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ABSTRACT In this article, an event‐triggered adaptive neural network controller based on threshold band is designed for a four wheels independently steered and four wheels independently driven (4WS4WD) mobile robot. The 4WS4WD mobile robot is attracting attention for its excellent motion performance such as manipulation versatility and posture flexibility. However, its control difficulty is increased due to its characteristics of being controlled by eight motors for steering and driving respectively. Also, since the robot itself has limited computing and communication resources, real‐time control cannot be guaranteed. To copy with that, the kinematic and dynamics models are first introduced for the 4WS4WD mobile robot. Second, an adaptive neural network controller with low‐frequency learning rate is utilized to control the mobile robot since there are unknown perturbations in the model. It can maintain system stability while handing unidentified model perturbations. The stability of the controller is demonstrated by Lyapunov stability analysis. An event‐triggered based on threshold band is suggested to lessen the amount of computation in the control process. Finally, the simulation outcomes further demonstrate how the suggested approach can greatly lessen the computational and communication cost while maintaining control performance. [ABSTRACT FROM AUTHOR]

The balance between ubiquitination and deubiquitination is instrumental in the regulation of protein stability and maintenance of cellular homeostasis. The deubiquitinating enzyme, ubiquitin-specific protease 36 (USP36), a member of the USP family, plays a crucial role in this dynamic equilibrium by hydrolyzing and removing ubiquitin chains from target proteins and facilitating their proteasome-dependent degradation. The multifaceted functions of USP36 have been implicated in various disease processes, including cancer, infections, and inflammation, via the modulation of numerous cellular events, including gene transcription regulation, cell cycle regulation, immune responses, signal transduction, tumor growth, and inflammatory processes. The objective of this review is to provide a comprehensive summary of the current state of research on the roles of USP36 in different pathological conditions. By synthesizing the findings from previous studies, we have aimed to increase our understanding of the mechanisms underlying these diseases and identify potential therapeutic targets for their treatment. [ABSTRACT FROM AUTHOR]

An adaptive neural network fault‐tolerant control method is proposed for the non‐affine multi‐agent systems with actuator failure and input saturation. Through the transformation of the original multi‐agent systems, an equivalent model is proposed. Considering that the signal input of multi‐agent systems is limited, this article will solve the input saturation problem. But in a real system, the actuator would probably fail. Therefore, a fault tolerant control algorithm is proposed to solve the fault problem in the systems. In this article, an adaptive distributed controller is designed to eliminate the uncertainty of the systems. At the same time, the integral barrier Lyapunov function is selected to verify the stability. Finally, a simulation example is given to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In advanced liver fibrosis (LF), macrophages maintain the inflammatory environment in the liver and accelerate LF deterioration by secreting proinflammatory cytokines. However, there is still no effective strategy to regulate macrophages because of the difficulty and complexity of macrophage inflammatory phenotypic modulation and the insufficient therapeutic efficacy caused by the extracellular matrix (ECM) barrier. Here, AC73 and siUSP1 dual drug‐loaded lipid nanoparticle is designed to carry milk fat globule epidermal growth factor 8 (MFG‐E8) (named MUA/Y) to effectively inhibit macrophage proinflammatory signals and degrade the ECM barrier. MFG‐E8 is released in response to the high reactive oxygen species (ROS) environment in LF, transforming macrophages from a proinflammatory (M1) to an anti‐inflammatory (M2) phenotype and inducing macrophages to phagocytose collagen. Collagen ablation increases AC73 and siUSP1 accumulation in hepatic stellate cells (HSCs) and inhibits HSCs overactivation. Interestingly, complete resolution of liver inflammation, significant collagen degradation, and HSCs deactivation are observed in methionine choline deficiency (MCD) and CCl4 models after tail vein injection of MUA/Y. Overall, this work reveals a macrophage‐focused regulatory treatment strategy to eliminate LF progression at the source, providing a new perspective for the clinical treatment of advanced LF. [ABSTRACT FROM AUTHOR]

Summary: In this paper, for the nonholonomic tractor‐trailer system with slipping and skidding, a full state‐triggering implementation of a tracking controller is proposed. Trailers are an important part, and their knowledge is crucial for the safety and control of the vehicle. Without considering system performance constraints, trailers may deviate from their expected position, leading to collisions. Therefore, there is still great interest in addressing the constraint control issues that arise in modern technologies related to network communication. Based on the backstepping method, bounded measurement errors are introduced into the continuous sampling controller considering intra‐vehicle communications. Then two neural networks are used to model unknown dynamics of the system with event sampling inputs, thereby decoupling the design of the control inputs. Finally, we prove the input‐to‐state‐like stability of a continuously sampled controller, and the given event execution control law can ensure the boundedness of measurement errors. Simulation results show the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

In this paper, we present a novel controller design method for stochastic nonlinear systems with unmodeled dynamics, uncertain parameters, and unknown covariance noise. In order to deal with these uncertainties, a new event‐based small gain controller is designed. The event‐triggered scheme can reduce the computational burden caused by disturbance and noise. By combining the technique of changing supply rate with small gain condition, a stochastic input‐to‐state practically stability Lyapunov function is obtained for the subsystem. Simultaneously, the changing supply function is used to treat with unmodeled dynamics. Based on backstepping process and adaptive control approach, the influence of unknown covariance noise is overcome. It is proved that the designed state‐feedback controller can ensure the overall system is stochastic input‐to‐state practically stability. [ABSTRACT FROM AUTHOR]

Summary: Deep‐frying oil intake is considered to destroy body health. In this review, a meta‐analysis was performed to assess the effects of deep‐frying oil intake on the risk of intestinal barrier dysfunction. Following Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines, a systematic literature search was conducted in PubMed, Embase and Cochrane Central updated till April 2022 (CRD42022326306). A total of nine studies were included. The pooled results revealed that deep‐frying oil intake significantly exaggerated crypt damage of colon [weighted mean difference (WMD) = 4.55; 95% CI: 2.87, 6.24, P < 0.05], increased proinflammatory cytokine expression in plasma and colon tissue, and enhanced intestinal permeability [lipopolysaccharides content (WMD: 10.11 μg mL−1, 95% CI: 7.44, 12.79 μg mL−1, P < 0.05)]. Moreover, deep‐frying oil intake could change the gut microbiota and decrease the content of microbiota‐derived short‐chain fatty acids. In conclusion, our findings provide insights into the effect of deep‐frying oil intake on the intestinal barrier dysfunction. [ABSTRACT FROM AUTHOR]

• Molecular fractionation of HDOM at Fe oxyhydroxides-water interface was investigated. • High Mw, O-rich, aromatic compounds were preferentially absorbed by Fe oxyhydroxides. • Toxicogenomics-based assay was used to evaluate the genotoxicity evolution of HDOM. • Oxidative, membrane, and DNA stresses were primary responses upon exposure to HDOM. • Interface fractionation reduced genotoxicity of HDOM in oxidative and DNA stresses. Adsorption fractionation of dissolved organic matter (DOM) induced by soil minerals is a common geochemical process, which has been widely documented on natural DOM. Hydrochar is a promising functional material in soil remediation but can continuously release abundant endogenic DOM with potential biotoxicity. However, adsorption fractionation at molecular level and its influence on toxicity evolution of hydrochar-derived DOM (HDOM) at genetic level at the soil-water interface remain poorly understood. Herein, we investigated the molecular fractionation of HDOM on three typical soil iron minerals (i.e., ferrihydrite, goethite, and hematite). Results from ultrahigh-resolution mass spectrum showed that HDOM molecules with high molecular weight and high contents of unsaturated oxidized or aromatic structures (e.g., unsaturated phenolic compounds, polyphenols, and organic acids) were preferentially absorbed by iron oxyhydroxides, while aliphatic molecules and poorly oxygenated compounds (e.g., hydrocarbon, phenols, and alcohols) were retained in aqueous phase. Furthermore, we quantitatively evaluated their genotoxicity variation using a toxicogenomics assay using green fluorescence protein-fused whole-cell array, and results showed that oxidative, protein, membrane, and DNA stresses were primary responses upon exposure to original HDOM. Interface fractionation induced by iron oxyhydroxides significantly reduced genotoxicity of HDOM, especially for oxidative, membrane and DNA stresses. Overall, the selective absorption of HDOM molecules by iron oxyhydroxides shifted its biotoxicity, which might change the ecological effects of hydrochar amendment, e.g., microbial community structure, environmental pollutant transformation, and even the ecological function of terrestrial and aquatic ecosystems. These findings would contribute to unraveling the environmental geochemistry process of HDOM in the natural soil-water interface and provide a new insight into the biotoxicity of hydrochar usage to terrestrial and aquatic environments. [Display omitted] [ABSTRACT FROM AUTHOR]

In the last decade, research has clarified the binding interactions between immunoglobulin E (IgE) and its high-affinity receptor, the FcεRI alpha chain (FcεRI). The formation of the IgE-FcεRI complex is crucial in the context of atopic allergies, linking allergen recognition to cellular activation and disease manifestation. Consequently, pharmacological strategies that disrupt these interactions are vital for managing atopic conditions. Historically, the complexity of the IgE-FcεRI binding process and challenges in producing functional recombinant derivatives has complicated data interpretation. However, advancements in structural biology, protein engineering, and immunological studies have enhanced our understanding of these protein-protein interactions (PPI), facilitating the development of more effective therapies. The introduction of anti-IgE therapies underscores the significance of the IgE-FcεRI PPI in allergic asthma. IgE, that is present locally and systemically, serves as a sensory mechanism in the adaptive immune response, particularly in mast cells (MCs) and basophils. When bound to FcεRI, IgE enables rapid memory responses to allergens, but dysregulation can lead to severe allergic asthma. Thus, the reactivity of IgE sensors can be finely modulated using various IgE-associated molecules. This review explores the mechanisms underlying IgE-dependent MC activation and its regulation by these molecules, including the latest therapeutic candidates under investigation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Compound 4 was identified as a potent KDM7A inhibitor by a hierarchical screening. • MKRN1 was discovered as a target gene of KDM7A for the first time. • Compound 4 is more effective against triple-negative breast cancer than 2,4-PC. • Exhibits inhibitory effects on both taxol-resistant and non-resistant TNBC cells. KDM7A, a histone demethylase implicated in cancer proliferation, metastasis, and drug resistance, represents a crucial therapeutic target. Utilizing " mcule.com " for virtual screening of 100,000 compounds from the ZINC database, we identified 12 compounds with high affinity for KDM7A, with compound 4 emerging as the leading candidate for effectively inhibiting KDM7A's demethylase activity. Analysis of the GTRD database, the Breast Cancer Gene Expression Miner website, and recent studies highlighted MKRN1 , a gene associated with cell proliferation and drug resistance, as a key intersecting factor. Compared to 2,4-pyridine dicarboxylic acid, compound 4 significantly reduced breast cancer stem cells and induced G1 phase cell cycle arrest. Mechanistically, compound 4 inhibited KDM7A's binding to H3K27me3, decreased MKRN1 transcription, and increased the levels of cell cycle regulators p16, p21, and p27, while reducing stem cell markers ALDH1A1, CD44, and CD133. These findings suggest that compound 4 could serve as a promising lead for selective KDM7A-targeting drugs. Additionally, this study is the first to demonstrate MKRN1 as a downstream gene of KDM7A, showing significant inhibitory effects in both taxol-resistant and drug-sensitive triple-negative breast cancer (TNBC) cells. This research offers new insights into the anticancer mechanisms of KDM7A inhibitors and underscores KDM7A's potential as a therapeutic target against TNBC. [ABSTRACT FROM AUTHOR]

In this study, we examined multiple endocrine-disrupting ultraviolet-absorbing compounds (UVACs) in marine invertebrates used in personal care products and packaging. Modified QuEChERS and liquid chromatography UniSpray ionization tandem mass spectrometry were used to identify 16 UVACs in marine invertebrates. Matrix-matched calibration curves revealed high linearity (r ≥ 0.9929), with limits of detection and quantification of 0.006–1.000 and 0.020–3.000 ng/g w.w., respectively. In oysters, intraday and interday analyses revealed acceptable accuracy (93%–120%) and precision (≤18%), except for benzophenone (BP) and ethylhexyl 4-(dimethylamino) benzoate. Analysis of 100 marine invertebrate samples revealed detection frequencies of 100%, 98%, 89%, 64%, and 100% for BP, 4-hydroxybenzophenone, 4-methylbenzophenone, 4-methylbenzylidene camphor, and benzophenone-3 (BP-3), respectively. BP and BP-3 were detected at concentrations of 4.40–27.39 and < 0.020–0.560 ng/g w.w., respectively, indicating their widespread presence. Overall, our proposed method successfully detected UVACs in marine invertebrates, raising concerns regarding their potential environmental and health effects. [Display omitted] • Separation efficiency was compared using LC columns with C 18 , biphenyl, and PFP bonding phases. • Cleanup efficiency in pretreating marine invertebrate samples was optimized using QuEChERS with multiple cleanup sorbents. • Concentrations of UVACs in crustaceans, shellfish, and cephalopods in Taiwan were determined. • Noncancer and cancer risks of exposure to target compounds from the daily ingestion of marine invertebrates were evaluated. [ABSTRACT FROM AUTHOR]

Summary: This article studies the fixed‐time time‐invariant formation control problem for a class of uncertain nonlinear heterogeneous multi‐agent systems (HMASs) with actuator faults and partial unknown control directions. Throughout the formation process, the possibility of actuator faults in systems and unknown control directions between individual agents are taken into account. Lipschitz conditions are introduced to identify the continuous uncertain nonlinear functions. To estimate the agents' local immeasurable states in HMASs, a distributed fixed‐time observer is proposed, which can ensure that the states of follower agents are observed in fixed time. In addition, a distributed formation fault‐tolerant control scheme will handle actuator faults. By designing a Nussbaum function, the problem of partial unknown control directions for HMASs can be solved in fixed time. Based on the fixed time stability theory, it is proved that the closed‐loop stability and the tracking performance can be guaranteed in fixed time, that is, the achieved time is independent of any initial states. In the end, a simulation example is given to testify the effectiveness of the proposed control method. [ABSTRACT FROM AUTHOR]

Protein arginine methyltransferase 7 (PRMT7), a type III methyltransferase responsible solely for arginine mono-methylation, plays a critical role in numerous physiological and pathological processes. Recent studies have highlighted its aberrant expression or mutation in various cancers, implicating it in tumorigenesis, cancer progression, and drug resistance. Consequently, PRMT7 has emerged as a promising target for cancer diagnosis and therapeutic intervention. In this review, we present an overview of the molecular structure of PRMT7, discuss its roles and mechanisms in different cancer types, and analyze the binding modes and structure-activity relationships of reported PRMT7 inhibitors. Furthermore, we identify the challenges encountered in functional exploration and drug development targeting PRMT7, propose potential solutions to these challenges, and outline future directions for the development of PRMT7 inhibitors to inform future drug discovery efforts. [Display omitted] • PRMT7 is a type III methyltransferase that specifically catalyzes arginine mono-methylation. • The review provides a comprehensive overview of PRMT7's molecular structure, enhancing understanding of its functional mechanisms. • Outlines future directions for the development of PRMT7 inhibitors, aiming to inform and guide future drug discovery efforts in cancer treatment. • Suggestions for overcoming the identified challenges in PRMT7 research and drug development, aiming to facilitate progress in this area. [ABSTRACT FROM AUTHOR]

In this paper, the output feedback-based bipartite consensus problem for MASs of unstable heat equations is investigated. The interactions of participating individuals are cooperative and competitive on an undirected graph. In order to achieve accurate estimation of system state, a distributed state observer is proposed. By introducing a reversible transformation, the observer system is transformed into a new system, and the controller based on the new system states is designed, which guarantees the well-posedness and stability of the considered control system and the observer system due to the invertibility of the presented transformation. Similarly, the bipartite consensus is analysed and proved. Finally, the validity of the proposed method is verified by simulation examples. [ABSTRACT FROM AUTHOR]

In this paper, an event-triggered tracking optimization control method is proposed for nonlinear uncertain systems with H ∞ discounted cost. First, the linearization method using the infinite series expansion theorem is given. And the tracking control design problem is solved by appropriate state augment. Secondly, the zero sum differential game strategy is introduced to address the control design problem of uncertain systems with event-triggered inputs. The actor-critic-disturbance networks framework is used to approximate the optimization of event- triggered controller strategy, optimization costs, and the disturbance strategy, respectively. Due to the consideration of discrete time and continuous time dynamics, we put the impulsive system method to use and choose appropriate Lyapunov functions to prove stability and boundedness, at the same time, there will be no infinite triggering situation. Finally, the effectiveness of the proposed scheme is demonstrated by an example of a practical tractor system with n trailers through simulation compared with another typical design method. [ABSTRACT FROM AUTHOR]

Summary: Deep‐frying oil featuring total polar compound (TPC) has been found to be unhealthy. However, little information is available regarding the impact of TPC on the lipid digestion behaviour. In this study, three typical edible oils (palm oil, PO; high oleic acid peanut oil, HOA; and high linoleic acid sunflower oil, HLA) were selected to investigate the effect of deep‐frying on the lipid digestion. Digestion behaviour was monitored by pH‐Stat method in vitro. Digestibility rate analysis showed that free fatty acids release rate of all TPC groups was the slowest among corresponding fresh oils and deep‐frying oils, indicating deep‐frying decreased lipid digestion rate. Lipid droplet analysis uncovered that deep‐frying could increase lipid particle size. Correlation analysis showed the polymers in TPC are negatively correlated with digestion rate and particle size, suggesting the digestion behaviour of deep‐frying oil is related to TPC constitution. In conclusion, this study highlights that deep‐frying weaken the lipid digestion capacity, and the multiplicity of TPC distribution which vary in terms of FAs type contribute to differences of digestion behaviour in deep‐frying oils. [ABSTRACT FROM AUTHOR]

Background: Tissue ischemia usually leads to necrosis and is a threatening condition associated with reconstructive surgery. Promoting the survival of ischemic tissue is critical for improving clinical outcomes. Although various solutions based on stem cells have been reported, there are still limitations to clinical translation. The aim of this study was to develop an effective method to promote the survival of ischemic tissue. Methods: Adipose-derived CD34 + and CD34- cells were obtained by magnetic bead sorting from the stromal vascular faction (SVF). Adipose-derived stem cells (ADSCs) were collected by subculture. The angiogenic capacities of CD34 + cells, CD34- cells and ADSCs were evaluated in vitro by comparing mRNA and protein expression. Random axial flaps in nude mice were used to evaluate the efficacy of these cells in protecting tissue from necrosis. The effect of these cells in preventing inflammation was also evaluated. Results: Our data suggest that CD34 + cells expressed higher levels of angiogenetic factors and lower levels of inflammatory factors than the other cell types. More vessel branches were formed when human umbilical vein endothelial cells (HUVECs) were treated with conditioned medium from CD34 + cells than conditioned medium from the other cell types. Compared to ADSCs, CD34 + cells showed significantly higher efficacy in promoting tissue survival. More CD31 + cells and higher levels of angiogenic factors were observed in tissues from the CD34 + group than in those from the other groups. Lower levels of the proinflammatory factors TNF-α and IL-1b and higher levels of anti-inflammatory factors were found in the CD34 + group than in the other groups. Conclusion: Adipose-derived CD34 + cells showed better efficacy in improving ischemic tissue survival than ADSCs by reducing tissue inflammation and promoting angiogenesis. CD34 + cells can be obtained easily and may be suitable for clinical applications. [ABSTRACT FROM AUTHOR]

In this article, the adaptive sliding mode (ASM) control scheme of half-car active suspension systems with prescribed performance is studied. Because of the affected by model uncertainty, time-varying parameter, pavement roughness excitation, etc., the study of suspension systems can be regarded as the multivariable nonlinear control problem. First of all, the prescribed performance function (PPF) is applied to constrain the displacement and pitch angle of the suspension systems to ensure the transient and steady-state suspension responses. Second, an integral terminal sliding mode control method with strong robustness is put forward, which can make the system converge rapidly in a finite-time when it is far from the equilibrium point, solve the singularity problem in the control process, and reduce the chattering phenomenon in the traditional sliding mode control. Then, the neural networks (NNs) approximation characteristics are used to deal with unknown items in the design of the controller, and the Lyapunov stability theory is employed to analyze the stability of the closed-loop system. In the end, the comparative simulation results demonstrate the feasibility and effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

A novel adaptive controller for the half-car active suspension systems (ASSs), which can improve the riding comfortability and handling stability of the driver, is proposed in this paper. By using nonlinear mapping, it is demonstrated that the nonlinear ASSs with partial performance constraints are transformed into the novel pure-feedback systems without constraints. By introducing a modified dynamic surface control (DSC) into the Lyapunov function, the adaptive neural network (NN) controller is discussed. The unknown continuous functions are estimated by the NNs, and the boundedness of all signals in the closed-loop systems is guaranteed by the Lyapunov stability theory. Meanwhile, the performance constraints are not violated. Finally, the simulations are performed to clarify and verify the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

In this paper, an adaptive neural network (NN) controller is proposed for a class of nonlinear active suspension systems (ASSs) with hydraulic actuator. To eliminate the problem of “explosion of complexity” inherently in the traditional backstepping design for the hydraulic actuator, a dynamic surface control technique is developed to stabilize the attitude of the vehicle by introducing a first-order filter. Meanwhile, the presented scheme improves the ride comfort even when the uncertain parameter exists. Due to the existence of uncertain terms, the NNs are used to approximate unknown functions in the ASSs. Finally, a simulation for a servo system with hydraulic actuator is shown to verify the effectiveness and reliability of the proposed approach. [ABSTRACT FROM AUTHOR]

A method for in situ preparation of fluorescent AuNPs@AuNCs core/shell nanoparticles by the template of BSA coated gold nanoparticles was developed. The as-prepared AuNPs@AuNCs core/shell nanoparticles possessed advantages such as uniform size, improved monodispersity and excellent fluorescence. The AuNPs@AuNCs core/shell nanoparticles in powder and suspension form were applied to the detection of latent fingermark due to the above properties. The developed latent fingermarks by AuNPs@AuNCs core/shell powder on various surfaces can exhibit excellent ridge details with good contrast between the fingermarks and the substrate. Moreover, under alternative light sources, the latent fingermarks developed with AuNPs@AuNCs core/shell powder work well. The development of latent fingermarks was reported by using AuNPs@AuNCs core/shell nanoparticles because of uniform size, improved monodispersity and excellent fluorescence. The AuNPs@AuNCs core/shell nanoparticles in powder and suspension form were applied to the detection of latent fingermarks due to the above properties. The developed latent fingermarks by AuNPs@AuNCs powder on various surfaces can exhibit excellent ridge details with good contrast between the fingermarks and the substrate. Under alternative light sources, the latent fingermarks by AuNPs@AuNCs powder work well. [ABSTRACT FROM AUTHOR]

In this article, we study the control problem of the vehicle active suspension systems (ASSs) subject to actuator failure. An adaptive control scheme is presented to stabilize the vertical displacement of the car-body. Meanwhile, the ride comfort, road holding, and suspension space limitation can be guaranteed. In order to overcome the uncertainty, the neural network is developed to approximate the continuous function with the unknown car-body mass. Furthermore, to improve the transient regulation performance of ASSs when the actuator failure occurs, we propose a novel control scheme with the prescribed performance function to characterize the tracking error convergence rate and maximum overshoot in ASSs. Then, the stability of the proposed control algorithm can be proven based on the Lyapunov theorem. Finally, the comparative simulation results of two actuator failure types (i.e., the float fault and the loss of effectiveness fault) are given to demonstrate the effectiveness of the proposed control schemes. [ABSTRACT FROM AUTHOR]

Microfluidic devices with integrated minisolenoids, microvalves, and channels have been fabricated for fast and low-volume immunoassay using superparamagnetic beads and well-known surface bioengineering protocols. A magnetic reaction area can be formed in the microchannel, featuring a high surface-to-volume ratio and low diffusion distances for the reagents to the bead surface. Such a method has the obvious advantage of easy implementation at low cost. Moreover, the minisolenoids can be switched on or off and the magnetic field intensity can be tuned on demand. Fluids can be manipulated by controlling the integrated air-pressure-actuated microvalves. Accordingly, magnetic bead–based immunoassay, as a typical example of biochemical detection and analysis, has been successfully performed on the integrated microfluidic device automatically in longitudinal mode. With a sample consumption of 0.5 μl and a total assay time of less than 15 min, goat immunoglobulin G was detected and the method exhibited a detection limit of 4.7 ng/ml. [ABSTRACT FROM AUTHOR]

• Cylindrical fins in compact solar receivers are optimized using adjoint method. • 3-D fins have characteristics of varied cross-section along the height direction. • Thermal-hydraulic performance of 3-D fins is improved by 13 % and 20 %. • The highest entropy generation rate of 3-D fins is reduced by 8.5 % and 16.5 %. The compact solar receiver is a promising option for S-CO 2 solar receivers, designed to operate safely and efficiently under high-temperature, high-pressure, and high solar flux conditions. Adding fins with outstanding thermal-hydraulic performance in the mini-channel contributes to maximizing heat transfer performance and minimizing flow resistance for compact solar receivers. However, most of the research on high-performance fins is limited to two-dimensional optimization, ignoring the effect of shape changes in the height direction of the fins. The present study employs a combination of the finite volume method and the adjoint method to optimize single-row cylindrical fin shapes in three-dimensional for compact solar receivers, and the strengthening mechanism of high efficiency and low resistance is further revealed in the view of entropy generation. The results indicate: (1) three-dimensional fins exhibit significant variation in cross-section along the height direction, and each fin is unique; (2) three-dimensional fins exhibit more excellent thermal-hydraulic performance than cylindrical fins, showing an increase of 13 % and 20 % in the performance evaluation criterion (PEC) in case 1 (q w = 160 kW·m−2, v in = 0.487 m·s−1) and in case 2 (q w = 584 kW·m−2, v in = 1.778 m·s−1), respectively; (3) the entropy generation due to heat transfer is reduced by 4.9% and 3.9%; as well as the entropy generation due to pressure drop is decreased by 8.5 % and 16.5 %, in case 1 and case 2, respectively; (4) robustness results show that three-dimensional fins can maintain higher thermal-hydraulic performance than the initial cylindrical fin even under wide working conditions. [ABSTRACT FROM AUTHOR]

In this paper, for the multi-agent system, the Nash equilibrium (NE) search problem for non-cooperative game with state constraints under false data injection (FDI) attack is studied. The FDI attack can directly destroy the connectivity between agents, resulting in the performance degradation or even failure for most NE search algorithms. We propose a new distributed NE search method to improve the performance of NE algorithms under FDI attacks. The NE algorithm is designed to find the solution of NE under network attack and make the system recover after the attack. However, most of the existing results only studied the NE algorithm of the non-attacking system, and the existing results rarely take into account whether the system state exceeds the safety limit, which can cause the system to crash. This paper solves the state constraints problem of the multi-agent game under the FDI attack. Finally, the reliability of the algorithm is verified by a numerical result. [ABSTRACT FROM AUTHOR]

In this paper, an adaptive neural network (NN) control scheme is proposed for a quarter-car model, which is the active suspension system (ASS) with the time-varying vertical displacement and speed constraints and unknown mass of car body. The NNs are used to approximate the unknown mass of car body. It is commonly known that the stability and security of the ASSs will be weakened when the constraints are violated. Thus, the control problem of the time-varying vertical displacement and speed constraints for the quarter-car ASSs is a very important task because of the demand of the handing safety. The time-varying barrier Lyapunov functions are used to guarantee the constraints of the vertical displacement not violated, and it can prove the stability of the closed-loop system. Finally, a simulation example for the ASSs is employed to show the feasibility and rationality of the proposed approach. [ABSTRACT FROM AUTHOR]

Circadian clock genes in peripheral tissues usually play an important role in regulating the circadian rhythms. Light is the most important environmental signal for synchronizing endogenous rhythms with the daily light‐dark cycle, and compound eyes are known as the principal circadian photoreceptor for photic entrainment in most moths. However, there is little evidence for circadian timing in compound eyes. In the current study, we isolated the timeless gene, designated Ha‐tim (GenBank accession number: KM233162), from the cotton bollworm Helicoverpa armigera. Ha‐tim and period (Ha‐per) showed low messenger RNA levels in the compound eyes compared to the other tested adult organs. Ha‐tim and Ha‐per transcript levels were dependent on an endogenous rhythm that fluctuated over a daily cycle in the compound eyes and heads. The cycles of Ha‐tim and Ha‐per transcript levels followed similar time courses, and identical expression patterns of the two genes were observed in the compound eyes and heads. Ha‐tim and Ha‐per were down‐regulated in the compound eyes after light exposure, copulation and starvation. These results indicated that Ha‐tim and Ha‐per transcript levels were regulated by endogenous and exogenous factors. Our study helped to improve our understanding of the circadian clock machinery in compound eyes and other peripheral tissues. [ABSTRACT FROM AUTHOR]

Thermoelectric generation (TEG)-based waste heat recovery technology is an example of a low-grade energy recovery application. This study proposes a waste heat recovery system that can store the recovered energy and run low-power automotive car lamps. Experimental analysis was conducted to examine the output characteristics of the TEG-based waste heat recovery system, focusing on how the structural components and operational parameters influenced these characteristics. The study also explored and optimized the working strategy of the system for driving light-emitting diode (LED) car lamps. Both the dynamic output characteristics of the system and the lighting attenuation rule of the lamps were evaluated. The results revealed that increasing the heating temperature would improve the recovered energy of the system. However, when a high-power LED chip was used for heat generation instead of an electrically controlled heating plate, a slightly larger amount of energy was collected at the expense of a slightly lower thermoelectric conversion rate. Furthermore, connecting a supercapacitor to the waste heat recovery system for energy storage increased the operational time of the lamps. The supercapacitor also served as a buffer for power and voltage fluctuations caused by variations in the heating temperature. These findings demonstrate that the waste heat recovery system not only meets the requirements of the LED car lamps but can also power other low-voltage and low-power devices. [ABSTRACT FROM AUTHOR]

In this paper, the vibration control design of the Euler–Bernoulli beam with time-varying constraints is studied when the mass, bending stiffness and tension of the system parameters are known or unknown. For satisfying the time-varying constraints, the controller is designed and the system stability is analysed based on the tangent barrier Lyapunov function (TAN-BLF). Among them, the uncertainty of system parameters is dealt with by the adaptive method. In both cases, the vibration of the Euler–Bernoulli beam can be well restrained without violating the constraint conditions, and all signals in the system are bounded. Finally, the effectiveness of the proposed method is illustrated by a simulation example. [ABSTRACT FROM AUTHOR]

Phototaxis in nocturnal moths is widely utilized to control pest populations in practical production. However, as an elusive behavior, phototactic behavior is still not well understood. Determination of whether the opsin gene plays a key role in phototaxis is an interesting topic. This study was conducted to analyze expression levels and biological importance of three opsin genes ( Se-uv , Se-bl , and Se-lw ) and phototactic behavior of Spodoptera exigua . The three opsin genes exhibited higher expression levels during daytime, excluding Se-bl in females, whose expression tended to increase at night. And cycling of opsin gene levels tended to be upregulated at night, although the magnitude of increase in females was lower than that in males exposed to constant darkness. The results of western blotting were consistent with those of qRT-PCR. Furthermore, opsin gene expression was not influenced by light exposure during the scotophase, excluding Se-uv in males, and tended to be downregulated by starvation in females and copulation in both female and male moths. To determine the relationship between opsin gene expression and phototactic behavior, Se-lw was knocked down by RNA interference. Moths with one opsin gene knocked down showed enhanced expression of the other two opsin genes, which may play important roles in compensation in vision. The Se-lw- knockdown moths exhibited reduced phototactic efficiency to green light, suggesting that Se-LW contributes to phototaxis, and increases phototactic efficiency to green light. Our finding provides a sound theoretical basis for further investigation of visual expression pattern and phototactic mechanisms in nocturnal moths. [ABSTRACT FROM AUTHOR]

Britannin (Bri), isolated from Inula aucheriana, is a sesquiterpene lactone (SL), a class of secondary metabolites. Previous studies have suggested the anti-cancer potential of Bri; however, the molecular mechanism remains elusive. The present study investigated the effects of Bri on liver cancer progression. Our findings indicated that Bri significantly suppressed the growth of liver cancer cell lines. Mechanistic researches revealed that Bri induced apoptosis through the extrinsic and intrinsic apoptotic pathways, as evidenced by the increase of Caspase-8, -9 and -3 cleavages. In addition, Bri-triggered autophagy in liver cancer cells, supported by the up-regulation of light chain 3 (LC3) II, p62, autophagy-related 5 (ATG5) and Beclin 1, as well as the occurrence of autophagic vacuoles. Importantly, Bri increased AMPK activation, while decreased the activity of its down-streaming signal, mTOR. Of note, suppression of AMP-activated protein kinase (AMPK) activation using its inhibitor, Compound C, could inhibit both apoptosis and autophagy induced by Bri. Furthermore, Bri was found to induce reactive oxygen species (ROS) generation in hepatic cancer cells. Notably, reducing ROS production by its scavenger, N-acetyl cysteine (NAC), could down-regulate p-AMPK levels, while up-regulate the phosphorylated mechanistic target of rapamycin (p-mTOR) expressions, accompanied with the restored cell viability, as well as the reduced apoptosis and autophagy in Bri-treated liver cancer cells. Finally, Bri inhibited the tumor growth in vivo without side effects. In conclusion, our study illustrated that Bri could induce apoptosis and autophagy by activating AMPK regulated by ROS in liver cancer cells, supplying molecular bases for developing Bri into an effective candidate against liver cancer. [ABSTRACT FROM AUTHOR]

[Display omitted] Histone demethylation is a kind of epigenetic modification mediated by a variety of enzymes and participates in regulating multiple physiological and pathological events. Lysine-specific demethylase 7A is a kind of α-ketoglutarate- and Fe(II)-dependent demethylase belonging to the PHF2/8 subfamily of the JmjC demethylases. KDM7A is mainly localized in the nucleus and contributes to transcriptional activation via removing mono- and di-methyl groups from the lysine residues 9 and 27 of Histone H3. Mounting studies support that KDM7A is not only necessary for normal embryonic, neural, and skeletal development, but also associated with cancer, inflammation, osteoporosis, and other diseases. Herein, the structure of KDM7A is described by comparing the similarities and differences of its amino acid sequences of KDM7A and other Histone demethylases; the functions of KDM7A in homeostasis and dyshomeostasis are summarized via documenting its content and related signaling; the currently known KDM7A-specific inhibitors and their structural relationship are listed based on their structure optimization and pharmacological activities; and the challenges and opportunities in exploring functions and developing targeted agents of KDM7A are also prospected via presenting encountered problems and potential solutions, which will provide an insight in functional exploration and drug discovery for KDM7A-related diseases. [ABSTRACT FROM AUTHOR]

The substantial amount of heat released by power electronic devices as they go toward increasing frequency and higher integration offers significant challenges for electronics cooling. Dual-stage ionic wind generators with a V-shaped 'needles-to-rings' design are presented. To achieve higher cooling efficiency, the ionic wind flow distribution was managed by improving the structure of the sub-unit. The calculation was performed using a two-dimensional model. By coupling an electric field, flow field, the development of ionic wind flow was simulated. Experiments were carried out in order to assess the EHD properties of the designed ionic wind generators, as well as the cooling impact on a high-power LED chip. The findings show that the convergent outlet structure has several defects, resulting in large momentum loss. The dual grounded rings in the sub-unit may spread the ionic wind more efficiently, providing charged particles with a stronger forward driving force and more possibilities to produce ionic wind. The ionic wind has a wide distribution range, a maximum wind velocity of 2.46 m/s, and provides improved cooling for the LED chip. • Double-stage ionic wind generators with V-shaped structures are developed. • The ionic wind flow distribution is optimized for better cooling efficiency. • The dual grounding rings in the sub-unit effectively disperse the ionic wind. [ABSTRACT FROM AUTHOR]

• Discarded face mask was a vital source of micro(nano)plastics and organic chemicals. • Face mask earloops released more pollutants than their filtering layers at same mass. • Toxicogenomics-based assay was used to evaluate the genotoxicity of emitted pollutants. • Membrane and DNA stress were primary responses upon exposure to emitted pollutants. Micro(nano)plastics widely detected in aquatic environments have caused serious threat to water quality security. However, as a potential important source of micro(nano)plastics in surface water during the COVID-19 pandemic, the ecological risks of face mask waste to aquatic environments remain poorly understood. Herein, we comprehensively characterized the micro(nano)plastics and organic compounds released from four daily used face masks in aqueous environments and further evaluated their potential impacts on aquatic ecosystem safety by quantitative genotoxicity assay. Results from spectroscopy and high-resolution mass spectrum showed that plastic microfibers/particles (∼11%-83%) and leachable organic compounds (∼15%-87%) were dominantly emitted pollutants, which were significantly higher than nanoplastics (< ∼5%) based on mass of carbon. Additionally, a toxicogenomics approach using green fluorescence protein-fused whole-cell array revealed that membrane stress was the primary response upon the exposure to micro(nano)plastics, whereas the emitted organic chemicals were mainly responsible for DNA damage involving most of the DNA repair pathways (e.g., base/nucleotide excision repair, mismatch repair, double-strand break repair), implying their severe threat to membrane structure and DNA replication of microorganisms. Therefore, the persistent release of discarded face masks derived pollutants might exacerbate water quality and even adversely affect aquatic microbial functions. These findings would contribute to unraveling the potential effects of face mask waste on aquatic ecosystem security and highlight the necessity for more developed management regulations in face mask disposal. [Display omitted] [ABSTRACT FROM AUTHOR]

Discarded face masks from the global COVID-19 pandemic have contributed significantly to plastic pollution in surface water, whereas their potential as a reservoir for aquatic pollutants is not well understood. Herein, we conducted a field experiment along a human-impacted urban river, investigating the variations of antibiotic resistance genes (ARGs), pathogens, and water-borne contaminants in commonly-used face masks. Results showed that high-biomass biofilms formed on face masks selectively enriched more ARGs than stone biofilm (0.08–0.22 vs 0.07–0.15 copies/16 S rRNA gene copies) from bulk water, which mainly due to unique microbial communities, enhanced horizontal gene transfer, and selective pressure of accumulated contaminants based on redundancy analysis and variation partitioning analysis. Several human opportunistic pathogens (e.g., Acinetobacter , Escherichia - Shigella , Bacillus , and Klebsiella), which are considered potential ARG carriers, were also greatly concentrated in face-mask biofilms, imposing a potential threat to aquatic ecological environment and human health. Moreover, wastewater treatment plant effluents, as an important source of pollutants to urban rivers, further aggravated the abundances of ARGs and opportunistic pathogens in face-mask biofilms. Our findings demonstrated that discarded face masks provide a hotspot for the proliferation and spread of ARGs and pathogens in urban water, highlighting the urgent requirement for implementing stricter regulations in face mask disposal. [Display omitted] • High-biomass biofilms were formed on discarded face masks in urban river. • Distinctive microbial community structure was detected in face-mask biofilm. • Face-mask biofilm simultaneously enriched ARGs and opportunistic pathogens. • Multiple drivers for enhanced antibiotic resistomes in face-mask biofilm were proposed. • WWTP effluents exacerbated the accumulation of pollutants in face-mask biofilm. [ABSTRACT FROM AUTHOR]

Background: Carrot which contains lots of nutrients has a large demand around the world. The soluble sugar content in fleshy root of carrot directly influences its taste and quality. Sucrose, as an important member of soluble sugar, is the main product of photosynthesis in higher plants and it plays pivotal roles in physiological processes including energy supply, signal transduction, transcriptional regulation, starch and cellulose synthesis, and stress tolerance. Sucrose synthase is a key enzyme involved in sucrose metabolism and is closely related to sucrose content. However, the molecular mechanism involved in sucrose metabolism in carrot has lagged behind. Results: Here, carrot roots of five developmental stages from four carrot cultivars were collected, and the contents of soluble sugar and sucrose in different stages and cultivars were surveyed. Three DcSus genes (DcSus1, DcSus2, and DcSus3), with lengths of 2427 bp, 2454 bp and 2628 bp, respectively, were identified and cloned in carrot. Phylogenetic analysis from the deduced amino acid sequences suggested that three DcSus were clustered into three distinct groups (SUSI, II and III). Results of enzymatic profiles demonstrated that the DcSus activities showed decrease trends during taproot development. Correlation analysis indicated that the DcSus activity showed negative correlation with soluble sugar content and strong negative correlation with sucrose concentration. Quantitative real-time PCR analysis showed that the expression profiles of the DcSus genes are significantly different in carrot tissues (root, leaf blade, and petiole), and the expression levels of the DcSus genes in the leaf blade were much higher than that in the root and petiole. The expression profiles of DcSus genes showed strong negative correlation with both sucrose content and soluble sugar content. Conclusions: During carrot root development, the soluble sugar content and sucrose content showed increasing trends, while DcSus activities had persisting declinations, which may be due to the decreasing expression levels of genes encoding sucrose synthase. Our data demonstrate that synthesis of sucrose in carrot tissue is closely related with DcSus genes. The results from our study would not only provide effective insights of sucrose metabolism in carrot, but also are beneficial for biologists to improve carrot quality. [ABSTRACT FROM AUTHOR]

An adaptive control scheme is developed in the paper for nonlinear stochastic systems with unknown parameters. All the states in the systems are required to be constrained in a bounded compact set, i.e., the full state constraints are considered in the systems. It is for the first time to control nonlinear stochastic systems with the full state constraints. In contrast to deterministic systems, the stochastic systems with the full state constraints are more difficult to be stabilized and the design procedures are more complicated. By constructing Barrier Lyapunov Functions (BLF) in symmetric and asymmetric forms, it can be ensured that all the states of the stochastic systems are not to transgress their constraint bounds. Thus, the proposed scheme not only solves the stability problem of stochastic systems, but also overcomes the effect of the full state constraints on the control performance. Finally, it is proved that all the signals in the closed-loop system are semi-global uniformly ultimately bounded (SGUUB) in probability, the system output is driven to follow the reference signals, and all the states are ensured to remain in the predefined compact sets. The validity of the proposed scheme is verified by a simulation example. [ABSTRACT FROM AUTHOR]

In this paper, based on an adaptive nonbackstepping design algorithm, we proposed a novel variable universe of discourse fuzzy control (VUDFC) approach for a class of single-input-single-output strict-feedback nonlinear systems with unknown dead-zone inputs. Firstly, we convert the form of system into a normal form on the basis of some new state variables and coordinate transformation; at the same time, state-feedback control is changed to output-feedback control. Secondly, we design observers to estimate the new unmeasurable states. Then, different from considering the traditional backstepping-based fuzzy control scheme, we introduce a direct VUDFC scheme, which is mainly based on changing of contraction-expansion factors to modify the universe of discourse online, and fuzzy rules can automatically reproduce to develop the control performance; thus, the size of initial rule base is greatly reduced. This new algorithm can alleviate tracking error, improve the accuracy of the system, and strengthen robustness. Lastly, according to Lyapunov theorem analysis, we prove that all the signals in the closed-loop system can be guaranteed to be stable, and the output can track the reference signal very well. Simulation results illustrated the effectiveness of the proposed VUDFC approach. [ABSTRACT FROM AUTHOR]

Influenza hemagglutinin is a surface glycoprotein related to virus invasion and host immune system response. Understanding site specific glycosylation of hemagglutinin will increase our knowledge about virus evolution and can improve the design and quality of vaccines. In our study, we used glycoproteomic analysis based on multienzyme digestion followed by LC tandem MS analysis to determine the glycosylation of Influenza hemagglutinin (H1/A/California/04/2009) using the following steps: PNGaseF treatment combined with trypsin or pepsin digestion was used to determine the glycosites and glycan occupancy. Three enzymes, trypsin, AspN, and pepsin, were used separately to generate suitable glycopeptides for online LC tandem MS analysis. The glycan structure of a given glycopeptide was determined by collision-induced dissociation MS/MS fragmentation, and the peptide backbone information was provided by collision-induced dissociation (CID)-MS3 fragmentation. With this approach, 100% sequence coverage of the hemagglutinin sample was obtained. Six glycosylation sites fitting the sequon N-X-S/T were successfully confirmed, and the glycan heterogeneity as well as the ratios of glycoforms were determined at each site. [ABSTRACT FROM AUTHOR]

Superhydrophobic coatings have broad applications owing to their excellent water-resisting and self-cleaning properties. In this study, we have successfully fabricated coated meshes with robust and superhydrophobic surface (i.e., water-repellent magnesium stearate powders on substrates made of phenol-formaldehyde resin). These coated meshes showed superhydrophobicity with water contact angles exceeding 150° and excellent self-cleaning property both in air and oil circumstances. Additionally, the superhydrophobic surfaces also exhibited prominent mechanical stability, thermal stability, corrosion resistance, and oil/water separation properties (>92%). Therefore, it is believed that the facile fabrication presented in this study may provide a novel methodology and these robust and superhydrophobic coated meshes have potential applications in oil/water separation. [ABSTRACT FROM AUTHOR]

An adaptive control-based neural network for a n -link robot is studied and the considered robot can be transformed as a class of multi-input–multioutput systems. The position of the robot or the output of the transformed systems is constrained in a time-varying compact set. It is commonly known that the constant constraint belongs to a special case of the time-varying constraint, and thus, it can be more general for handling practical problem as compared with the existing methods for robot. The neural approximation is used to estimate the unknown functions of systems and the time-varying barrier Lyapunov function is used to overcome the violation of constraints. It can prove the stability of the closed-loop systems by using Lyapunov analysis. The feasibility of the approach is demonstrated by performing a simulation example. [ABSTRACT FROM PUBLISHER]

In this paper, we address an adaptive control problem for a class of nonlinear strict-feedback systems with uncertain parameter. The full states of the systems are constrained in the bounded sets and the boundaries of sets are compelled in the asymmetric time-varying regions, i.e., the full state time-varying constraints are considered here. This is for the first time to control such a class of systems. To prevent that the constraints are overstepped, the time-varying asymmetric barrier Lyapunov functions (TABLFs) are employed in each step of the backsstepping design and we also establish a novel control TABLF scheme to ensure the asymptotic output tracking performance. The performances of the adaptive TABLF-based control are verified by a simulation example. [ABSTRACT FROM AUTHOR]

Oxidative stress aggravates renal fibrosis, a pathway involved in almost all forms of chronic kidney disease (CKD). However, the underlying mechanism involved in the pathogenesis of renal oxidative stress has not been completely elucidated. In this study, we explored the role and mechanism of hypochlorite-modified albumin (HOCl-alb) in mediating oxidative stress and fibrotic response in a remnant-kidney rat model. Five-sixths nephrectomy (5/6 NX) was performed on the rats and then the animals were randomly assigned to intravenous treatment with either vehicle alone, or HOCl-rat serum albumin (RSA) in the presence or absence of SS-31 (administered intraperitoneally). A sham-operation control group was set up concurrently. Compared with the control group, 5/6 NX animals displayed marked mitochondrial (mt) dysfunction, as evidenced by decrease of mitochondrial membrane potential (MMP), ATP production, mtDNA copy number alterations and manganese superoxide dismutase (MnSOD) activity, release of cytochrome C (Cyto C) from mitochondria to the cytoplasm, and increase of mitochondrial reactive oxygen species in renal tissues. They also displayed increased levels of HOCl-alb in both plasma and renal tissues. These changes were accompanied by accumulation of extracellular matrix, worsened proteinuria, deteriorated renal function, and a marked increase of macrophage infiltration along with up-regulation of monocyte chemoattractant protein (MCP)−1 and transforming growth factor (TGF)-β1 expression. HOCl-alb challenge further exacerbated the above biological effects in 5/6 NX animals, but these adverse effects were prevented by administration of SS-31, a mitochondrial targeted antioxidant peptide. These data suggest that accumulation of HOCl-alb may promote renal inflammation and fibrosis, probably related to mitochondrial oxidative stress and dysfunction and that the mitochondrial targeted peptide SS-31 might be a novel therapy for renal fibrosis and chronic renal failure (CRF). [ABSTRACT FROM AUTHOR]

In this paper, an adaptive controller design is studied for single-input–single-output (SISO) nonlinear systems with parameter uncertainties and the systems are enforced to subject to the full state constraints. A remarkable feature of the constrained systems is that the so-called control direction is unknown, or in other words, the signs of control gains are unknown. In the existing results, we discover that all the state constraint control results are required to determine a priori knowledge of control direction. It will be inevitable to bring about a different design procedure and a difficult task when no a priori knowledge of control direction is known. To stabilize this class of systems, two parameter adaptive controllers with Nussbaum gain technique are constructively framed to overcome the unknown control direction problem, and the novel symmetric and asymmetric Barrier Lyapunov Functions (BLFs) are adopted to guarantee that the states are not to violate their constraints. Then, the proposed BLF strategy can be to conquer the conservatism of the traditional BLF-based controls for the full state constraints. Finally, two theorems are provided to show that all the signals in the closed-loop system are bounded, the outputs are driven to follow the reference signals and all the states are ensured to remain in the predefined compact sets. The effectiveness of the proposed scheme is performed via a simulation example. [ABSTRACT FROM AUTHOR]

The adaptive event-triggered control problem is studied for the flexible beam system modeled by partial differential equations (PDEs) with uncertain system parameters and state constraint. In the design process of the controller, the event-triggered mechanism of relative threshold strategy is added to reduce the communication pressure. It further makes the communication process more flexible and improves the system working ability. The tangent barrier Lyapunov function (TAN-BLF) is selected to ensure that the system states satisfy their corresponding time-varying constraint bounds. The adaptive technique is chosen to solve the uncertain parameter problem. The system stability is verified on account of Lyapunov stability analysis method, and the boundedness of all system signals is proved. Furthermore, the Zeno behavior is successfully avoided. Finally, simulation results show the effectiveness and rationality of the proposed control strategy. [ABSTRACT FROM AUTHOR]

In this work, we demonstrated facile and low-cost fabrication of highly sensitive SERS substrates via replacement reaction by immersing Cu foils into a AgNO 3 solution. Different morphologies of Ag nanostructures were observed on the substrate surface by controlling the reaction time. The growth mechanism of Ag nanostructures on the Cu substrates was also analyzed based on the nanostructure evolution. The Ag-Cu substrates showed optimum SERS enhancement at certain reaction time, and the minimum detected concentration of Rhodamine 6G is as low as 10 −13 M. The easy and low-cost fabrication makes the Ag-Cu SERS substrates promising for rapid, sensitive detection of targeted analytes, such as biomolecules, pollutants, and explosives in the environment. [ABSTRACT FROM AUTHOR]