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Cytokines such as IL-6, TNF-α and IL-1β trigger inflammatory cascades which may play a role in the pathogenesis of chronic kidney disease (CKD)-associated cachexia. CKD was induced by 5/6 nephrectomy in mice. We studied energy homeostasis in Il1β−/−/CKD, Il6−/−/CKD and Tnfα−/−/CKD mice and compared with wild type (WT)/CKD controls. Parameters of cachexia phenotype were completely normalized in Il1β−/−/CKD mice but were only partially rescued in Il6−/−/CKD and Tnfα−/−/CKD mice. We tested the effects of anakinra, an IL-1 receptor antagonist, on CKD-associated cachexia. WT/CKD mice were treated with anakinra (2.5 mg/kg/day, IP) or saline for 6 weeks and compared with WT/Sham controls. Anakinra normalized food intake and weight gain, fat and lean mass content, metabolic rate and muscle function, and also attenuated molecular perturbations of energy homeostasis in adipose tissue and muscle in WT/CKD mice. Anakinra decreased serum and muscle expression of IL-6, TNF-α and IL-1β in WT/CKD mice. Anakinra attenuated browning of white adipose tissue in WT/CKD mice. Moreover, anakinra normalized gastrocnemius weight and fiber size as well as attenuated muscle fat infiltration in WT/CKD mice. This was accompanied by correcting the increased muscle wasting signaling pathways while promoting the decreased myogenesis process in gastrocnemius of WT/CKD mice. We performed qPCR analysis for the top 20 differentially expressed muscle genes previously identified via RNAseq analysis in WT/CKD mice versus controls. Importantly, 17 differentially expressed muscle genes were attenuated in anakinra treated WT/CKD mice. In conclusion, IL-1 receptor antagonism may represent a novel targeted treatment for adipose tissue browning and muscle wasting in CKD.

Direction of arrival (DOA) estimation of underwater multipath signals has become an indispensable part of many military and civil applications in the oceanic field. However, DOAs of different paths of the multipath signals may be the same or too close to be separated in space, which brings a great challenge to the DOA estimation of multipath signals. Besides, the number of multipath is generally unknown and time-varying in passive scenarios which generally lead to an underdetermined case. Therefore, it is essential to study an efficient algorithm to realize the underdetermined DOA estimation of underwater multipath signals in passive scenarios. This paper proposes a passive DOA estimation algorithm of underwater multipath signals via spatial time-frequency distributions (STFDs). Firstly, we establish a multipath signals model and utilize the quadratic time-frequency (TF) analysis method to reduce cross-terms while keeping a good resolution. Then, we estimate the number of multipath and introduce a novel multi-ridge detection technique to extract the TF trajectories of multipath signals, which adopts the idea of smoothing forward and backward, and the edge TF point detection strategy. Lastly, we estimate the DOA of each path of the multipath signals separately and realize source association based on the clustering-based method. Simulation results and analysis demonstrate that this algorithm can effectively improve the estimation accuracy of instantaneous frequency (IF) and DOA estimation of underwater multipath signals in underdetermined cases and passive situations.

Wenting Gong,1,&ast; Wen Tang,2,&ast; Lan Luo,3 Furong Zhang,1 Chenyang Cai,1 Jiangyan Zhang,1 Xiaolin Wu,4 Jianping Shang,4 Xiaolan Shu,2 Ting Wang,5 Danna Tu,6 Zhengjiang Jin,7,&ast; Ronghao Zheng4,&ast; 1Department of pharmacy, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 2Department of Pediatric Intensive Care Unit, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 3Department of Child Health, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 4Department of Pediatric Nephrology, Rheumatology, and Immunology, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 5Department of Pediatric Neurology, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 6Department of Pediatric Cardiology, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 7Department of Clinical Laboratory, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Ronghao Zheng, Department of Pediatric Nephrology, Rheumatology, and Immunology, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, 745 Wu luo Road, Hongshan District, Wuhan, 430070, Hubei Province, People’s Republic of China, Tel +86 02787169267, Email hytwo2001@126.com Zhengjiang Jin, Department of Clinical Laboratory, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, 745 Wu luo Road, Hongshan District, Wuhan, 430070, Hubei Province, People’s Republic of China, Email king199735@126.comPurpose: To explore the trends and correlation between antibiotics consumption and antimicrobial resistance in children in a specialist hospital from 2016– 2021 in China.Patients and Methods: This retrospective study investigated data on the consumption of antibiotics and antimicrobial resistance in children. Antibiotics consumption was expressed as defined daily doses (DDDs)/1000 patient-days based on the Guidelines for Anatomical Therapeutic Chemical. The trends in antibiotics consumption and antimicrobial resistance rates were analyzed by linear regression, while Spearman correlation analysis was employed to evaluate their correlations.Results: An increasing trend in the annual consumption of carbapenems and monobactams was detected (all P< 0.05). A significant upward trend was detected in the annual resistance rates of Enterococcus faecium to ciprofloxacin, Streptococcus pneumonia to ceftriaxone, Acinetobacter baumannii to carbapenems, Enterobacter cloacae to carbapenems, Pseudomonas aeruginosa to ceftazidime, and Escherichia coli to cefepime, while the annual resistance rates of Escherichia coli to carbapenems had a significant downward trend (all P< 0.05). The consumption of cephalosporin/β-lactamase inhibitor (C/BLI) combinations and carbapenems had significant positive correlations with the resistance rates of Acinetobacter baumannii to carbapenems (r=0.763, P< 0.001; r=0.806, P< 0.001), Enterobacter cloacae to carbapenems (r=0.675, P< 0.001; r=0.417, P=0.043), and Pseudomonas aeruginosa to ceftazidime (r=0.625, P=0.001; r=0.753, P< 0.001), respectively. Also, increasing consumption of monobactams was related to the upward resistance rates of Acinetobacter baumannii to carbapenems (r=0.557, P=0.005) and Enterobacter cloacae to carbapenems (r=0.507, P= 0.011).Conclusion: This study demonstrated significant positive associations between antibiotics consumption and specific antimicrobial resistance rates. The current findings pointed out some directions to pursue in controlling the prevalence of certain resistant bacterial strains in children.Keywords: antibiotic consumption, antimicrobial resistance, correlation, children

The efficacy of vitamin D supplementation in patients with systemic lupus erythematosus (SLE) remains uncertain. This meta-analysis aimed to systematically evaluate the efficacy and safety of vitamin D supplementation in patients with SLE.Randomized controlled trials (RCTs) were searched in PubMed, Embase, Cochrane CENTRAL and Web of Science databases. The retrieved studies were subjected to meta-analysis using the fixed-effect or random-effect model.Five eligible RCTs enrolling 490 participants were included. Compared to the placebo treatment, vitamin D supplementation significantly increased the level of serum 25-hydroxyvitamin D (25(OH)D) (5 trials, 490 participants: standard mean difference (SMD) = 2.072, 95% CI: 1.078-3.066, P0.001). The pooled result from 2 RCTs showed that vitamin D supplementation decreased the fatigue severity scale scores in patients with SLE (2 trials, 79 participants: SMD = -1.179, 95% CI: -1.897 to -0.460, P = 0.001). The SLE disease activity index scores and positivity of anti-double-stranded DNA antibodies (anti-dsDNA) did not differ significantly (4 trials, 223 participants: SMD = -0.507, 95% CI: -1.055-0.041, P = 0.070; 3 trials, 361 participants: Risk ratio = 0.880, 95% CI: 0.734-1.054, P = 0.165) between the vitamin D supplementation group and the placebo treatment group. None of the included studies reported severe adverse events associated with vitamin D supplementation.This meta-analysis suggested that vitamin D supplementation is effective in increasing the serum 25(OH)D levels, may improve fatigue, and is well-tolerated in patients with SLE, however, it does not seem to have significant effects in decreasing the positivity of anti-dsDNA and disease activity.

This paper presents a hierarchical structure to solve the consensus problem of multiagent systems. The new scheme divides the agents into several groups, with each group containing a value concerning all of the intragroup agents’ states, which we call group information . For each single agent, it receives not only the agent information from its intragroup neighbors, but also the group information from its neighboring groups. It is then shown that global consensus can be achieved under the proposed scheme in both discrete time and continuous time. Moreover, a sufficient condition to achieve average consensus is provided. This hierarchical model can be well used in the PageRank algorithm to reduce the communication loads, and to reveal the attractors for Boolean networks by reducing the computational complexity.

This paper focuses on the economic power dispatch problem in a smart grid by using the distributed consensus with event‐triggered communication mechanism based on continuous‐time multi‐age...

This paper presents a hierarchical framework to solve the multi-robot temporal task planning problem. We assume that each robot has its individual task specification and the robots have to jointly satisfy a global collaborative task specification, both described in linear temporal logic. Specifically, a central server firstly extracts and decomposes a collaborative task sequence from the automaton corresponding to the collaborative task specification, and allocates the subtasks in the sequence to robots. The robots can then synthesize their initial execution strategies based on locally constructed product automatons, combining the assigned collaborative tasks and their individual task specifications. Furthermore, we propose a distributed execution strategy adjusting mechanism to iteratively improve the time efficiency, by reducing wait time in collaborations caused by potential synchronization constraints. We prove the completeness of the proposed framework under assumptions, and analyze its time complexity and optimality. Extensive simulation results verify the scalability and optimization efficiency of the proposed method., 14 pages, 6 figures. arXiv admin note: text overlap with arXiv:2108.11597

We study the distributed Kalman filtering problem in relative sensing networks with rigorous analysis. The relative sensing network is modeled by an undirected graph while nodes in this network are running homogeneous dynamical models. The sufficient and necessary condition for the observability of the whole system is given with detailed proof. By local information and measurement communication, we design a novel distributed suboptimal estimator based on the Kalman filtering technique for comparison with a centralized optimal estimator. We present sufficient conditions for its convergence with respect to the topology of the network and the numerical solutions of n linear matrix inequality (LMI) equations combining system parameters. Finally, we perform several numerical simulations to verify the effectiveness of the given algorithms.

This paper investigates the distributed localization problem of sensor networks with mixed measurements. Each node holds a local coordinate system without a common orientation and is capable of measuring only one type of information (either distance, bearing, or relative position) to near-by nodes. Thus, three types of measurements are mixed in the sensor networks. Moreover, the communication topologies in the sensor networks may be time-varying due to unreliable communications. This paper develops a fully distributed algorithm called BCDL (Barycentric Coordinate based Distributed Localization) where each node starts from a random initial guess about its true coordinate and converges to the true coordinate via only local node interactions. The key idea in BCDL is to establish a unified linear equation constraints for the sensor coordinates by using the barycentric coordinates of each node with respect to its neighbors though the sensor nodes may have different types of measurements. Then a distributed iterative algorithm is proposed to solve the linear equations under time-varying communication networks. A necessary and sufficient graphical condition is obtained to ensure global convergence of the distributed algorithm.

This paper investigates the aggregated control problem of a large number of residential responsive loads for various demand response applications. A unified hybrid system model is proposed, capturing the dynamics of both TCLs (Thermostatically Controlled Loads) such as HVACs (Heating, Ventilating and Air Conditioning) and water heaters, and deferrable loads such as washers, dryers, and PHEVs (Plug-in Hybrid Electric Vehicle). Based on the unified hybrid system model, we formulate the aggregated control problem as an optimal control problem, which seeks for an optimal energy usage plan for a population of heterogeneous loads. We then propose a game-theoretic approach to develop a decentralized aggregated control algorithm. Convergence of the proposed algorithm is shown by employing potential game theory. The hybrid system modeling framework and the proposed decentralized aggregated control algorithm are validated through several realistic demand response simulations using GridLAB-D. The simulation results demonstrate that the aggregated power response can accurately track a reference trajectory, effectively reduce the peak power consumption, and efficiently save electricity cost.

In this paper we explore the problem of scheduling parallel processes of Kalman filters to meet individual estimation error requirements. It is assumed that at each time-step measurements of only one process are received. We define real-time deadlines of transmissions and convert the problem into arranging sequence of tasks with corresponding deadlines. To reduce computations, cycles of transmissions are calculated and virtual processes are introduced into scheduling. A sliding window method is then designed to adjust the processes against real-time disturbances in applications. Compared with algorithms proposed in Lin and Wang (2013), the proposed algorithm is able to schedule a feasible sequence adaptively within a short scheduling window and requires little computation.

This article investigates the controllability problem of multi-agent systems. Each agent is assumed to be governed by a second-order consensus control law corresponding to a directed and weighted graph. Two types of topology are considered. The first is concerned with directed trees, which represent the class of topology with minimum information exchange among all controllable topologies. A very simple necessary and sufficient condition regarding the weighting scheme is obtained for the controllability of double integrator multi-agent systems in this scenario. The second is concerned with a more general graph that can be reduced to a directed tree by contracting a cluster of nodes to a component. A similar necessary and sufficient condition is derived. Finally, several illustrative examples are provided to demonstrate the theoretical analysis results.

The paper studies the general circumnavigation problem for a team of unicycle-type agents, with the goal of achieving specific circular formations and circling on different orbits centered at a target of interest. A novel distributed solution is proposed, in which the control laws are heterogeneous for the agents such that some agents are repellant from the target while attractive to its unique neighbor and some agents are attractive to the target while repellant from its neighbor. A systematic procedure is developed to design the control parameters according to the specific radii of the orbits and the formations that the agents are desired to converge to. Moreover, this control scheme uses a minimum number of information flow links between the agents and local measurements of relative position only. Based on the block diagonalization of circulant matrices by a Fourier transform, asymptotic convergence properties are analyzed rigorously. The validity of the proposed control algorithm is also demonstrated through numerical simulations.

This paper addresses the problem of steering a single or a group of autonomous nonholonomic mobile robots to enclose a target of interest. We develop control schemes which require only local bearing measurements, and deal with encirclement of two types of targets: point target and disk target. When a single robot is used, circumnavigation schemes are proposed to achieve effective encirclement of the target. It is shown that under the proposed control schemes, the robot can circle the target from a prescribed distance without distance measurement. When multiple robots are deployed, the control schemes developed for single robot are modified by introducing a coordination mechanism, which drives the robots to distribute evenly around the target. We further discuss a control scheme that moves the robots to form a static circular formation around the target based on feedback linearization. All the proposed control schemes are validated in experiments on a group of two-wheeled differential drive mobile robots.

We study the rendezvous problem of multiple nonholonomic unicycle-type robots. Simple decentralized control laws are proposed in which each agent makes a decision only based upon the bearing angles of the other robots in its reference frame. The convergence is first proved when the interaction topology between robots is connected; then for the complete interaction case, it is proved that under the proposed control law, the perimeter of the convex hull defined by the positions of robots decays all the time. Consequently, all the robots converge to a common point. It is also proved that the meeting point is located in a bounded region which is determined by the robots’ initial positions. Simulations illustrate the theoretical results and the performance with measurement errors.

The integration of modern computing and advanced communication with power grids has led to the emergence of electrical cyber-physical systems (ECPSs). However, the massive application of communication technologies makes the power grids become more vulnerable to cyber attacks. In this paper, we study the vulnerability of ECPSs and develop defence strategies against cyber attacks. Detection and protection algorithms are proposed to deal with the emergency of cascading failures. Moreover, we propose a weight adjustment strategy to solve the unbalanced power flows problem which is caused by splitting incidents. A MATLAB-based platform with advantages of easy programming, fast calculation, and no damage to systems is built for the offline simulation and analysis of the vulnerability of ECPSs. We also propose a five-aspect method of vulnerability assessment which includes the robustness, economic costs, degree of damage, vulnerable equipment, and trip point. The study is of significance to decision makers as they can get specific advice and defence strategies about a special power system.

In cyclic pursuit a platoon of vehicles are coupled in a unidirectional ring at the interaction level according to some control scheme. In the paper, a new cyclic pursuit control law is proposed, where each vehicle's linear speed and angular speed are proportional to the projection of its prey's position on its forward direction and lateral direction respectively. Through these interactions a cooperative behavior emerges and vehicles in the platoon eventually move at a constant speed on a circle with constant inter-vehicle spacings. The control scheme ensures ultimate boundedness and leads to only two stable equilibrium polygons. This contrasts with other cyclic pursuit control schemes, where vehicles may diverge to infinity and there are more stable equilibrium polygons as the total number of vehicles increases. For this control scheme, ultimate boundedness is proved using the pseudo-linearization technique. Possible equilibrium polygons are analyzed and stability and convergence properties are established through root locus analysis of a complex characteristic polynomial. Design rules are discussed, showing how the radius of the circle they converge to is controlled by an appropriate choice of control parameters.