependent sufficient conditions for the exponential stability of the systems are obtained. In addition, a state feedback controller is designed for the stabilization of the nonlinear descriptor systems. Finally, the effectiveness of the proposed approach is illustrated by numerical examples. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]