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This brief introduces a novel multifunctional quad-channel diplexer-integrated single-pole double-throw (SPDT) switch with three switchable operating modes. In Modes 1 and 2, the switch serves as a dual-band SPDT bandpass filter for distinct frequency bands and is compatible with time division duplexing (TDD) systems. In Mode 3, it serves as a quad-channel switchable diplexer suitable for both TDD and frequency division duplexing systems. The quad-channel diplexer-integrated SPDT switch is designed and implemented using microstrip technology, and its functionalities in the three modes are demonstrated. Experimental results revealed that, in comparison with state-of-the-art diplexers, the proposed multifunctional diplexer has greater advantages such as compact size, versatility, multimode switching, multichannel support, and high performance.

The Nb2C MXene film was prepared by tetrafluoroboric acid (HBF4) and hydrofluoric acid (HF) etching and vacuum extraction. The surface structure, properties, and composition of Nb2C MXene were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and other methods. The biocompatibility of Nb2C MXene film was evaluated by in vivo and in vitro experiments. The results show the layered, micro–nano surface structure of Nb2C MXene with abundant hydroxyl groups (—OH) on the surface. Compared with the control group, the proliferation rate of conjunctival fibroblasts cultured with 1 mg/mL Nb2C MXene is 72.15% (p<0.05). The cytotoxicity of Nb2C MXene is Grade 0 (p>0.05), and the hemolysis rate is 0.38% (<5%). The oxidative stress and inflammatory responses in rabbit ocular tissues are inhibited by Nb2C MXene film, which promotes wound healing without inducing fibrosis, and its micro–nano structure promotes cell adhesion and proliferation, demonstrating good biocompatibility.

Rigid instruments with limited flexibility utilized in the traditional endoscopic sinus surgery maybe damage the tissue when surgeon operates in the narrow space of nose specific area. Flexible continuum manipulator would solve this issue. However, current manipulators may not be able to address the intricate and varied surgical demands effectively, and they may not meet the surgical requirements adequately in terms of the flexibility, precision, and stiffness. This article introduced a novel modular continuum manipulator designed to offer exceptional adaptability, precision, and adjustable stiffness. The various sizes of the manipulators could be optimized according to different surgical scenario while taking its flexibility into account. Moreover, the model-based estimation and feedforward compensation control were applied to enhance its precision, taking into account the coupling effect of two sections and friction loss. Additionally, this study introduced a theoretical analysis on the feasibility of implementing variable stiffness for the manipulator, and the coupling was also lessened via increasing the stiffness of the first section. The experiments demonstrated that the maximum average deviation observed was 3.43 mm, which is equivalent to just 2.5% of the total length of the manipulator. Furthermore, the stiffness could be enhanced by up to 75%. Therefore, the proposed flexible manipulator has a potential for the nasal minimally invasive surgery.

To analyze the oxidative stress status and its association with tissue neutrophilia and oral steroid response in chronic rhinosinusitis with nasal polyps (CRSwNP) patients. The levels of total oxidant status (TOS) were detected in the sinonasal tissues by using specific assay kits. Tissue neutrophil was examined by immunohistochemical staining, and oxidant status index (OSI) was evaluated in polyps tissues, and the messenger RNA (mRNA) levels of superoxide dismutase 2 (SOD2), aldehyde dehydrogenase 1 (ALDH1A1), and microsomal glutathione S‐transferase 1 (MGST1) were examined using quantitative real‐time polymerase chain reaction in the sinonasal tissues. The receiver operating characteristics (ROCs) curve of ALDH1A1, MGST1, and SOD2 mRNA levels were evaluated to determine the steroid response of CRSwNP patients. The levels of TOS and OSI were significantly higher in CRSwNP and CRSsNP than in normal controls, and OSI in polyps tissues was positively associated with tissue neutrophilia and poor steroid response. The ALDH1A1, MGST1, and SOD2 mRNA levels showed comparable accuracy as predictors of poor steroid response indicated by the area under the curve. These findings provided evidence that the increased level of oxidative stress contributes to enhanced tissue neutrophilia and poor steroid response in CRSwNP patients. In brief, oxidative stress plays an important role in the pathogenesis of chronic rhinosinusitis. Hu et al. identified enhanced oxidative stress, especially in chronic rhinosinusitis with nasal polyps patients, which could be associated with tissue neutrophilia and poor steroid response. Antioxidative drug rottlerin and curcumin might be an add‐on therapeutic way. Total oxidant status and oxidant status index levels, aldehyde dehydrogenase 1,microsomal glutathione S‐transferase 1, and superoxide dismutase 2 messenger RNA levels are significantly increased in chronic rhinosinusitis with nasal polyps (CRSwNP) patients.Oxidase stress contributes to neutrophilic mucous inflammation and poor steroid response in Eastern CRSwNP patients.Rottlerin and curcumin might be used as an add‐on therapy on poor‐steroid‐response (or neutrophilic) CRSwNP patients. Total oxidant status and oxidant status index levels, aldehyde dehydrogenase 1,microsomal glutathione S‐transferase 1, and superoxide dismutase 2 messenger RNA levels are significantly increased in chronic rhinosinusitis with nasal polyps (CRSwNP) patients. Oxidase stress contributes to neutrophilic mucous inflammation and poor steroid response in Eastern CRSwNP patients. Rottlerin and curcumin might be used as an add‐on therapy on poor‐steroid‐response (or neutrophilic) CRSwNP patients.

Robotic exoskeleton assistance is an effective method for the treatment of patients with movement disorders. First, this article presents a variable stiffness knee exoskeleton robot, which can independently control stiffness and position and has a large stiffness range under low preload. Then, combined with the designed variable stiffness exoskeleton, a physical human–robot interaction (pHRI) control scheme based on joint torque estimation is proposed. Different from previous studies, this method uses the mechanical properties of the exoskeleton to achieve pHRI without complex control algorithms and force/torque sensors. Furthermore, the joint torque is estimated based on the surface electromyography signal and the Hill-based muscle model, and the exoskeleton can realize assist-as-needed function: when the subject trains with less effort, the exoskeleton maintains a high output physical impedance to provide high tracking accuracy; and when the subject trains with greater effort, the exoskeleton maintains a low output impedance to provide high physical compliance. Finally, we conducted experiments on three healthy subjects and two subjects with lower limb motor dysfunction to verify the effectiveness of the torque estimation method and the pHRI control scheme.

Continuum robot has great advantages in minimally invasive surgery (MIS) due to the slenderness and dexterity. But the friction and backlash result in the low trajectory tracking accuracy. This paper aims to study the transmission process of the driving force and the error compensation method. The statics is performed considering the frictional transmission process, and the variation of friction force with driving force is revealed by the model. The hysteresis effect of the tip trajectory is revealed. Then the relationship between the load history and the robot shape is studied, next, the deflection of the robot subject to the different loading forces can be predicted. The correctness of the mechanical model is verified by numerical simulation and experiments. Furthermore, the control methods according to the cable length and the driving force are compared respectively, and a method of error compensation according to the cable length is worked out considering the mechanical model. The rationality of the compensation method is validated by experiment. The results show that the compensation method based on cable length greatly improves the control accuracy, and the maximum deviation is 1.08 mm. The established model and compensation method create conditions for clinical application of the proposed continuum robot.

The shape information is the key to realize real-time, accurate, and effective control of continuum robots. Traditional image processing method and start-to-end-point fitting method are combined. Inertial measurement unit (IMU) and camera are used to capture the end position and attitude information of continuum robot and do not rely on the acquisition of the global image to solve the problem of limited vision in a traditional image processing method. In addition, a new start-to-end-point fitting method is proposed, which is the Pythagorean hodograph—Bézier (PH-B) fitting method. The new method simplifies the solving steps of control points of fitting curve. The control points can be obtained only through the geometric relationship and do not need to rely on an optimization algorithm for iterative solution. This method has good shape fitting accuracy and applicability in the curvature range from 0° to 90° through the simulation analysis. A variety of experiments are designed to verify the results. The experimental results show that the maximum shape reconstruction error by the proposed method is about 2 mm. This proves the applicability of the PH-B method in the shape reconstruction of continuum robots.

The poor spatial resolution of electrical impedance tomography (EIT) limits its use in medical devices because of its highly nonlinear and ill-posed nature. A novel hierarchical block sparse Bayesian learning (BSBL) method is designed for lung respiratory monitoring with EIT. It is its excellent modeling capability and noise robustness that allows BSBL to adaptively explore and exploit the internal conductivity distribution, e.g., block sparsity and intra-block correlation. First, the $K$ -nearest neighbor (KNN) strategy is employed to automatically group each block based on the clustering property and incorporated to constrain the intra-block correlation matrix based on the spatial distance. Second, a three-layer hierarchical BSBL model using weighted Laplace (WL) prior is considered to enhance the recovery performance. Finally, an efficient bound optimization (BO) method is performed for Bayesian inference, avoiding the tedious parameter adjustment. This leads to improvements in recovery performance, algorithm robustness, and computational efficiency. Moreover, root mean square error (RMSE), image correlation coefficient (ICC), and relative size coverage ratio (RCR) are applied for quantitative comparisons of image quality. Numerical simulations and in vivo lung respiratory experiments showed that the proposed KNN-BSBL-WL method outperforms existing referenced methods in terms of reconstruction accuracy and computational time. On average, KNN-BSBL-WL obtains the RMSE $= 0.07\,\,\pm \,\,0.02$ , ICC $= 0.96\,\,\pm \,\,0.01$ , and RCR $= 0.98\,\,\pm \,\,0.05$ , which are closest to the true values of the recorded snapshots obtained in the experiments. Meanwhile, the average time of KNN-BSBL-WL is 0.16 s, achieving an acceleration ratio close to $\sim 3$ compared with the referenced KNN-BSBL method. Therefore, the proposed method is an efficient and robust means of imaging reconstruction, which further improves the feasibility of EIT in respiratory clinical applications.

In this article, a multicircle planar electrical impedance tomography (EIT) sensor is proposed for three-dimensional (3-D) miniature imaging. There are two problems in 3-D miniature EIT imaging: 1) the spatial resolution is low since the number of electrodes is limited and 2) contact impedance influences image reconstruction quality severely. The proposed EIT sensor made by a printed circuit board (PCB) adopts a multicircle structure and tackles the two problems. Driven electrodes are distributed on the outermost two circles, while measurement electrodes are distributed on the innermost circle. Contact impedance is reduced since the area of driven electrodes could be larger than traditional ones by using the multicircle structure, and it is also owning to gold that is deposited on the surface of the electrodes. Moreover, a new driven-measurement pattern of the EIT sensor is proposed to improve the spatial resolution as well as image reconstruction quality. The proposed EIT sensor is verified by both simulation and experiment. The average image correlation coefficient (ICC) is as high as 0.8475 in simulation. Compared with the 16-electrode EIT sensor, ICC is improved by 39.16%. In the experiment, the average ICC of four standard objects is 0.8389. The proposed 3-D EIT sensor is good at miniature imaging.

A method for noninvasive real-time measurement of blood cardiopulmonary bypass is proposed by electrical capacitance tomography (ECT). An eight-electrode sensor ECT data acquisition system is designed, including sensor design and data acquisition module design. The system has a real-time imaging speed of 40 frames per second (FPS) and an average signal-to-noise ratio (SNR) of 64.59 dB per channel, which has been experimentally verified. First, the system is able to detect 6.25%–42.25% of the target area ratio (AR) when the sensor inner diameter is 20 mm, the outer diameter is 25 mm, and the image correlation coefficient (ICC) is not less than 0.7, which obtained by static experiments. Second, the corresponding voltage sum curve is different when different sizes of targets flow through the electrode coverage area. Dynamic experiments have verified that the sum of voltage curve for each frame image is available to further determine the size of the thrombus generated during the circulation process. Finally, dynamic experiments were performed using fresh porcine blood clots to mimic thrombus, which verified the feasibility of using ECT for in vitro thrombus detection.

Purpose: The supercritical design of tail rotor drive shaft has attracted more attention in helicopter design due to its high power–weight ratio and low maintenance cost. However, there exists excessive vibration when the shaft passes through the critical frequency. Dry friction damper is the equipment applied to the drive shaft to suppress the excessive vibration. In order to figure out the damping mechanism of the dry friction damper and improve the damping efficiency, the dynamic model of the shaft/damper system is established based on the Jeffcott rotor model. Design/methodology/approach: The typical frequency response of the system is studied through bifurcation diagrams, amplitude-frequency characteristic curves and waterfall frequency response spectrum. The typical transient responses under frequency sweeps are also obtained. Findings: The results show that the response of the system changes from periodic no-rub motion to quasi-periodic rub-impact motion, and then to synchronous full annular rub-impact, and finally, back to periodic no-rub motion. The slip of the rub-impact ring improves the stability of the system. Besides, the effects of the system parameters including critical dry friction force, rub-impact friction coefficient, initial clearance on the stability and the vibration damping capacity are studied. It is observed that the stability changes significantly varying the three parameters respectively. The vibration damping capacity is mainly affected by the critical dry friction force and the initial clearance. Originality/value: Presented results provide guidance for the design of the dry friction damper.

A new adaptive time delay estimation technique with sliding mode control method is proposed and investigated in this passage for cable-driven manipulators. Time delay estimation technique is an effective tool to compensate for unmodeled dynamics and unknown disturbance, and adaptive time delay estimation performs better due to its adaptive control gain. The proposed adaptive method is based on the fuzzy logic algorithm which has a great advantage in input–output mapping thank to its flexibility. Tuning procedure is addressed to reveal the implementation of the newly proposed algorithm. Moreover, the desired trajectory is taken as an input of adaptive algorithm and better control performance is obtained through this attempt. The proposed controller is ultimately uniformly bounded and proof using the Lyapunov method is provided. Finally, comparative experiments show the validity and effectiveness of the proposed controller.

The mechanical properties and microstructure of the A356-T6 wheel hub based on low pressure die casting-hot flow forming process were analyzed by means of optical microscopy (OM), scanning electron microscopy (SEM) and tensile tests. Results showed that the size of the eutectic region and the morphology of the Si phase were the main factors affecting the mechanical properties and fracture morphology of the wheel hub. There was a uniform distribution of eutectic area and fine Si phase morphology in the microstructure of the upper rim and lower rim, moreover, the ultimate tensile strength and yield strength of the upper rim reached 282.4MPa and 185.1MPa, respectively. The fractures were mainly composed of fine quasi-cleavage platform and dimple. The microstructure of the rim showed a long strip along the deformation direction and the eutectic structure and Si particles were uniformly distributed. Irregular polygonal eutectic regions and coarse rod-like Si particles were accumulating in the spoke, causing a serious decrease in mechanical properties, especially in the spoke center and spoke R angle.

In recent years, aerial manipulators consist of unmanned aerial vehicles and robotic manipulators have been widely utilized in aerial operations. The complex dynamic coupling effects between unmanned aerial vehicles and robotic manipulators will bring some issues to the motion control. Therefore, the article proposes a new control scheme for aerial manipulators. The proposed method includes three elements, that is, time-delay estimation, backstepping design, and nonsingular terminal sliding mode. The time-delay estimation technique is adopted to estimate the complex system dynamics and to bring a model-free feature of the system. With the backstepping design, the proposed control strategy can ensure the asymptotic stability of the closed-loop system by recursive procedure. To deal with the unmodelling dynamics and disturbances, and to assure finite-time convergence of the system states, the nonsingular terminal sliding mode is adopted. By combining three elements, the tracking performance of aerial manipulators is improved under unmodelling dynamics and disturbances. Global stability of closed-loop control system is analyzed using Lyapunov stability theory. Finally, comparative simulations are conducted, and the results show that the proposed controller has better performance than a conventional proportional–derivative controller or a nonsingular terminal sliding mode controller.

Ocular changes are traditionally associated with only a few hepatobiliary diseases. These changes are non-specific and have a low detection rate, limiting their potential use as clinically independent diagnostic features. Therefore, we aimed to engineer deep learning models to establish associations between ocular features and major hepatobiliary diseases and to advance automated screening and identification of hepatobiliary diseases from ocular images.

AbstractThe objective of this study was to investigate the effects of Allium mongolicumRegel (AM) and AM extracts on the growth performance, carcass parameters and meat quality of sheep. Forty sheep were randomly divided into four groups. The groups consisted of CON (basal diet), AM water extract (AWE; basal diet + 3.4 g/sheep/day AWE), AM ethanol extract (AEE; basal diet + 2.8 g/sheep/day AEE) and AM (basal diet + 10 g/sheep/day AM). The average daily gain (ADG) was improved (p < .05) and feed conversion ratio (FCR) was decreased (p < .05) in AWE, AEE and AM compared to CON. The loin eye area (LEA) and intramuscular fat (IMF) percentage were improved (p < .05) and cooking loss (CL) was decreased (p < .05) in AM, AWE and AEE compared to CON. The water holding capacity (WHC) was improved (p < .05) in AM and AWE compared to CON. The Warner–Bratzler shear force (WBSF) was decreased (p < .05) in AWE and AEE compared to CON. The levels of Σ polyunsaturated fatty acid (ΣPUFA) was increased (p < .05) and Σ saturated fatty acids (ΣSFA) was decreased (p < .05) in AM, AWE and AEE compared to CON. The levels of C18:1t-9, C18:1t-10 and C18:1t-11 were increased (p < .05) in AM and AEE compared to CON. The levels of C16:0 and n6/n3 ratio were decreased (p < .05) and levels of Δ9-desaturase C16 and elongase enzymatic activity were improved (p < .05) in AWE and AEE compared to CON. In conclusion, supplementation with AM and AM extracts could increase the growth performance, carcass quality traits and some healthier fatty acids.HighlightsAllium mongolicumRegel extracts increased average daily gain and decreased feed conversion ratio, improves carcass parameters in sheep.Allium mongolicumRegel extracts increased fat content in the Longissimus dorsimuscle.Allium mongolicumRegel extracts had beneficial effects on the fatty acid composition in the Longissimus dorsimuscle.

The joint coupling relationship was studied aiming at the motion coupling among multi cable-driven robot joints. A novel motion-decoupled mechanism is proposed and investigated. Two driving cables of distal joint traverse the modular in a specific routing. As a result, cables will wind and unwind at a certain angular along the groove in the following wheel. This design can effectively compensate the length change of cables during the rotating moving of proximal joint. Afterward, a 2–degree-of-freedom cable-driven manipulator platform using this motion-decoupled modular was set up. The verification experiment has shown a productive performance in realizing motion independence. Then, a new robust controller using time-delay estimation and fuzzy algorithm is proposed for the decoupled cable-driven manipulator. Thanks to time-delay estimation and fuzzy algorithm, the proposed controller is model-free, precise and easy to use under practical applications. Finally, contrast control experiments have been performed, and the result illustrates the superiority of the proposed control strategy.

To evaluate the damage capability of circumferential multiple explosive formed projectiles (MEFPs), it is required to predict the EFP forming velocity accurately and quickly. According to the circumferential MEFP liner characteristics of uniform circumferential distribution and layered axial structure, a simplified physical model of circumferential MEFPs is put forward innovatively. The Lagrange and Euler coupling algorithm is selected to simulate the simulation model, which is verified as equivalent to the circumferential MEFPs. Based on the energy conservation principle and the simplified equivalent physical model, the calculating model of the circumferential MEFP forming velocity is derived. The correctness and accuracy of the calculation model are verified by using the numerical simulation software and the test device of the round-shaped charge model.

Aiming at the requirements of lightweight, low energy consumption and low inertia of the manipulators for autonomous underwater vehicles, this article presents a novel underwater cable-driven manipulator for autonomous underwater vehicles. Thanks to the cable-driven mechanism, the motors are installed remotely from joints, which can reduce the disturbance of the motion of the manipulator to the system and extend the operation time under the premise of limited energy. Cable–sheath mechanism is used to realize the motors to be fixedly mounted on the base (postposition). A prototype named Polaris-II is assembled, and experiments are carried out with the time-delay control scheme. Although the control effect of a single time-delay controller is good, there exist large errors caused by the reversing of joints. Therefore, a fuzzy compensator is designed and added to the time-delay controller to suppress the large errors. The experimental results show that the time-delay controller with a fuzzy compensator has a good inhibitory effect on the large errors while maintaining good control effect.

Fate determination of neural stem cells (NSCs) is crucial for cortex development and is closely linked to neurodevelopmental disorders when gene expression networks are disrupted. The transcriptional corepressor chromodomain Y-like (CDYL) is widely expressed across diverse cell populations within the human embryonic cortex. However, its precise role in cortical development remains unclear. Here, we show that CDYL is critical for human cortical neurogenesis and that its deficiency leads to a substantial increase in gamma-aminobutyric acid (GABA)-ergic neurons in cortical organoids. Subsequently, neuronatin (NNAT) is identified as a significant target of CDYL, and its abnormal expression obviously influences the fate commitment of cortical NSCs. Cross-species comparisons of CDYL targets unravel a distinct developmental trajectory between human cortical organoids and the mouse cortex at an analogous stage. Collectively, our data provide insight into the evolutionary roles of CDYL in human cortex development, emphasizing its critical function in maintaining the fate of human cortical NSCs.

With the increasing demand for air operations, in this article, a control algorithm is proposed for a novel light cable-driven manipulator developed for aerial robots. On account of the control problem of cable-driven manipulators, we design a time delay estimation–based nonsingular terminal sliding mode controller with a fuzzy logic system to further improve the precision of joint position tracking. First, time delay estimation technique is adopted to estimate unknown dynamics of the manipulator system. And thanks to time delay estimation, accurate dynamic model is not needed and thus the controller is model-free which makes it more practical. The main part of the controller is nonsingular terminal sliding mode which ensures satisfactory tracking precision and good robustness under time delay estimation error and external disturbances. Besides, the boundary layer is introduced for reducing chattering and was regulated by a fuzzy logic system to realize a faster convergence. Global stability and finite time convergence to equilibrium of the closed-loop control system are analyzed using Lyapunov stability theory. Finally, comparative experiments are conducted through a newly designed planar cable-driven manipulator. Experimental results show that the proposed controller has a better performance compared with a conventional nonsingular terminal sliding mode controller while control effort is almost the same.

Currently, the acquisition of surface electromyographic (sEMG) signals commonly requires powerful and expensive equipment or systems. The signal analysis also requires additional equipment to process independently, which is time-consuming and the results are difficult to understand and directly apply to wearable robots. Therefore, this paper developed a sEMG signal device with a simple structure and high-performance cost ratio. The hardware architecture consists of a two-stage small-size amplifier with a total gain of 1000 and a band-pass filter from 10 to 150 HZ. Since real measured sEMG signals are usually corrupted by various types of noises, this paper designed an envelope processing to obtain the sEMG envelope signal which has stronger anti-interference ability than the raw signal, and it is also easier to apply to wearable robots. The proposed system is evaluated quantitatively by the experimental test and electrode groups analysis. In addition, the feasibility and effectiveness of the system is performed by measuring the sEMG signal of the forearm muscle group of four volunteers during motion action and extract the time domain feature to control a wearable robot. The sEMG envelope successfully manipulates the wearable robot with four different actions, whose precision is as high as a conventional sEMG device. The proposed system is promising in providing the reliable control interface of a wearable robot based on the sEMG.

In recent decades, urine drug testing in the workplace has become common in many countries in the world. There have been several studies concerning the use of the urine specimen validity test (SVT) for drug abuse testing administered in the workplace. However, very little data exists concerning the urine SVT on drug abuse tests from court specimens, including dilute, substituted, adulterated, and invalid tests. We investigated 21,696 submitted urine drug test samples for SVT from workplace and court settings in southern Taiwan over 5 years. All immunoassay screen-positive urine specimen drug tests were confirmed by gas chromatography/mass spectrometry. We found that the mean 5-year prevalence of tampering (dilute, substituted, or invalid tests) in urine specimens from the workplace and court settings were 1.09% and 3.81%, respectively. The mean 5-year percentage of dilute, substituted, and invalid urine specimens from the workplace were 89.2%, 6.8%, and 4.1%, respectively. The mean 5-year percentage of dilute, substituted, and invalid urine specimens from the court were 94.8%, 1.4%, and 3.8%, respectively. No adulterated cases were found among the workplace or court samples. The most common drug identified from the workplace specimens was amphetamine, followed by opiates. The most common drug identified from the court specimens was ketamine, followed by amphetamine. We suggest that all urine specimens taken for drug testing from both the workplace and court settings need to be tested for validity.

Dexmedetomidine (DEX) can protect the lung from ischemia‐reperfusion (I/R) injury, but the underlying mechanisms are not fully understood. The aims of this study were to determine whether DEX attenuates lung injury following lower extremity I/R and to investigate the related toll‐like receptor 4 (TLR4) signaling pathway. Twenty‐eight SD rats were divided into four groups (n = 7): Sham, I/R, I/R + DEX (25 μg/kg prior to ischemia), and I/R + DEX + Atip (250 μg/kg atipamezole before DEX treatment). Lower extremity I/R was induced by left femoral artery clamping for 3 hours and followed by 2 hours reperfusion. Quantitative alveolar damage and the wet/dry (W/D) ratio were calculated. Interleukin (IL)‐1, IL‐6, and tumor necrosis factor (TNF)‐α in the bronchoalveolar lavage fluid (BALF) and serum and myeloperoxidase (MPO) in the lung were measured. The TLR4 and MyD88 mRNA expression levels were measured by RT‐PCR, nuclear factor (NF)‐κB, and phosphorylated NF‐κB by western blot, respectively. Quantitative alveolar damage, W/D ratio, MPO, BALF and serum IL‐1, IL‐6, and TNF‐α, and TLR4, MyD88, NF‐κB, and p‐NF‐κB expression significantly increased in the I/R group relative to the Sham group. DEX preconditioning significantly reduced lung edema, and histological injury relative to the I/R group. Serum and BALF IL‐1, IL‐6, and TNF‐α levels, MPO activity and TLR4, MyD88, NF‐κB, and p‐NF‐κB expression were also significantly reduced in the I/R + DEX group compared with the I/R group. Atipamezole partially reversed all the aforementioned effects. DEX preconditioning protects the lungs against lower extremity I/R injury via α2‐adrenoceptor‐dependent and α2‐adrenoceptor‐independent mechanisms. It also suppresses the TLR4 pathway and reduces inflammation.

For the repetitive motion control, inaccurate model, and other issues of industrial robots, this article presents a novel control method that the proportion differentiation-type iterative learning parameters are self-tuning based on artificial bee colony algorithm. Considering the influence of the numerical value of iterative learning parameters on the control system, especially in the early iteration, the control effect is not satisfactory. Thus, the artificial bee colony algorithm is introduced in this article. Using bee colony as search unit, the parameters in iterative learning are optimized through the exchange of information and the survival of fittest between them. And then the optimized results are returned to iterative learning control algorithm. Finally, the digital simulation of a two-degrees-of-freedom manipulator and the experimental verification of a cable-driven robot with its first two joints are carried out. The results show that the iterative learning control based on the artificial bee colony algorithm has faster convergence and better control effect than the iterative learning control with fixed parameters.

The novel contribution of this article is to propose a neural network–based sliding-mode control strategy for improving the position-control performance of a tendon sheath–actuated compliant rescue manipulator. Structural design of a rescue robot with slender and compliant mechanical structure is introduced. The developed robot is capable of drilling into the narrow space under debris and accommodating complicated configuration in ruins. Dynamics modeling and parameters identification of a compliant gripper with flexible tendon sheath transmission are researched and discussed. Moreover, the neural network–based sliding-mode control scheme developed based on radial basis function network is proposed to improve the position-control accuracy of the gripper with modeling uncertainties and external disturbances. The stability of the proposed control system is demonstrated using Lyapunov stability theory. Further experimental investigation including trajectory-tracking experiments and step-response experiments are conducted to confirm the effectiveness of the proposed neural network–based sliding-mode control scheme. Experimental results show that the proposed neural network–based sliding-mode control scheme is superior to cascaded proportional–integral–derivative controller and conventional sliding-mode controller in position-control application.

A miniature resonant tactile sensor for tissue stiffness detection in robot-assisted minimally invasive surgery is proposed in this article. The proposed tactile sensor can detect tissue stiffness based on the principle of the resonant frequency shift when it contacts with tissue of different stiffness. A PZT (lead zirconate titanate) bimorph works simultaneously as the actuator and the sensing element, which is helpful for simplifying the structure. The resonant frequency shift can be deduced by measuring the electrical impedance of the PZT bimorph, since there will be an abrupt change of the impedance when resonance occurs. A unique structure of an Archimedean spiral metal sheet is introduced to restrict the outer size of the sensor within 10 mm and to keep the resonant frequency low. A theoretical model is established. Finite element method analyses are carried out to validate the working principle and it meets the theoretical model quite well. Several silicone samples are tested with the sensor and the results show that the proposed sensor is capable of measuring tissue stiffness within the range of 0–2 MPa, detecting and locating lumps inside tissue.

Artificial muscle is a kind of transmission actuator widely used in rehabilitation robots and wearable devices. However, there are some restrictions on the usage of these artificial muscles, including the short stroke length, complex structure, special power sources, and high nonlinear characteristics. Inspired by Hill-type muscle model, in this article, a new kind of artificial muscle using tendon–sheath and compliant springs is proposed to perform muscle-like characteristics. Force and deformation transmission models are proposed and validated by simulations and experiments. The experimental and simulation output results show nice goodness-of-fit and the R-square values are 0.9876 and 0.9046, respectively. Moreover, experiments are carried out in groups to analyze the transmission characteristics using different parameters, including variations of series springs, velocities, tendon diameters, and bending angles. The best R-square value of force–elongation curve and fitness curve could reach 0.9845, which indicates that the transmission model of the compliant artificial muscle can be used to express the transmission characteristics of the skeleton muscles.

Chronic inflammation induced by proinflammatory cytokines and chemokines is postulated to be involved in insulin resistance and β-cell dysfunction in type 2 diabetes mellitus (T2DM). Acarbose, the α-glucosidase inhibitor, is an oral antidiabetic drug for T2DM. Acarbose suppresses inflammatory cytokine production in patients with T2DM, though the underlying mechanisms are unclear. In the present study, we aimed to investigate the anti-inflammatory effects and the exact mechanisms of acarbose in human monocytic THP-1 cells. THP-1 cells were pretreated with acarbose and then stimulated with lipopolysaccharide (LPS). The levels of Th1-related chemokines, including interferon-γ-inducible protein-10 (IP-10), monocyte chemoattractant protein-1 (MCP-1), Th2-related chemokine macrophage-derived chemokine (MDC), and proinflammatory cytokine tumor necrosis factor-α (TNF-α), were determined by enzyme-linked immunosorbent assay. Intracellular signaling pathways were explored by Western blot analysis and using a chromatin immunoprecipitation assay. Acarbose suppressed the levels of IP-10, MCP-1, MDC, and TNF-α and downregulated phosphorylation of p38, c-Jun N-terminal kinase (JNK), extracellular signal–regulated kinase (ERK), and nuclear factor-kappa B-p65 (NF-κB-p65) in LPS-stimulated THP-1 cells. Acarbose suppressed LPS-induced acetylation of histones H3 (H3) and H4 in the IP-10and MCP-1promoter regions. These findings revealed the suppressive effects of acarbose on IP-10, MCP-1, MDC, and TNF-α production in THP-1 cells via, at least partially, the p38, JNK, ERK, and NF-κB-p65 pathways, as well as through epigenetic regulation via histone H3 and H4 acetylation. Our study points to the therapeutic anti-inflammatory potential of acarbose.

In this paper, we establish a generalized extreme Value-Pareto distribution model and derive an analytical expression of Weibull–Pareto distribution model. Based on a data sample of 26-year wave height, we adopt the new model to estimate the design wave height for 500, 700 and 1000-year return periods. Results show that the design wave height from Weibull–Pareto distribution is between that of the Weibull distribution and that of the Pearson-III distribution. For the 500-year return period design wave height, the results from the new model is 1.601% lower than those from the Weibull distribution and 1.319% higher than those from the Pearson-III distribution. The Weibull–Pareto distribution innovatively considers the fractal features, extreme-value statistics and the truncated data in the derivation process. Therefore, it is a more holistic and practical model for estimating the design parameters in marine and coastal environments.

The unintentional ingestion of toxic compounds in herbs is not uncommon in many parts of the world. To provide timely and life-saving care in the emergency department, it is essential to develop a point-of-care analytical method that can rapidly identify these toxins in herbs. Since electrospray laser desorption ionization mass spectrometry (ELDI/MS) has been successfully used to characterize non-volatile chemical compounds without sample preparation, it was used to identify toxic herbal compounds in this study. The herbal toxins were collected either by sweeping a metallic probe across the surface of a freshly cut herb section or by directly sampling extracts of ground herbal powder. The analytes on the probe were then desorbed, ionized and detected using ELDI/MS, wherein analysis of the herbal toxins was completed within 30 s. This approach allows for the rapid morphological recognition of herbs and early point-of-care identification of herbal toxins for emergency management and is promising in providing important toxicological information to ensure appropriate medical treatment.

Vitamin D has been considered to regulate calcium and phosphorus homeostasis and to preserve skeletal integrity. Serum 25-hydroxyvitamin D (25(OH)D) is the best indicator of vitamin D levels. The association of serum 25(OH)D deficiency with increased risk of type 1 diabetes (T1DM) and type 2 diabetes (T2DM) is controversial. We investigated serum 25(OH)D2and 25(OH)D3levels in diabetes patients by using liquid chromatography tandem mass spectrometry (LC-MS/MS). Serum 25(OH)D2 and 25(OH)D3 levels were measured with liquid chromatography tandem mass spectrometry in electrospray ionization positive mode. Chromatograms were separated using an ACE5 C18 column on a gradient of methanol. The total 25(OH)D levels were calculated as the sum of 25(OH)D3 and 25(OH)D2 levels. A total of 56 patients with T1DM and 41 patients with T2DM were enrolled in this study. There were 42 and 28 non-diabetic, age-matched volunteers who participated as the T1DM controls and the T2DM controls, respectively. The total 25(OH)D levels were lowest in the 21–40 age group. The levels of both 25(OH)D3 and the total 25(OH)D were significantly higher in the T1DM and T2DM groups than in the controls (p < 0.01 in T1DM and p < 0.05 in T2DM group, respectively). The 25(OH)D2 levels were only significantly higher in T1DM patients than in the controls. The percentages of vitamin D deficiency (total 25(OH)D less than 20 ng/mL) in the T1DM, T2DM, the T1DM controls and the T2DM controls were 7.1%, 0%, 14.3% and 3.6%, respectively. The percentages of vitamin D insufficiency (total 25(OH)D less than 30 ng/mL) in the T1DM, T2DM, the T1DM controls and the T2DM controls were 26.8%, 7.3%, 54.8% and 17.9%, respectively. The percentages of vitamin D deficiency and insufficiency were significantly lower in the T1DM patients than in the T1DM controls (p < 0.01). In the present study, both type 1 and type 2 diabetes patients had higher serum 25(OH)D levels and lower percentages of vitamin D deficiency/insufficiency.

Foods and drinks have been adulterated with illicit drugs to facilitate criminal activities. Unfortunately, conventional analytical methods are incapable of rapidly characterizing these drugs in samples, as serious interferences from sample matrices must be removed through tedious and time-consuming pretreatment. Ambient ionization mass spectrometry (AMS) generally does not require sample pretreatment and is thus a suitable tool for directly and rapidly detecting illicit drugs in samples in different physical states. In this study, thermal desorption electrospray ionization mass spectrometry (TD-ESI/MS), an AMS technique, was utilized to efficiently characterize illicit drugs spiked in samples including drinks, powders, and jelly candies. To perform sensitive analysis, the mass analyzer was operated in multiple reaction monitoring mode to monitor the molecular and fragment ions of the target analytes. The time required to complete a typical TD-ESI/MS analysis was less than 30 s. The limits of detection (LODs) for illicit drugs were found to be 100 ppb in drinks, 100–1000 ppb in instant powders, and 1.3–6.5 ng/mm2on stamp surfaces. FM2 and nitrazepam laced in the inner layer of a jelly candy were detected by TD-ESI/MS, showcasing the advantage of the technique for direct and rapid analysis as opposed to conventional methods.