MXene-Based Soft Humidity-Driven Actuator with High Sensitivity and Fast Response.

Soft actuators possessing notable mechanical deformations, high sensitivity, and fast response speed play a crucial role in various applications, such as artificial muscles, soft robots, and intelligent devices. In this study, a smart humidity-driven actuator was successfully fabricated by utilizing MXene/cellulose nanofiber (CNF)/LiCl (MCL) through vacuum-assisted filtration with fast response speed and high sensitivity. Utilizing the excellent humidity responsiveness of MXene/CNF and the robust hygroscopicity of LiCl, the synergistic effect of these materials enhances the hygroscopic properties and response speed of the actuator. The MCL actuator demonstrates excellent actuation performance, fast deformation, and reliable cyclic stability. To illustrate the extensive potential of the soft actuator, a range of applications, from bionic devices to soft grippers and crawling actuators, are showcased. Remarkably, the crawling actuator demonstrates sustained crawling motion without necessitating a humidity switch, relying on the humidity gradient from water droplets, and exhibits spontaneous directional motions within a certain range, which makes it a promising prospect in the field of soft robotics.

LM-Gel Plasticine Based on Binary Cooperative with Kneadable Shaping and Conductivity.

Liquid metal (LM)-based polymers have received growing interest for wearable health monitoring, electronic skins, and soft robotics. However, fabricating multifunctional LM-based polymers, in particular, featuring a convenient shaping ability while offering excellent deformability and conductivity remains a challenge. To overcome this obstacle, here, we propose a strategy to prepare LM-Gel "plasticine" (LGP) with great deformability, which is composed of a PVA (poly(vinyl alcohol)) soft network and an LM conductive phase. LGP can be easily constructed into different shapes such as plasticine and can be applied to different conditions (such as building a 3D circuit, circuit repair, and switch). Meanwhile, LGP has great conductivity (2.3 × 104 S/m) after surface annealing. Besides, LGP has a good electric heating performance, which shows the potential for application in wearable heating devices. Thus, this approach not only provides a way to prepare LM-polymer plasticine but also provides a novel perspective toward extending the applied range of LM-polymer composites.

Unveiling the roles of Sertoli cells lineage differentiation in reproductive development and disorders: a review.

In mammals, gonadal somatic cell lineage differentiation determines the development of the bipotential gonad into either the ovary or testis. Sertoli cells, the only somatic cells in the spermatogenic tubules, support spermatogenesis during gonadal development. During embryonic Sertoli cell lineage differentiation, relevant genes, including WT1, GATA4, SRY, SOX9, AMH, PTGDS, SF1, and DMRT1, are expressed at specific times and in specific locations to ensure the correct differentiation of the embryo toward the male phenotype. The dysregulated development of Sertoli cells leads to gonadal malformations and male fertility disorders. Nevertheless, the molecular pathways underlying the embryonic origin of Sertoli cells remain elusive. By reviewing recent advances in research on embryonic Sertoli cell genesis and its key regulators, this review provides novel insights into sex determination in male mammals as well as the molecular mechanisms underlying the genealogical differentiation of Sertoli cells in the male reproductive ridge.

Identifying gray matter alterations in Cushing's disease using machine learning: An interpretable approach.

BACKGROUND: Cushing's Disease (CD) is a rare clinical syndrome characterized by excessive secretion of adrenocorticotrophic hormone, leading to significant functional and structural brain alterations as observed in Magnetic Resonance Imaging (MRI). While traditional statistical analysis has been widely employed to investigate these MRI changes in CD, it has lacked the ability to predict individual-level outcomes. PURPOSE: To address this problem, this paper has proposed an interpretable machine learning (ML) framework, including model-level assessment, feature-level assessment, and biology-level assessment to ensure a comprehensive analysis based on structural MRI of CD. METHODS: The ML framework has effectively identified the changes in brain regions in the stage of model-level assessment, verified the effectiveness of these altered brain regions to predict CD from normal controls in the stage of feature-level assessment, and carried out a correlation analysis between altered brain regions and clinical symptoms in the stage of biology-level assessment. RESULTS: The experimental results of this study have demonstrated that the Insula, Fusiform gyrus, Superior frontal gyrus, Precuneus, and the opercular portion of the Inferior frontal gyrus of CD showed significant alterations in brain regions. Furthermore, our study has revealed significant correlations between clinical symptoms and the frontotemporal lobes, insulin, and olfactory cortex, which also have been confirmed by previous studies. CONCLUSIONS: The ML framework proposed in this study exhibits exceptional potential in uncovering the intricate pathophysiological mechanisms underlying CD, with potential applicability in diagnosing other diseases.

Attack-resilient fault detection for interconnected systems under DoS attack.

In light of the expanding cyber-space applications, the imperative consideration of cyber-attack ramifications on system security is evident. This paper presents a resilient dynamic event-triggered fault detection scheme for a class of nonlinear interconnected systems subjected to denial of service (DoS) attacks. To counteract multifaceted threats, the co-design challenge involving switched-type fault detection filters and a resilient dynamic event-triggered transmission mechanism is addressed. In the design phase of the filters, the frequency information of the signal is considered comprehensively and linear solvable conditions ensuring desired augment system performance are delineated. Through a series of comparative simulation experiments, the findings support the conclusion that the proposed attack-tolerant fault detection mechanism not only conserves network resources but also demonstrates superior detection capabilities for specific frequency fault signals.

Miniaturized and untethered McKibben muscles based on photothermal-induced gas-liquid transformation.

Pneumatic artificial muscles can move continuously under the power support of air pumps, and their flexibility also provides the possibility for applications in complex environments. However, in order to achieve operation in confined spaces, the miniaturization of artificial muscles becomes crucial. Since external attachment devices greatly hinder the miniaturization and use of artificial muscles, we propose a light-driven approach to get rid of these limitations. In this study, we report a miniaturized fiber-reinforced artificial muscle based on mold editing, capable of bending and axial elongation using gas-liquid conversion in visible light. The minimum volume of the artificial muscle prepared using this method was 15.7 mm3 (d = 2 mm, l = 5 mm), which was smaller than those of other fiber-reinforced pneumatic actuators. This research can promote the development of non-tethered pneumatic actuators for rescue and exploration, and create the possibility of miniaturization of actuators.

Clinical study on laparoscopic minimally invasive surgery and transumbilical single-port laparoscopic surgery in the treatment of benign ovarian tumours and its influence on ovarian functions.

OBJECTIVE: The objective of this study was to explore the influence of traditional laparoscopic surgery and transumbilical single-port laparoscopic surgery on ovarian function in patients with benign ovarian tumours. MATERIALS AND METHODS: Forty-four patients with benign ovarian tumours who were treated in our hospital from January 2020 to June 2021 were selected and randomly divided into two groups, with 22 cases in each group according to random number table. The conventional group was treated with conventional laparoscopic surgery, while the modified group was treated with transumbilical single-port laparoscopic surgery. The measurement method was t -test, and the enumeration method was two tests. The clinical operation-related indicators, ovarian function (follicle-stimulating hormone, E 2 and luteinising hormone), complication incidence, Visual Analogue Scale (VAS) and landscaping satisfaction scores of the two groups were compared. RESULTS: There were no significant differences in complications and operation duration between the two groups ( P > 0.05). After treatment, the ovarian function indexes and beautification satisfaction scores of the modified group were significantly superior to those of the conventional group ( P < 0.05). Besides, the intraoperative bleeding volume, post-operative exhaust time, hospital stay and three-dimensional VAS scores on day 1 and day 3 after surgery of the modified group were lower than those of the conventional group ( P < 0.05). CONCLUSION: Transumbilical single-port laparoscopic surgery for benign ovarian tumours has a significant clinical effect, which can effectively reduce bleeding during the operation, improve ovarian function, relieve surgical pain, promote rapid post-operative recovery and improve patients' satisfaction with landscaping. It is worthy of clinical application.

Hippocampal proteomic changes in high-fat diet-induced obese mice associated with memory decline.

Substantial evidence suggest that chronic consumption of high-fat diets (HFDs) can lead to obesity, abnormal metabolism, as well as cognitive impairment. Molecular and cellular changes regarding hippocampal dysfunctions have been identified in multiple HFD animal models. Therefore, in-depth identification of expression changes of hippocampal proteins is critical for understanding the mechanism of HFD-induced cognitive deficits. In this study, we fed 3-week-old male mice with HFD for 3 months to generate obese mice who exhibit systemic metabolic abnormality and learning and memory decline. Using an iTRAQ-labeled proteomic analysis, we identified a total of 82 differentially expressed proteins (DEPs) in the hippocampus upon HFD with 35 up-regulated proteins and 47 down-regulated proteins. Functional enrichment indicated that these DEPs were predominantly enriched in regulation of catabolic process, dendritic shaft, neuron projection morphogenesis and GTPase regulator activity. Protein-protein interaction enrichment showed that the DEPs are mostly enriched in postsynaptic functions; and of them, six proteins (i.e., DLG3, SYNGAP1, DCLK1, GRIA4, GRIP1, and ARHGAP32) were involved in several functional assemblies of the postsynaptic density including G-protein signaling, scaffolding and adaptor, kinase and AMPA signaling, respectively. Collectively, our findings suggest that these DEPs upon HFD might contribute to memory decline by disturbing neuronal and postsynaptic functions in the hippocampus.

Identification of the AP2/ERF transcription factor family of Eleutherococcus senticosus and its expression correlation with drought stress.

In this study, through analysis of the genome of Eleutherococcus senticosus (ES). 228 AP2/ERF genes were identified and classified into 5 groups AP2 (47 genes), ERF (108 genes), RAV (6 genes), DREB (64 genes), and soloist (3 genes). According to the AP2/ERF classification of Arabidopsis thaliana, the ES AP2/ERF proteins were subdivided into 15 groups. The gene structure and motifs of each group of AP2/ERF in ES were highly similar, which confirmed the conservation of AP2/ERF genes. The ES AP2/ERF genes were unevenly distributed on chromosomes, and a total of four pairs of tandem repeats, and 84 co-linear gene pairs were found, so the AP2/ERF genes expanded in a fragment replication manner, and dominated by pure selection during evolution. By analyzing the transcriptome data of ES under different drought stress conditions, 87 AP2/ERF genes with differential expression were obtained, of which 10 genes with highly significant differences were further analyzed and screened for qRT-PCR validation. To the best of our knowledge, this is the first report on the AP2/ERF gene of Eleutherococcus senticosus, and the bioinformatics analysis and experimental validation provided valuable information about them, which is of great significance for further research on the molecular mechanisms of ES in response to drought stress.

The mechanical, optical, and thermal properties of graphene influencing its pre-clinical use in treating neurological diseases.

Rapid progress in nanotechnology has advanced fundamental neuroscience and innovative treatment using combined diagnostic and therapeutic applications. The atomic scale tunability of nanomaterials, which can interact with biological systems, has attracted interest in emerging multidisciplinary fields. Graphene, a two-dimensional nanocarbon, has gained increasing attention in neuroscience due to its unique honeycomb structure and functional properties. Hydrophobic planar sheets of graphene can be effectively loaded with aromatic molecules to produce a defect-free and stable dispersion. The optical and thermal properties of graphene make it suitable for biosensing and bioimaging applications. In addition, graphene and its derivatives functionalized with tailored bioactive molecules can cross the blood-brain barrier for drug delivery, substantially improving their biological property. Therefore, graphene-based materials have promising potential for possible application in neuroscience. Herein, we aimed to summarize the important properties of graphene materials required for their application in neuroscience, the interaction between graphene-based materials and various cells in the central and peripheral nervous systems, and their potential clinical applications in recording electrodes, drug delivery, treatment, and as nerve scaffolds for neurological diseases. Finally, we offer insights into the prospects and limitations to aid graphene development in neuroscience research and nanotherapeutics that can be used clinically.

Quantitative analysis of the current status and research trends of biochar research - A scientific bibliometric analysis based on global research achievements from 2003 to 2023.

Biochar has excellent physical and chemical properties such as porosity, high carbon content, high cation exchange capacity, and rich surface functional groups and has been widely used in environmental remediation. Over the past 20 years, although various reviews have described the application of biochar as an environmentally friendly multifunctional material in environmental remediation, no comprehensive summary and analysis of the research trends in this field exists. To promote the rapid and stable development of the field of biochar, the current state of research on biochar is clarified using the bibliometric method in this report, and potential development directions and challenges for the future are identified. All relevant biochar literature from 2003-2023 was collected from the Chinese National Knowledge Infrastructure and Web of Science Core Collection. A total of 6,119 published Chinese papers and 25,174 English papers were selected for the quantitative analysis. CiteSpace, VOSviewer, and Scimago graphics software was used to summarize the numbers of papers published over the years, as well as the countries, institutions, and authors that published the most articles. Secondly, using keyword co-occurrence and emergence analysis, the recognized research hotspots in different areas such as adsorbents, soil remediation, catalytic oxidation, supercapacitors, and "biochar-microbial" synergy were analyzed. Finally, the prospects and challenges of biochar were assessed to provide new perspectives for further promoting its development in technological, economic, environmental, and other aspects.

Effect of tinnitus on sound localization ability in patients with normal hearing

Abstract Objectives To determine whether tinnitus negatively impacts the accuracy of sound source localization in participants with normal hearing. Methods Seventy-five participants with tinnitus and 74 without tinnitus were enrolled in this study. The accuracy of sound source discrimination on the horizontal plane was compared between the two participant groups. The test equipment consisted of 37 loudspeakers arranged in a 180° arc facing forward with 5° intervals between them. The stimuli were pure tones of 0.25, 0.5, 1, 2, 4, and 8 kHz at 50 dB SPL. The stimuli were divided into three groups: low frequency (LF: 0.25, 0.5, and 1 kHz), 2 kHz, and high frequency (HF: 4 and 8 kHz) stimuli. Results The Root Mean Square Error (RMSE) score of all the stimuli in the tinnitus group was significantly higher than that in the control group (13.45 ± 3.34 vs. 11.44 ± 2.56, p = 4.115, t < 0.001). The RMSE scores at LF, 2 kHz, and HF were significantly higher in the tinnitus group than those in the control group (LF: 11.66 ± 3.62 vs. 10.04 ± 3.13, t = 2.918, p = 0.004; 2 kHz: 16.63 ± 5.45 vs. 14.43 ± 4.52, t = 2.690, p = 0.008; HF: 13.42 ± 4.74 vs. 11.14 ± 3.68, t = 3.292, p = 0.001). Thus, the accuracy of sound source discrimination in participants with tinnitus was significantly worse than that in those without tinnitus, despite the stimuli frequency. There was no difference in the ability to localize the sound of the matched frequency and other frequencies (12.86 ± 6.29 vs. 13.87 ± 3.14, t = 1.204, p = 0.236). Additionally, there was no correlation observed between the loudness of tinnitus and RMSE scores (r = 0.096, p = 0.434), and the Tinnitus Handicap Inventory (THI) and RMSE scores (r = −0.056, p = 0.648). Conclusions Our present data suggest that tinnitus negatively impacted sound source localization accuracy, even when participants had normal hearing. The matched pitch and loudness and the impact of tinnitus on patients' daily lives were not related to the sound source localization ability. Level of evidence 4.

The interference of tinnitus on sound localization was related to the type of stimulus.

Spatial processing is a major cognitive function of hearing. Sound source localization is an intuitive evaluation of spatial hearing. Current evidence of the effect of tinnitus on sound source localization remains limited. The present study aimed to investigate whether tinnitus affects the ability to localize sound in participants with normal hearing and whether the effect is related to the type of stimulus. Overall, 40 participants with tinnitus and another 40 control participants without tinnitus were evaluated. The sound source discrimination tasks were performed on the horizontal plane. Pure tone (PT, with single frequency) and monosyllable (MS, with spectrum information) were used as stimuli. The root-mean-square error (RMSE) score was calculated as the mean target response difference. When the stimuli were PTs, the RMSE scores of the control and tinnitus group were 11.77 ± 2.57° and 13.97 ± 4.18°, respectively. The control group performed significantly better than did the tinnitus group (t = 2.841, p = 0.006). When the stimuli were MS, the RMSE scores of the control and tinnitus groups were 7.12 ± 2.29° and 7.90 ± 2.33°, respectively. There was no significant difference between the two groups (t = 1.501, p = 0.137). Neither the effect of unilateral or bilateral tinnitus (PT: t = 0.763, p = 0.450; MS: t = 1.760, p = 0.086) nor the effect of tinnitus side (left/right, PT: t = 0.389, p = 0.703; MS: t = 1.407, p = 0.179) on sound localization ability were determined. The sound source localization ability gradually deteriorated with an increase in age (PT: r2 = 0.153, p < 0.001; MS: r2 = 0.516, p = 0.043). In conclusion, tinnitus interfered with the ability to localize PTs, but the ability to localize MS was not affected. Therefore, the interference of tinnitus in localizing sound sources is related to the type of stimulus.

Genome-wide identification of MBD gene family members in Eleutherococcus senticosus with their expression motifs under drought stress and DNA demethylation.

BACKGROUND: Methyl-binding domain (MBD) is a class of methyl-CpG-binding domain proteins that affects the regulation of gene expression through epigenetic modifications. MBD genes are not only inseparable from DNA methylation but have also been identified and validated in various plants. Although MBD is involved in a group of physiological processes and stress regulation in these plants, MBD genes in Eleutherococcus senticosus remain largely unknown. RESULTS: Twenty EsMBD genes were identified in E. senticosus. Among the 24 chromosomes of E. senticosus, EsMBD genes were unevenly distributed on 12 chromosomes, and only one tandem repeat gene existed. Collinearity analysis showed that the fragment duplication was the main motif for EsMBD gene expansion. As the species of Araliaceae evolved, MBD genes also evolved and gradually exhibited different functional differentiation. Furthermore, cis-acting element analysis showed that there were numerous cis-acting elements in the EsMBD promoter region, among which light response elements and anaerobic induction elements were dominant. The expression motif analysis revealed that 60% of the EsMBDs were up-regulated in the 30% water content group. CONCLUSIONS: By comparing the transcriptome data of different saponin contents of E. senticosus and integrating them with the outcomes of molecular docking analysis, we hypothesized that EsMBD2 and EsMBD5 jointly affect the secondary metabolic processes of E. senticosus saponins by binding to methylated CpG under conditions of drought stress. The results of this study laid the foundation for subsequent research on the E. senticosus and MBD genes.

Effect of tinnitus on sound localization ability in patients with normal hearing.

OBJECTIVES: To determine whether tinnitus negatively impacts the accuracy of sound source localization in participants with normal hearing. METHODS: Seventy-five participants with tinnitus and 74 without tinnitus were enrolled in this study. The accuracy of sound source discrimination on the horizontal plane was compared between the two participant groups. The test equipment consisted of 37 loudspeakers arranged in a 180° arc facing forward with 5° intervals between them. The stimuli were pure tones of 0.25, 0.5, 1, 2, 4, and 8kHz at 50dB SPL. The stimuli were divided into three groups: low frequency (LF: 0.25, 0.5, and 1kHz), 2kHz, and high frequency (HF: 4 and 8kHz) stimuli. RESULTS: The Root Mean Square Error (RMSE) score of all the stimuli in the tinnitus group was significantly higher than that in the control group (13.45±3.34 vs. 11.44±2.56, p=4.115, t<0.001). The RMSE scores at LF, 2kHz, and HF were significantly higher in the tinnitus group than those in the control group (LF: 11.66±3.62 vs. 10.04±3.13, t=2.918, p=0.004; 2kHz: 16.63±5.45 vs. 14.43±4.52, t=2.690, p=0.008; HF: 13.42±4.74 vs. 11.14 ±3.68, t=3.292, p=0.001). Thus, the accuracy of sound source discrimination in participants with tinnitus was significantly worse than that in those without tinnitus, despite the stimuli frequency. There was no difference in the ability to localize the sound of the matched frequency and other frequencies (12.86±6.29 vs. 13.87±3.14, t=1.204, p=0.236). Additionally, there was no correlation observed between the loudness of tinnitus and RMSE scores (r=0.096, p=0.434), and the Tinnitus Handicap Inventory (THI) and RMSE scores (r=-0.056, p=0.648). CONCLUSIONS: Our present data suggest that tinnitus negatively impacted sound source localization accuracy, even when participants had normal hearing. The matched pitch and loudness and the impact of tinnitus on patients' daily lives were not related to the sound source localization ability.

Design, synthesis and biological evaluation of novel 9-methyl-9H-purine and thieno[3, 2-d]pyrimidine derivatives as potent mTOR inhibitors.

The mammalian target of rapamycin (mTOR) has been proved to be an effective target for cancer therapy. Two kinds of mTOR inhibitors, the rapalogs and mTOR kinase inhibitors (TORKi), have been developed and clinically validated in several types of malignancies. Compared with rapalogs, TORKi can exert better antitumor activity by inhibiting both mTORC1 and mTORC2, but the clinical development of current TORKi candidates has been relative slow, more TORKi with novel scaffold need to be developed to expand the current pipelines. In this study, a series of 9-methyl-9H-purine and thieno[3, 2-d]pyrimidine derivatives were designed, synthesized and biological evaluation. Most of these compounds exhibited good mTOR kinase inhibitory activity and selectivity over PI3Kα. Subsequent antiproliferative assay allowed us to identify the lead compound 15i, which display nanomolar to low micromolar IC50s against six human cancer cell lines. 15i could induce cell cycle arrest of MCF-7, PC-3 and A549 cells at the G0/G1 phase and suppress the migration and invasion of these cancer cells by suppressing the phosphorylation of AKT and P70S6 kinase. It could also regulate autophagy-related proteins to induce autophagy. Therefore, 15i would be a starting point for the development of new TORKi as anticancer drug.

Proteome profiling of the prefrontal cortex of Fmr1 knockout mouse reveals enhancement of complement and coagulation cascades.

Fragile X mental retardation protein (FMRP) deficit resulted from mutations in its encoded fragile X mental retardation 1 (Fmr1) gene is a common inherited cause of Fragile X syndrome (FXS) characterized by intellectual disability and autism spectrum disorder (ASD). The FMRP absence-induced altered gene expression in prefrontal cortex (PFC) are associated with autistic behaviors. However, there lacks a large-scale protein profiling in the PFC upon loss of FMRP. This study used a TMT-labeled proteomic analysis to identify a protein profile of the PFC in the Fmr1 knockout mouse. A total of 5886 proteins were identified in the PFC with 100 differentially abundant proteins (DAPs) in response to FMRP deficiency. Bioinformatical analyses showed that these DAPs were mostly enriched in immune system, extracellular part and complement and coagulation cascades. The complement and coagulation cascades include 6 upregulated proteins (SERPING1, C1QA, C3, FGA, FGB and FGG), which are associated with fibrin degradation, cell lysis, degranulation chemotaxis and phagocytosis linked to activation of immune and inflammatory responses. Thus, our data provide an altered protein profile upon loss of FMRP in the PFC, and suggest that the enhancement of complement and coagulation cascades might contribute to etiological and pathogenic roles of ASD in FXS. SIGNIFICANCE: The etiology of autism spectrum disorder (ASD), a group of neurobiological disorders characterized by deficits in social interaction barriers and other abnormal behaviors, is still elusive. Autistic-like phenotypes are present in both Fragile X syndrome (FXS) patients and FMRP-deficiency FXS models. Given that prefrontal cortex is a critical brain area for social interaction, the FMRP absence induced-changes of a subset of proteins might contribute to ASD in FXS. Using a comprehensive proteomic analysis, this study provides a prefrontal protein profile of the FMRP-absent mouse with a total of 100 differentially abundant proteins (DAPs). Bioinformatic analyses suggest that these DAPs are mainly involved in the regulations of immune system and complement and coagulation cascades. We also show that 6 upregulated proteins (SERPING1, C1QA, C3, FGA, FGB and FGG) in the complement and coagulation cascades are associated with fibrin degradation, cell lysis, degranulation chemotaxis and phagocytosis regarding dysregulation of immune and inflammatory responses in the prefrontal cortex. Therefore, this study suggests that these FMRP-deficient DAPs in the prefrontal cortex might contribute to the etiology and pathogenesis of ASD in FXS.

Distributed Fault-Tolerant Containment Control Protocols for the Discrete-Time Multiagent Systems via Reinforcement Learning Method.

This article investigates the model-free fault-tolerant containment control problem for multiagent systems (MASs) with time-varying actuator faults. Depending on the relative state information of neighbors, a distributed containment control method based on reinforcement learning (RL) is adopted to achieve containment control objective without prior knowledge on the system dynamics. First, based on the information of agent itself and its neighbors, a containment error system is established. Then, the optimal containment control problem is transformed into an optimal regulation problem for the containment error system. Furthermore, the RL-based policy iteration method is employed to deal with the corresponding optimal regulation problem, and the nominal controller is proposed for the original fault-free system. Based on the nominal controller, a fault-tolerant controller is further developed to compensate for the influence of actuator faults on MAS. Meanwhile, the uniform boundedness of the containment errors can be guaranteed by using the presented control scheme. Finally, numerical simulations are given to show the effectiveness and advantages of the proposed method.

Event-Triggered Multigradient Recursive Reinforcement Learning Tracking Control for Multiagent Systems.

In this article, the tracking control problem of event-triggered multigradient recursive reinforcement learning is investigated for nonlinear multiagent systems (MASs). Attention is focused on the distributed reinforcement learning approach for MASs. The critic neural network (NN) is applied to estimate the long-term strategic utility function, and the actor NN is designed to approximate the uncertain dynamics in MASs. The multigradient recursive (MGR) strategy is tailored to learn the weight vector in NN, which eliminates the local optimal problem inherent in gradient descent method and decreases the dependence of initial value. Furthermore, reinforcement learning and event-triggered mechanism can improve the energy conservation of MASs by decreasing the amplitude of the controller signal and the controller update frequency, respectively. It is proved that all signals in MASs are semiglobal uniformly ultimately bounded (SGUUB) according to the Lyapunov theory. Simulation results are given to demonstrate the effectiveness of the proposed strategy.