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In this paper, the problem of finite-time state estimation for delayed periodic neural networks over multiple-packet transmission is addressed. The components of measurement output are separately transmitted by multiple-packet transmission, and the randomly occurring packet dropouts of different channels are described by mutually independent Bernoulli processes. In order to improve the robustness of the estimator, a non-fragile estimator is designed. In addition, some sufficient criteria are given to ensure that the estimation error system is stochastically finite-time stable and stochastically finite-time bounded, and the gains of non-fragile estimator are then derived based on these results. Finally, simulation results are provided to illustrate the effectiveness of the proposed estimator design approach.

In this issue of Cell Chemical Biology, new methods are reported to interrogate histone interactions and modifications. Kleiner et al. (2018) develop a chemical proteomics platform for profiling of direct, context-dependent histone-protein interactions in living cells, and Delachat et al. (2018) engineer fluorescent sensors for coexisting histone modifications in live stem cells.

This paper presents an analysis of the pull-in instability and vibrational behaviors for a multi-layer microbeam actuated electrostatically. Based on the accurate geometrically nonlinear theory of Euler–Bernoulli beams, a distributed electromechanical model that accounts for finite deformation and residual stress is proposed. The governing differential equations are established in the form similar to those of the single-layer beam theory by re-determination of the neutral axis. These equations, in conjunction with corresponding boundary conditions, are transformed into two two-point boundary value problems. The geometrical nonlinearity is taken into account in static deformation research. The pull-in parameters are obtained using the shooting method through taking the applied voltage as an unknown and the central deflection as a control parameter. The same algorithm is applied to the small-amplitude free vibration around the predeformed bending configuration following an assumed harmonic time mode. The corresponding fundamental natural frequency is presented. The proposed method is validated by comparing several case studies with available published simulations. The influences of pivotal parameters on the pull-in instability behavior and natural frequency are examined, including the length, thickness and residual stress of the microbeam.

The pull-in instability and the vibration for a prestressed circular electrostatically actuated microplate are investigated in consideration of the Casimir force. Based on von Karman’s nonlinear bending theory of thin plates, the governing equations for the whole analysis are decomposed into two two-point boundary value problems. For static deformation of the plate, the geometric nonlinearity is involved and the pull-in parameters are obtained by using the shooting method through taking the applied voltage or Casimir parameter as an unknown. This algorithm is also used to study the small amplitude free vibration about the predeformed bending configuration following an assumed harmonic time mode, and the variation of the prestress and Casimir parameters dependent fundamental natural frequency with the applied voltage is presented. Several case studies are compared with available published simulations to confirm the proposed method. The influences of various parameters, such as the initial gap-thickness ratio, Casimir effect, prestress on the pull-in instability behavior and the natural frequency are examined.