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In this study, blueberry anthocyanins extract (BAE) was used to investigate its protective effect on arsenic-induced rat hippocampal neurons damage. Arsenic exposure resulted in elevated levels of oxidative stress, decreased antioxidant capacity and increased apoptosis in rat hippocampal brain tissue and mitochondria. Immunohistochemical results showed that arsenic exposure also significantly decreased the expression of mitochondrial biosynthesis-related factors PGC-1α and TFAM. Treatment with BAE alleviated the decrease in antioxidant capacity, mitochondrial biogenesis related protein PGC-1α/NRF2/TFAM expression, and ATP production of arsenic induced hippocampal neurons in rats, and improved cognitive function in arsenic damaged rats. This study provides new insights into the detoxification effect of anthocyanins on the nervous system toxicity caused by metal exposure in the environment, indicating that anthocyanins may be a natural antioxidant against the nervous system toxicity caused by environmental metal exposure. [Display omitted] • This study provides new insights into antagonizing the neurotoxicity caused by arsenic exposure in the environment. • This study has improved the molecular mechanism by which anthocyanins exert beneficial effects. • Mitochondrial biosynthesis and oxidative stress play a crucial role in arsenic induced neurotoxicity. [ABSTRACT FROM AUTHOR]

Extracting hot‐carriers before they relax back to the band edge will reduce thermal dissipation above the bandgap, which is one of the primary sources of efficiency loss in perovskite solar cells (PSCs). It requires slow cooling of hot‐carriers together with the efficient extraction of hot‐carriers. Here, a novel interface engineering is demonstrated by embedding radical‐containing nanographene (r‐NG●) between perovskite and poly[bis(4‐phenyl)(2,4‐dimethoxyphenyl)‐amine] (PTOAA) to harvest this excess energy. This strategy accelerates the extraction rate of the hot‐hole (3 times that of control at 400 K) by augmenting the relaxation channel, which is related to the “quasi‐SOMO” energy state of r‐NG●. Nonadiabatic molecular dynamics calculation further revealed that radical character promotes the rotation of the cation in perovskite, which contributes to generating strong nonadiabatic couplings and multiple phonon modes. In addition, the band bending effect of buried perovskite and improved conductivity of PTOAA also facilitate exciton dissociation and hole collection efficiency (97.5%). Consequently, the resultant r‐NG● decorated PSCs delivered an impressive efficiency of 24.20%, along with better thermal and humidity stability. Moreover, it can maintain 93% of its initial efficiency after 300 hours of illumination. [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests that Matrix metalloproteinase-9 (MMP-9) and −2 (MMP-2) are involved in the neuropathological processes by contributing to breaking the extracellular matrix and the tight junctions that constitute the blood-brain barrier (BBB). However, the influences of arsenic (As) on these two MMPs were inconsistent. In the cross-sectional study of 500 adults, serum MMP-2 and MMP-9 positively correlated with urine arsenic. And the positive correlation between urine tAs and serum MMP-9/2 was found in people older than 59 years. In vivo studies, we found that arsenic exposure or senescence might decrease number of neurons and neuritic density and increase serum and cortical MMP-9/2 levels. Furthermore, arsenic exposure or senescence could disrupt the tight junction of BBB and elevate MMP-9 and MMP-2 expression in the cerebral microvascular endothelium. The MMP-9 and MMP-2 are of particular interest when researching the link between arsenic exposure and nerve damage. • Arsenic exposure significantly increased serum MMP2 and MMP9. • Age and arsenic metabolism ability might modify the relationship between arsenic and serum MMP-9 or MMP-2. • Arsenic exposure may disrupt the BBB by increasing endothelial MMP-9 and MMP-2 in mice. • Senescence and arsenic may combine damage to the BBB and increase the risk of brain injury in mice. [ABSTRACT FROM AUTHOR]

Highlights • The vehicle nonlinear characteristics are considered by using the T-S fuzzy approach. • A new sliding mode control strategy is proposed based on the T-S fuzzy approach. • The effective region is considered for the bounded sector zone of the AFS system. • A model parameter observer is designed to obtain the real-time cornering stiffness. Abstract Active front steering (AFS) has drawn considerable attention due to its superiority in improving the vehicle safety. This paper proposes a new Takagi-Sugeno (T-S) fuzzy based sliding mode control (SMC) strategy for the AFS system to improve the cornering stability of vehicles. Different from the conventional SMC strategy, the control law of the proposed control strategy is designed based on the T-S fuzzy approach which deals with the nonlinearity of the tire in a simplified but effective way. In the design of the control strategy, the bounded sector zone in the T-S fuzzy approach is determined based on the working region of the AFS system, and a model parameter observer is constructed to obtain the real-time cornering stiffness of the vehicle. To evaluate the cornering performance, simulations are conducted via open-loop and closed-loop tests. Simulation results show that the proposed T-S fuzzy based SMC strategy, which considers the nonlinearity of the tire and multi-objective control, is able to improve the cornering stability of the vehicle as compared with the conventional SMC strategy. [ABSTRACT FROM AUTHOR]

Highlights • Compensation system based regulating mechanism with grey neural network or fuzzy neural network for nonlinear hydraulic adjustable damper. • Particle swarm optimization optimized sliding mode control method for multi-objective control of semi-active suspension systems. • Online hardware-in-the-loop test on quarter car test rig for practical application of vehicle semi-active suspension systems. Abstract In recent, the development of the automotive semi-active suspension (SAS) system with the nonlinear hydraulic adjustable damper (HAD) has attracted widely attention due to its superiorities of low energy consumption, fast response, durable, reliable and simple structure. Many existing SAS researches focus on control algorithms for limited objectives and assume the control signal is the damping force, but very few of them discusses how to realize the calculated damping force. To solve this problem, the unknown regulating mechanism of the nonlinear HAD should be modeled and a complex multi-objective control of the SAS system should be designed. Aiming at modeling the regulating mechanism of the nonlinear HAD, this work constructs a novel compensation system by using fuzzy neural network or grey neural network algorithm in order to realize the desired damping force by regulating the stepper motor angle adaptively. Meanwhile, a new multi-objective control strategy, particle swarm optimization based sliding mode control method, is originally proposed to calculate the desired damping force to achieve exact damping force control of the SAS system. To realize the practical application of the SAS system with the nonlinear HAD, an online hardware-in-the-loop test is conducted on a quarter car test rig. Numerical and experimental results illustrate that the modeled regulating mechanism of the nonlinear HAD and the proposed multi-objective control of SAS system are effective to improve the vertical performance of the vehicle and feasible in practical applications. [ABSTRACT FROM AUTHOR]

The multilayer plate has a great potential for automotive and aerospace applications. However, the complexity in structure and calculation of the response impede the practical applications of multilayer plates. To solve this problem, this work proposes a new plate finite element and a simplified finite element (FE) model for multilayer plates. The proposed new plate finite element consists of the shear and extension strains in all layers. The multilayer structure with the proposed new plate finite element is regarded as a reference to calculate the reference value of the transverse response. The simplified FE model of multilayer plates is proposed based on the equivalent bending stiffness by curve fitting of the reference value of the transverse response. Numerical study shows that this approach can be used to set up the simplified FE model of multilayer plates. [ABSTRACT FROM AUTHOR]

The reaction mechanism and kinetics for the abstraction of hydrogen and addition of hydroxyl radical (OH) to 2′-deoxycytidine have been studied using density functional theory at MX06-2X/6-311+G(d,p) level in aqueous solution. The optimized geometries, energies, and thermodynamic properties of all stationary points along the hydrogen abstraction reaction and the addition reaction pathways are calculated. The single-point energy calculations of the main pathways at CCSD(T)/6-31+G(d,p)//MX06-2X/6-311+G(d,p) level are performed. The rate constants and the branching ratios of different channels are evaluated using the canonical variational transition (CVT) state theory with small-curvature tunneling (SCT) correction in aqueous solution to simulate the biological system. The branching ratios of hydrogen abstraction from the C1′ site and the C5′ site and OH radical addition to the C5 site and the C6 site are 57.27% and 12.26% and 23.85% and 5.69%, respectively. The overall calculated rate constant is 4.47 × 109 dm3 mol−1 s−1 at 298 K which is in good agreement with experiments. The study could help better understand reactive oxygen species causing DNA oxidative damage. [ABSTRACT FROM AUTHOR]

Various subgroups of CD8+ T lymphocytes do not only demonstrate cytotoxic effects, but also serve important regulatory roles in the body's immune response. In particular, CD8+ regulatory T cells (CD8+ Tregs), which possess important immunosuppressive functions, are able to effectively block the overreacting immune response and maintain the body's immune homeostasis. In recent years, studies have identified a small set of special CD8+ Tregs that can recognize major histocompatibility complex class Ib molecules, more specifically Qa‑1 in mice and HLA‑E in humans, and target the self‑reactive CD4+ T ce​lls. These findings have generated broad implications in the scientific community and attracted general interest to CD8+ Tregs. The present study reviews the recent research progress on CD8+ Tregs, including their origin, functional classification, molecular markers and underlying mechanisms of action. [ABSTRACT FROM AUTHOR]

This paper investigates the adaptive event-triggered dynamic output feedback control problem for vehicle active suspension systems with nonlinearity and uncertainty based on interval type-2 fuzzy method. Firstly, considering the dynamic behaviors of the spring and shock absorber are highly nonlinear, a fuzzy suspension model is established to capture the nonlinearity and uncertainty of the suspension systems based on interval type-2 Takagi-Sugeno fuzzy rules. Secondly, in order to decrease the transmission burden, an event-triggered mechanism is employed to decide whether the sampled signal is transmitted or not with an adaptive triggering threshold. Thirdly, by combining the fuzzy dynamic output feedback control law with event-triggered mechanism, a co-design method of fuzzy controller and event generator is proposed to improve the suspension performances and save network resources simultaneously. Finally, experimental tests under multiple pavement are implemented to verify that the proposed method can improve the performance of ride comfort and reduce communication burden simultaneously, despite the existence of unmeasurable states and nonlinearities. [ABSTRACT FROM AUTHOR]

Five screening criteria for RA 3 X 3 compounds (R = La, Sm, Gd, Tb, Dy, Ho, Er; A = Cd, Zn; X = As, P). [Display omitted] • The potential of RA 3 X 3 compounds as solar cells is measured via first principles calculations. • LaCd 3 P 3 is found to be a suitable photovoltaic material with a high absorption coefficient and a high efficiency limit. Results are obtained and compared at different levels of theory. Searching for photovoltaic materials with high efficiency conforms to the goal for accessing low carbon and sustainable energy. This work explores the properties of RA 3 X 3 compounds (R = La, Sm, Gd, Tb, Dy, Ho, Er; A = Cd, Zn; X = As, P) through a screening process, focusing on the huge potential of RCd 3 P 3 series for further investigation in photovoltaic applications. Results show that RCd 3 P 3 series with a direct or quasi-direct bandgap have an ultra-low exciton binding energy, which is favorable for separating electron and hole pairs. Moreover, these candidates possess high optical absorption in the visible light regions, and the power conversion efficiency limit of RCd 3 P 3 series can be as high as 24.5 % at the thickness of 4 μm. These results could enrich the database of potential solar cells based on lanthanide materials. [ABSTRACT FROM AUTHOR]

Abstract As an effective approach of suppressing vibrations, the constrained layer damping (CLD) has drawn wide attention from the automotive and aerospace industries. However, most of the existing investigations focus on the beam structures with CLD and few studies have been done on the plate structures with CLD. Considering the practical applications, this work studies the finite element (FE) modeling of plate structures with CLD by considering the shear and extension strains in all of three layers. To reduce the computational cost and ensure the accuracy, a simplified single-layer equivalent method is originally proposed to model the plate structure with CLD based on the equivalent material properties. In this method, the equivalent material properties are obtained by defining a new equation which includes the equivalent bending stiffness. By nonlinear regression of these responses at resonance frequencies, the equivalent bending stiffness can be obtained, and the plate structure with CLD can be regarded as a regular single-layer plate for modeling. The simulation result shows that the proposed simplified single-layer equivalent method using single-layer equivalent material properties is efficient and accurate for modeling plate structures with CLD. [ABSTRACT FROM AUTHOR]

Summary: This article is concerned with the problem of robust fuzzy fault tolerant control for the nonlinear active suspension system via adaptive hybrid triggered scheme. To describe the system with high nonlinearity, a Takagi‐Sugeno fuzzy approach is applied by weighting a series of linear subsystems. During the design of the controller, the actuator failure is taken into consideration. To ease the network communication pressure, a novel adaptive hybrid triggered scheme is proposed for the suspension system. By applying a Bessel‐Legendre inequality and a Jensen's inequality together, the control algorithm can be derived in the form of linear matrix inequalities with less conservatism. Finally, compared with the existing sampled‐data H∞$$ {H}_{\infty } $$ control and adaptive event triggered H∞$$ {H}_{\infty } $$ control, numerical simulations are performed to demonstrate the effectiveness and superiority of the proposed controller. [ABSTRACT FROM AUTHOR]

This paper proposes a novel integrated controller with three-layer hierarchical structure to coordinate the interactions among active suspension system (ASS), active front steering (AFS) and direct yaw moment control (DYC). First of all, a 14-degree-of-freedom nonlinear vehicle dynamic model is constructed. Then, an upper layer is designed to calculate the total corrected moment for ASS and intermediate layer based on linear moment distribution. By considering the working regions of the AFS and DYC, the intermediate layer is functionalised to determine the trigger signal for the lower layer with corresponding weights. The lower layer is utilised to separately trace the desired value of each local controller and achieve the local control objectives of each subsystem. Simulation results show that the proposed three-layer hierarchical structure is effective in handling the working region of the AFS and DYC, while the quasi-experimental result shows that the proposed integrated controller is able to improve the lateral and vertical dynamics of the vehicle effectively as compared with a conventional electronic stability controller. [ABSTRACT FROM PUBLISHER]

• A novel magnetorheological fluid damper inverse model is constructed based on the radial basis function neural network. • The filter performance function is employed in the semi-active suspension system as the reference state. • A unified frame is developed to study the semi-active suspension system with various disturbances. The magnetorheological fluid semi-active suspension system has been widely employed in vehicles. In general, the output force of the magnetorheological fluid damper varies with service time and temperature, which will cause the controller performance to degrade or even fail. To conquer this problem, this study proposes a compensatory backstepping strategy for the magnetorheological fluid suspension system. First, the normalized phenomenological model is introduced to simulate the nonlinear characteristics of the magnetorheological fluid damper. Second, the adaptive radial-basis function neural network is employed to construct the inverse model of the magnetorheological fluid damper. Next, the reference state is calculated by the filter performance function to trade off the vehicle handling stability and ride comfort. Finally, the voltage-force compensator is constructed to improve the robustness of the controller under input time delay, external noise disturbance, and actuator failures. Furthermore, the performances of the magnetorheological fluid damper, inverse magnetorheological fluid model, and compensatory backstepping controller are simulated under bump and random excitations. It is found that the proposed compensatory backstepping controller shows good improvement in the semi-active suspension system with time delay, noise disturbance, and actuator failure. [ABSTRACT FROM AUTHOR]

Skeletal fluorosis is a chronic metabolic bone disease caused by long-term excessive fluoride intake. Abnormal differentiation of osteoblasts plays an important role in disease progression. Research on the mechanism of fluoride-mediated bone differentiation is necessary for the prevention and treatment of skeletal fluorosis. In the present study, a rat model of fluorosis was established by exposing it to drinking water containing 50 mg/L F−. We found that fluoride promoted Runt-related transcription factor 2 (RUNX2) as well as superoxide dismutase 2 (SOD2) and sirtuin 3 (SIRT3) expression in osteoblasts of rat bone tissue. In vitro, we also found that 4 mg/L sodium fluoride promoted osteogenesis-related indicators as well as SOD2 and SIRT3 expression in MG-63 and Saos-2 cells. In addition, we unexpectedly discovered that fluoride suppressed the levels of reactive oxygen species (ROS) and mitochondrial reactive oxygen species (mtROS) in osteoblasts. When SOD2 or SIRT3 was inhibited in MG-63 cells, fluoride-decreased ROS and mtROS were alleviated, which in turn inhibited fluoride-promoted osteogenic differentiation. In conclusion, our results suggest that SIRT3/SOD2 mediates fluoride-promoted osteoblastic differentiation by down-regulating reactive oxygen species. [ABSTRACT FROM AUTHOR]

A composite steel plate shear wall system consists of a steel plate shear wall with reinforced concrete panels attached to one side or both sides by bolts or connectors. This arrangement restrains the possible occurrence of out-of-plane buckling of thin-walled steel plate, thus significantly increasing the load-carrying capacity and ductility of the overall wall. Experimental studies on composite steel plate shear walls and steel plate shear walls connected with frame beams were carried out. The experimental results illustrated the good ductility and excellent energy dissipation capacity of composite steel plate shear walls. The load-carrying capacity and energy dissipation capacity of steel plate shear walls clearly increased compared with those of steel plate shear walls. Meanwhile, a finite-element model was developed to analyse the behaviour of steel plate shear walls and composite steel plate shear walls, and its accuracy was validated by making comparisons with the experimental results. Based on the finite-element analysis results, a simplified model of steel plate shear walls was proposed, and it is suggested that this can be used in the analysis of shear wall systems in high-rise buildings. [ABSTRACT FROM AUTHOR]

The experimental results of composite steel plate shear walls and steel plate shear walls connected to frame beams only were presented. The influences of concrete panels and height-to-thickness ratio of steel plate were studied. Meanwhile, the finite element software ANSYS was applied to develop the model. The behavior of composite steel plate shear walls was analyzed. The experimental results show that both steel plate shear walls and composite shear walls have good ductility. In composite steel plate shear walls, the concrete panels resist its out-of-plane deformation and make the steel plate shear wall work in plane. Thus the hearing capacity and energy dissipation capacity increase evidently. When the concrete panel thickness is over a special value, the out-of-plane deformation of steel plate can be fully restrained. The bearing capacity of composite steel plate shear wall mainly relies on the span-to-height ratio of steel plate. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of hand-arm posture, grip force, push force, and vibration excitation intensity on the mechanical impedance of human hand-arm system, a test system with a self-developed vibration handle has been prepared. Based on the testing system, the mechanical impedance of the hand-arm system of seven Chinese adult males were tested and calculated under the random vibration excitation with the frequency of 10–1000 Hz. The results reveal that when the frequency is lower (<40 Hz), the hand-arm system with an elbow angle of 180o produces a higher mechanical impedance; when the frequency ranges from 40 Hz to 100 Hz, the hand-arm system with an elbow angle of 90o generates a higher mechanical impedance; while when the frequency is higher (>100 Hz), the hand-arm posture seems to have no obvious effect on the mechanical impedance. Higher grip or push force would increase the frequency corresponding to the peak value of the mechanical impedance and often correspond to a higher mechanical impedance in a specific frequency range (30–200 Hz). When the frequency is lower (<140 Hz), vibration intensity has certain effects on the mechanical impedance of the hand-arm system. In conclusion, vibration intensity does not directly affect the mechanical impedance, but an increase in grip or push force often causes an increase in mechanical impedance and a higher frequency that corresponds to the peak of mechanical impedance. [ABSTRACT FROM AUTHOR]

The semi-active suspension (SAS) system has been one of the most attractive topics due to its simplicity and effectiveness in the control of vehicle dynamics. This research proposes a cuckoo search optimized proportional-integral-derivative (CS-PID) strategy for the damping force control of the semi-acive suspension system in order to improve vehicle ride quality. Firstly, a quarter-car suspension model with air spring and variable hydraulic damper (VHD) is developed. By constructing the detailed analytical model and describing the working process, the regulating mechanism and external characteristics of the VHD are presented. Subsequently, the CS-PID strategy is designed to generate the desired damping force according to the vehicle states in real-time, followed with the evaluation of the proposed strategy. Finally, the experimental tests are carried out to verify the accuracy of the VHD model and examine the feasibility of the proposed strategy. The numerical simulation reveal that the proposed control strategy is effective in improving the vehicle performance and the experimental results show that the CS-PID strategy can be successfully implemented in the suspension system for practical use. [ABSTRACT FROM AUTHOR]

Summary: It is well known that the map‐based control can reduce the computational burden of the automotive on‐board controller. This paper proposes an output‐feedback model‐reference adaptive control algorithm to calibrate the map‐based anti‐jerk controller for electromechanical clutch engagement. The algorithm can be used to adaptively construct a data‐driven fuzzy rule base without resorting to manual tuning, so that it can overcome the problem of conventional knowledge‐based fuzzy logic design, which involves strenuous parameter‐tuning work in the construction of calibration maps. To accurately define the consequent of each fuzzy rule for anti‐jerk control, an output feedback law for computing the reference trajectory of clutch engagement is developed to eliminate the discontinuous slip‐stick transition, whereas an adaptive controller is designed to track the reference trajectory and compensate the nonlinearity. The convergence of the proposed output‐feedback model‐reference adaptive control algorithm is analyzed. Simulation results indicate that the proposed method can successfully reduce the excessive vehicle jerk and frictional energy dissipation during clutch engagement as compared with the conventional knowledge‐based fuzzy logic controller without fine tuning. [ABSTRACT FROM AUTHOR]

Semiactive suspension (SAS) system has been widely used for its outstanding performance in offering competent ride quality, road holding, and handling capacity. However, the road friendliness is also one of the crucial factors that should be attached in the design of the SAS system for heavy-duty vehicles. In this study, a fuzzy controlled hybrid-acceleration driven damper (ADD) and ground hook- (GH-) control strategy is proposed for SAS system of heavy-duty vehicles. Firstly, a quarter-vehicle model with SAS system is constructed. Then, aiming to improve the ride quality and road friendliness, a hybrid-ADD and GH-control strategy is proposed under the coordination of the fuzzy controller. Numerical results show that the ride quality and road friendliness of the SAS system with the proposed control strategy outperform those with traditional hybrid-sky hook and ground hook-control strategy. It is also verified that the proposed strategy is superior to the sole ADD approach and sole ground hook approach in improving the vehicle overall performance. [ABSTRACT FROM AUTHOR]