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The paper is concerned with the region tracking control problem of multiple nonholonomic mobile robot systems with collision avoidance. The peculiar characteristic of the proposed scheme is that a class of potential energy functions is chosen to form the desired target region constraining the robots for aggregation, and some local potential energy functions are selected to maintain collision avoidance among robots. Such that each mobile robot only needs to interact with their neighbors to realize the region tracking control task. Moreover, this paper provides a new analytical framework of region tracking control for a network of wheeled mobile robots, in which the integration of the system decomposition and sliding mode control method enables to convert the nonholonomic constraint problem of the controlled mobile robot system into a holonomic constraint problem. This provides a new approach to solving the mobile robot control problem. Theoretical analysis and numerical simulation results are given to validate the effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

As digital communication and storage continue to expand, the protection of image privacy information becomes increasingly critical. To safeguard sensitive visual information from unauthorized access, this paper proposes a novel image encryption scheme that integrates multiobjective Artificial Bee Colony (ABC) optimization algorithm and DNA coding. Multiple evaluation metrics including correlation relationship, Number of Pixel Change Rate (NPCR), Unified Average Changing Intensity (UACI), and information entropy are collaboratively optimized by the ABC algorithm. The proposed method begins with the application of the SHA-256 algorithm to generate keys and random sequences using chaotic systems. These sequences are then employed for shuffling, DNA coding, decoding, and diffusion, generating initial encrypted images. Subsequently, the encrypted images serve as individuals within the ABC algorithm to determine optimal parameters of the chaotic systems and the best ciphertext image. Simulation experiments demonstrate that the ciphertext images achieved excellent results in information entropy, pixel correlation coefficient, NPCR, and UACI. The integration of the multiobjective ABC optimization algorithm with DNA coding in our proposed image encryption scheme results in heightened security, as evidenced by superior performance in various metrics. [ABSTRACT FROM AUTHOR]

The emerging physical-layer unclonable attribute-aided authentication (PLUA) schemes are capable of outperforming traditional isolated approaches, with the advantage of having reliable fingerprints. However, conventional PLUA methods face new challenges in artificial intelligence of things (AIoT) applications owing to their limited flexibility. These challenges arise from the distributed nature of AIoT devices and the involved information, as well as the requirement for short end-to-end latency. To address these challenges, we propose a security authentication scheme that utilizes intelligent prediction mechanisms to detect spoofing attack. Our approach is based on a dynamic authentication method using long short term memory (LSTM), where the edge computing node observes and predicts the time-varying channel information of access devices to detect clone nodes. Additionally, we introduce a Savitzky–Golay filter-assisted high order cumulant feature extraction model (SGF-HOCM) for preprocessing channel information. By utilizing future channel attributes instead of relying solely on previous channel information, our proposed approach enables authentication decisions. We have conducted extensive experiments in actual industrial environments to validate our prediction-based security strategy, which has achieved an accuracy of 97%. [ABSTRACT FROM AUTHOR]

SUMMARY: This paper proposes a fully distributed continuous region-reaching controller for multi-robot systems which can effectively eliminate the chattering issues and the negative effects caused by discontinuities. The adaptive control gain technique is employed to solve the distributed region-reaching control problem. By performing Lyapunov function-based stability analysis, it is shown that all the robots can move cohesively within the desired region under the proposed distributed control algorithm. In addition, collision avoidance and velocity matching within the moving region can be guaranteed under properly designed control gains. Simulation examples are given to verify the capabilities of the proposed control method. [ABSTRACT FROM AUTHOR]

This paper presents a novel deoxyribonucleic acid (DNA) network encryption method combined with a hyperchaotic system for image encryption. The DNA network encryption algorithm contains 12 different DNA operations, which overcomes the limitations of existing DNA encryption schemes that rely on limited fixed DNA operation types. Firstly, secure hash algorithm 256-bit (SHA-256) is employed to generate secret keys associated with the plaintext. Secondly, the hyperchaotic system is employed to derive key streams with high plaintext sensitivity. Thirdly, the DNA encoding, DNA network encryption and decoding are performed sequentially to encrypt the plaintext image using the keystreams. Finally, an additional row–column disruption is executed to strengthen the resistance of the encryption scheme to attacks. Security analysis reveals that the information entropy of our cipher image reaches 7.9975 and the average pixel correlation coefficients are below 0.01, implying that our encryption algorithm has excellent security. [ABSTRACT FROM AUTHOR]

This paper addresses the cooperative adaptive consensus tracking for a group of multiple nonholonomic mobile robots, where the nonholonomic robot model is assumed to be a canonical vehicle having two actuated wheels and one passive wheel. By integrating a kinematic controller and a torque controller for the nonholonomic robotic system, a cooperative adaptive consensus tracking strategy is developed for the uncertain dynamic models using Lyapunov-like analysis in combination with backstepping approach and sliding mode technique. A key feature of the developed adaptive consensus tracking algorithm is the introduction of a directed network topology into the control constraints based on algebraic graph theory to characterise the communication interaction among robots, which plays an important role in realising the cooperative consensus tracking with respect to a specific common reference trajectory. Furthermore, a novel framework is proposed for developing a unified methodology for the convergence analysis of the closed-loop control systems, which can fully ensure the desired adaptive consensus tracking for multiple nonholonomic mobile robots. Subsequently, illustrative examples and numerical simulations are provided to demonstrate and visualise the theoretical results. [ABSTRACT FROM AUTHOR]

Abstract This paper is concerned with the multi-objective region reaching control for a swarm of robots which are formulated by Lagrangian dynamics. Two distributed multi-objective region reaching control protocols are proposed for the networked robotic systems under directed acyclic topology, and a unifying methodology is presented to perform the convergence analysis for the robotic systems with static and moving target regions. The control strategy is developed by using the potential energy function approach, and the specified shapes of the various desired regions are constructed by selecting appropriate objective functions. In this control strategy, a network of a large number of robots evolves into multiple groups, and the robots in each group only require communicating with their neighbors. Thus, the proposed control strategy is effective for multi-objective region reaching control for a swarm of robots in practical applications. Finally, simulation examples are given to show the validity of the theoretical results., [ABSTRACT FROM AUTHOR]

Abstract This study is concerned with the region reaching formation control problem with collision and obstacle avoidance for multi-robot systems in the presence of model uncertainties and external disturbances. A novel neural network based robust control scheme combining with the adaptive compensator and the adaptive control gain is proposed to achieve the region reaching formation control with collision and obstacle avoidance. It is shown that under the proposed control method, all the robots can always reach into the objective region, maintain their formation, and guarantee collision and obstacle avoidance. Illustrative examples are presented to show the effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

The enzymatic hydrolysis conditions of tobacco flower buds under the action of cellulase, hemicellu-lase, pectinase and protease were optimized by orthogonal test. The flavor components were extracted by Mail-lard reaction and simultaneous distillation extraction. The extracted aroma components were analyzed by GC-MS. The results showed that 1) the enzymatic hydrolysis temperature was 50 °C, the enzymatic hydrolysis time was 6 h, the enzymatic hydrolysis pH was 6, and the enzyme content was 1 % ( mass fraction), the amino acid content and reducing sugar content were the highest, respectively 2. 89 mgg and 0. 88 mg/g. 2) There were mainly 65 kinds of aroma substances, including myristic acid, dihydro kiwi lactone, oxidized carbenene, tobacco alkene, phytonone, damasthone, giant bean ketone, oleic acid amide, 2-n-pentyl group. The low aroma threshold such as furan in these substances was a key aroma substance in tobacco and contributed to tobacco aroma. 3 ) The correlation between amino acid and reducing sugar content and the total amount of aroma substances was not obvious, and it was positively correlated with the number of aroma substances. [ABSTRACT FROM AUTHOR]

This study addresses the problem of formation control with collision avoidance for networked Lagrangian systems with uncertain parameters interacting on directed network communication topologies. Two adaptive formation control strategies with collision avoidance are proposed by making use of adaptive gain techniques for both cases of with and without a dynamic leader. The main objective of the proposed control strategies is to dispatch a group of agents to maintain a desired geometric pattern, while still guarantee collision avoidance at any time, and eventually to achieve velocity matching. A distinctive feature of the developed adaptive gain is to adapt itself duly based on both the network communication topology and collision avoidance constraints, so it is feasible to be implemented in practice. Some general criteria are derived to guarantee that the desired formation with collision avoidance for the networked Lagrangian systems can be achieved. Finally, numerical simulations are given to show the performance of the proposed control methodologies. [ABSTRACT FROM AUTHOR]

In this work, some new oscillation criteria are established for a second-order nonlinear mixed neutral differential equation with distributed deviating arguments. Several examples are also provided to illustrate these results. [ABSTRACT FROM AUTHOR]

Cell cycle dysregulation is a defining feature of breast cancer. Here, 1‐methyl‐nicotinamide (1‐MNA), metabolite of nicotinamide N‐methyltransferase(NNMT) is identified, as a novel driver of cell‐cycle progression in breast cancer. NNMT, highly expressed in breast cancer tissues, positively correlates with tumor grade, TNM stage, Ki‐67 index, and tumor size. Ablation of NNMT expression dramatically suppresses cell proliferation and causes cell‐cycle arrest in G0/G1 phase. This phenomenon predominantly stems from the targeted action of 1‐MNA, resulting in a specific down‐regulation of p27 protein expression. Mechanistically, 1‐MNA expedites the degradation of p27 proteins by enhancing cullin‐1 neddylation, crucial for the activation of Cullin‐1‐RING E3 ubiquitin ligase(CRL1)—an E3 ubiquitin ligase targeting p27 proteins. NNMT/1‐MNA specifically up‐regulates the expression of UBC12, an E2 NEDD8‐conjugating enzyme required for cullin‐1 neddylation. 1‐MNA showes high binding affinity to UBC12, extending the half‐life of UBC12 proteins via preventing their localization to lysosome for degradation. Therefore, 1‐MNA is a bioactive metabolite that promotes breast cancer progression by reinforcing neddylation pathway‐mediated p27 degradation. The study unveils the link between NNMT enzymatic activity with cell‐cycle progression, indicating that 1‐MNA may be involved in the remodeling of tumor microenvironment. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to advance the concept of region reaching control for a single robot to the study of region reaching consistency for uncertain fully‐actuated multi‐robot systems formulated by Lagrange dynamics. By introducing a directed network communication topology and utilizing the pinning‐like control methods, a distributed region reaching consensus control strategy is proposed. The desired region shape can be specified by selecting an appropriate potential objective function. A feature of the developed region reaching consensus algorithm is fully distributed, which is also an important generalization of pinning‐like set point tracking scheme based on the typical proportion‐integration‐differentiation control scheme. More importantly, the scope of consistency in this paper can be explicitly defined, which is different from traditional consistency control algorithms. Subsequently, numerical examples are presented to illustrate the performance of the designed controllers. [ABSTRACT FROM AUTHOR]

Controlling a robot manipulator system with both uncertain kinematics and dynamics is a challenging problem since the traditional control schemes that relying on the robot system models are no longer applicable. Developing a neural network‐based adaptive tracking control for such uncertain robot manipulator systems with region constraints is especially changing. In this paper, region tracking controllers are designed for a robot manipulator systems with uncertain kinematics and dynamics. The developed region tracking controllers ensures that the uncertain robot manipulator can track a moving region other than the traditional fixed point, which has better redundancy characteristics. The results are obtained through the development of the sliding‐mode and a novel proportion‐integration‐differentiation (PID)‐like method to address the region tracking control problem. Numerical simulations are presented to verify the proposed controller's performance. [ABSTRACT FROM AUTHOR]

Summary: Development in higher organisms requires proper gene silencing, partially achieved through trimethylation of lysine 27 on histone H3 (H3K27me3). However, how the normal distribution of this modification is established and maintained and how it affects gene expression remains unclear, especially in fungi. Polycomb repressive complex 2 (PRC2) catalyses H3K27me3 to assemble transcriptionally repressed facultative heterochromatin and is crucial in animals, plants, and fungi.Here, we report on the critical role of an additional PRC2 subunit in the normal distribution of H3K27me3 occupancy and the stable maintenance of gene repression in the rice fungal pathogen Magnaporthe oryzae. P55, identified as an additional PRC2 subunit, is physically associated with core subunits of PRC2 and is required for a complete level of H3K27me3 modification.Loss of P55 caused severe global defects in the normal distribution of H3K27me3 and transcriptional reprogramming on the H3K27me3‐occupied genes. Furthermore, we found that the Sin3 histone deacetylase complex was required to sustain H3K27me3 occupancy and stably maintain gene repression by directly interacting with P55.Our results revealed a novel mechanism by which P55 and Sin3 participate in the normal distribution of facultative heterochromatic modifications and the stable maintenance of gene repression in eukaryotes. [ABSTRACT FROM AUTHOR]

Purpose: To describe the rationale, the surgical technique, and the short-term follow-up results of a new minimally invasive treatment of osteonecrosis of the femoral head (ONFH) with an angioconductive bioceramic rod (ABR) implant.Methods: Sixty-two patients (72 hips) with ARCO stage IIA-IIIC ONFH treated with the minimally invasive ABR from January 2012 to December 2016 were reviewed (17 females, 45 males, mean age 44.49). This technique used the angioconductive properties of the porous implant to repair the necrosis by driving vascularization from the trochanter to the necrotic area. Patients had a mean follow-up period of 26.74 months. The outcomes were evaluated by hip joint survival, radiograph, and the Harris Hip Score (HHS). The complications occurred during the treatment period were recorded.Results: No serious post-operative complications occurred during the treatment. The overall joint survival rate was 90.27%, with seven conversions to THA. Improvements were observed in 23 (31.95%) hips, 24 (33.33%) hips remained stable, and 25 (34.72%) hips had worse results according to the radiographic evaluation. The mean HHS at the end follow-up significantly improved compared to the pre-operative mean HHS (82.27 vs 58.14, p < 0.001). In both radiographic evaluation and HHS, the treatment was more effective on patients beneath 44 years old (p < 0.05); ARCO stage II compared to stage III (p < 0.05); and China-Japan Friendship Hospital (CJFH) type C compared to CJFH type L (p < 0.05).Conclusions: The minimally invasive treatment of ONFH with ABR showed promising results in delaying or even terminating the progression of the necrosis and improving hip function, especially in younger patients and in the early stages of the disease. [ABSTRACT FROM AUTHOR]

Objective To explore a panel of serum biomarkers for laboratory diagnosis of pediatric Henoch-Schönlein purpura (HSP). Methods The blood white blood cells (WBC) and serum levels of serum amyloid A (SAA), interleukin 6 (IL-6), immunoglobulin A (IgA), immunoglobulin G (IgG), immunoglobulin M (IgM), immunoglobulin E (IgE), C-reactive protein (CRP), complement component 3 (C3), complement component 4 (C4), and ASO (anti-streptolysin O) were detected in 127 patients with Henoch-Schonlein purpura (HSP), 110 cases of septicemia patients, and 121 healthy volunteers. The diagnostic ability of biomarkers selected from HSP and septicemia patients was analyzed by ROC curve. By designing the calculation model, the biomarker index was calculated for laboratory diagnosis of HSP and differential diagnosis between HSP and septicemia. Results The levels of serum WBC, CRP, IL-6 and SAA in the septicemia patients were significantly higher than those in the control group (p < 0.05). Compared with the healthy individuals, serum levels of WBC, CRP, IL-6, SAA, IgA and IgM were significantly increased in patients with HSP (p < 0.05). The area under the curve (AUC) of SAA, IgA, IgM, WBC, IL-6, and CRP in the patients with HSP was 0.964, 0.855, 0.849, 0.787, 0.765, and 0.622, respectively. The values of SAA, IgA, IgM, WBC, IL-6, and CRP in septicemia patients were 0.700, 0.428, 0.689, 0.682, 0.891, and 0.853, respectively. Biomarker index = SAA + IgA / 4000 + IgM / 4000 × 0.4 CRP mean value CRP i . The biomarker index in HSP patients was significantly higher than that of the healthy controls. However, the biomarker index in septicemia patients was significantly lower than the control. Conclusion The biomarker index of HSP patients is higher than that of the control group. While in the infectious disease represented by septicemia, it is decreased. The detection of biomarker index could exclude the interference of infection as the auxiliary examination to HSP patients. [ABSTRACT FROM AUTHOR]

[Display omitted] The representative morphological features of pyroptosis are excessive cell swelling and subsequent membrane rupture. However, the mechanism underlying the cell's inherent inability to regulate volume during the progression of pyroptosis is poorly understood. In the current study, we found that both volume-activated chloride currents (I cl, vol) and the regulatory volume decrease (RVD) were markedly decreased in bone marrow–derived macrophages (BMDMs) undergoing pyroptosis induced by lipopolysaccharides (LPS) and nigericin. The inhibition of I Cl, vol and RVD by the chloride channel blockers, tamoxifen or DCPIB, led to the emergence of pyroptosis-like phenotypes such as activated-caspase-1, pyroptotic-body-like bubbles, and a fried-egg–like appearance. Moreover, the expression of the volume-activated chloride channel (VRAC) constituent protein Leucine-Rich Repeat-Containing 8A (LRRC8A) was significantly down-regulated in pyroptotic BMDMs treated with LPS and nigericin. The silencing of LRRC8A expression by small interfering RNA (si)-LRRC8A transfection not only reduced I Cl, vol and RVD, but also caused BMDMs to show pyroptosis-like manifestations such as activated-caspase-1, membrane bubbles, and have a fried-egg–like appearance. These results reveal a new mechanism for the loss of volume regulation in the process of pyroptotic cell swelling and strongly suggest that a functional deficiency of VRAC/LRRC8A plays a key role in this disorder. [ABSTRACT FROM AUTHOR]