Piwi-interacting RNAs (piRNAs) silence transposons to safeguard genome integrity in animals. However, the functions of the many piRNAs that do not map to transposons remain unknown. Here, we show ...that piRNA targeting in
can tolerate a few mismatches but prefer perfect pairing at the seed region. The broad targeting capacity of piRNAs underlies the germline silencing of transgenes in
Transgenes engineered to avoid piRNA recognition are stably expressed. Many endogenous germline-expressed genes also contain predicted piRNA targeting sites, and periodic An/Tn clusters (PATCs) are an intrinsic signal that provides resistance to piRNA silencing. Together, our study revealed the piRNA targeting rules and highlights a distinct strategy that
uses to distinguish endogenous from foreign nucleic acids.
This article addresses the distributed model-free adaptive control (DMFAC) problem for learning nonlinear multiagent systems (MASs) subjected to denial-of-service (DoS) attacks. An improved dynamic ...linearization method is proposed to obtain an equivalent linear data model for learning systems. To alleviate the influence of DoS attacks, an attack compensation mechanism is developed. Based on the equivalent linear data model and the attack compensation mechanism, a novel learning-based DMFAC algorithm is developed to resist DoS attacks, which provides a unified framework to solve the leaderless consensus control, the leader-following consensus control, and the containment control problems. Finally, simulation examples are shown to illustrate the effectiveness of the developed DMFAC algorithm.
This article is concerned with the event-triggered output consensus problem for heterogeneous multiagent systems (MASs) with nonuniform communication delays. Unlike the existing event-triggered ...consensus results, more general heterogeneous linear MASs and nonuniform communication delays are considered. To reduce communication among subsystems, novel dynamic periodic event-triggered mechanisms are proposed. By using the event-triggered signals at the previous sampling instant, new distributed observers are designed to eliminate asynchronous behavior caused by nonuniform communication delays. Based on the developed observers, the observer error system is converted into a time-delay system with interval time-varying delays. Besides, a controller is designed by using the states of observers. It is shown that the consensus problem can be solved by the proposed method. Finally, an illustrative example is provided to verify the effectiveness of the developed method.
This article discusses the prescribed performance control problem for multiagent systems involving the state triggering and the controller output triggering simultaneously. To successfully apply the ...backstepping technique in the event-triggered control design, the virtual control signal is constructed by the original system state. Compared with the existing results on the prescribed performance, a new barrier Lyapunov function is developed with considering the characteristics of multiagent systems, and a fuzzy adaptive event-triggered control protocol is proposed by the backstepping procedure. It guarantees that the consensus tracking error converges to a predefined region of the origin in a preset finite time. At the same time, all other closed-loop signals remain bounded without the Zeno behavior. Finally, a simulation example confirms the availability of the developed control scheme with a comparison.
In this paper, the H∞$$ {H}_{\infty } $$ optimal output tracking control problem for Markov jump systems is investigated, where the two cases with known or completely unknown transition probabilities ...are both considered. Based on game theory and H∞$$ {H}_{\infty } $$ performance, quadratic cost is considered, where a discount parameter is introduced into the quadratic cost in order to track unstable systems and eliminate the assumption that the noise energy is bounded. The game coupled algebraic Riccati equation and the corresponding controller are presented by dynamic programming. The stochastic stability of the tracking error system is further investigated. Moreover, iterative and reinforcement learning‐based algorithms are proposed for solving the H∞$$ {H}_{\infty } $$ optimal tracking controller with known or completely unknown transition probabilities, respectively. Finally, some numerical simulations on a DC motor are performed to validate the effectiveness of the proposed results.
This article studies the observer-based event-triggered containment control problem for linear multiagent systems (MASs) under denial-of-service (DoS) attacks. In order to deal with situations where ...MASs states are unmeasurable, an improved separation method-based observer design method with less conservativeness is proposed to estimate MASs states. To save communication resources and achieve the containment control objective, a novel observer-based event-triggered containment controller design method based on observer states is proposed for MASs under the influence of DoS attacks, which can make the MASs resilient to DoS attacks. In addition, the Zeno behavior can be eliminated effectively by introducing a positive constant into the designed event-triggered mechanism. Finally, a practical example is presented to illustrate the effectiveness of the designed observer and the event-triggered containment controller.
This publication offers modern, state‐of‐the‐art International Neural Monitoring Study Group (INMSG) guidelines based on a detailed review of the recent monitoring literature. The guidelines outline ...evidence‐based definitions of adverse electrophysiologic events, especially loss of signal, and their incorporation in surgical strategy. These recommendations are designed to reduce technique variations, enhance the quality of neural monitoring, and assist surgeons in the clinical decision‐making process involved in surgical management of recurrent laryngeal nerve. The guidelines are published in conjunction with the INMSG Guidelines Part II, Optimal Recurrent Laryngeal Nerve Management for Invasive Thyroid Cancer–Incorporation of Surgical, Laryngeal, and Neural Electrophysiologic Data.
Laryngoscope, 128:S1–S17, 2018
The problem of finite-time adaptive tracking control against event-trigger error is investigated in this article for a type of uncertain nonlinear systems. By fusing the techniques of command filter ...backstepping technical and event-triggered control (ETC), an adaptive event-triggered design method is proposed to construct the controller, under which the effect of event-triggered error can be compensated completely. Moreover, the proposed controller can increase robustness against uncertainties and event error in the backstepping design framework. In particular, we establish the finite-time convergence condition under which the tracking error asymptotically converges to zero in finite time with the aid of a scaling function. Detailed and rigorous stability proofs are given by making use of the improved finite time stability criterion. Two simulation examples are provided to exhibit the validity of the designed adaptive ETC approach.
Background
Few studies in the literature have reported recovery data for different types of recurrent laryngeal nerve injuries (RLNIs). This study is the first attempt to classify RLNIs and rank them ...by severity.
Methods
This prospective clinical study analyzed 281 RLNIs in which a true loss of signal was identified by intraoperative neuromonitoring (IONM), and vocal cord palsy (VCP) was confirmed by a postoperative laryngoscope. For each injury type, the prevalence of VCP, the time of VCP recovery, and physical changes on nerves were analyzed. Additionally, different RLNI types were experimentally induced in a porcine model to compare morphological change.
Results
The overall VCP rate in at-risk patients/nerves was 8.9/4.6 %, respectively. The distribution of RLNI types, in order of frequency, was traction (71 %), thermal (17 %), compression (4.2 %), clamping (3.4 %), ligature entrapment (1.6 %), suction (1.4 %), and nerve transection (1.4 %). Complete recovery from VCP was documented in 91 % of RLNIs. Recovery time was significantly faster in the traction group compared to the other groups (
p
< 0.001). The rates of temporary and permanent VCP were 98.6 and 1.4 % for traction lesion, 72 and 28 % for thermal injury, 100 and 0 % for compression injury, 50 and 50 % for clamping injury, 100 and 0 % for ligature entrapment, 100 and 0 % for suction injury, and 0 and 100 % for nerve transection, respectively. Physical changes were noted in 14 % of RLNIs in which 56 % of VCP was permanent. However, among the remaining 86 % IONM-detectable RLNIs without physical changes, only 1.2 % of VCP was permanent. A porcine model of traction lesion showed only distorted outer nerve structure, whereas the thermal lesion showed severe damage in the inner endoneurium.
Conclusions
Different RNLIs induce different morphological alterations and have different recovery outcomes. Permanent VCP is rare in lesions that are visually undetectable but detectable by IONM. By enabling early detection of RLNI and prediction of outcome, IONM can help clinicians plan intra- and postoperative treatment.
In this article, we consider the cooperative tracking problem for a class of nonlinear multiagent systems (MASs) with unknown dynamics under denial-of-service (DoS) attacks. To solve such a problem, ...a hierarchical cooperative resilient learning method, which involves a distributed resilient observer and a decentralized learning controller, is introduced in this article. Due to the existence of communication layers in the hierarchical control architecture, it may lead to communication delays and DoS attacks. Motivated by this consideration, a resilient model-free adaptive control (MFAC) method is developed to withstand the influence of communication delays and DoS attacks. First, a virtual reference signal is designed for each agent to estimate the time-varying reference signal under DoS attacks. To facilitate the tracking of each agent, the virtual reference signal is discretized. Then, a decentralized MFAC algorithm is designed for each agent such that each agent can track the reference signal by only using the obtained local information. Finally, a simulation example is proposed to verify the effectiveness of the developed method.
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