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In the macro–micro composite motion process, the macro stage achieves rapid motion in a large workspace, while the micro stage realizes precise positioning within a small displacement. The large-stroke and high-speed motion of the macro stage is influenced by nonlinear friction, overshooting, and vibrations, making it challenging to achieve rapid stabilization within the travel range of the micro stage, thereby impacting equipment operation efficiency. This paper proposes a composite controller structure designed to solve the fast point-to-point positioning of the macro stage driven by a linear motor and enhance the trajectory tracking performance of the stage. The proposed composite control algorithm (CCA) includes velocity feed-forward, gain-scheduled proportional integral differential (PID) control, and a plug-in repetitive control method. By employing a tracking differentiator, velocity feed-forward, and a gain-scheduled PID controller, the control algorithm can realize rapid stabilization and positioning for the macro stage. Through velocity feed-forward, gain-scheduled PID control, and a plug-in repetitive controller, the control algorithm can reduce the trajectory tracking error of the stage. Simulations and experimental studies of point response and sinusoidal trajectory tracking are carried out on a macro–micro stage to verify the effectiveness of the composite controller for the linear motor. The experimental results demonstrate that the proposed composite controller effectively reduces the macro stage’s settling time and overshoot, and improves the accuracy of sinusoidal trajectory tracking, which lays a foundation for submicron positioning accuracy in high-speed macro–micro motion stages.

Abstract Small extracellular vesicles (sEVs) have been identified as a noteworthy paracrine mechanism of intercellular communication in diagnosing and managing neurological disorders. Current research suggests that sEVs play a pivotal role in the pathological progression of pain, emphasizing their critical function in the pathological progression of pain in acute and chronic pain models. By facilitating the transfer of diverse molecules, such as proteins, nucleic acids, and metabolites, sEVs can modulate pain signaling transmission in both the central and peripheral nervous systems. Furthermore, the unique molecules conveyed by sEVs in pain disorders indicate their potential as diagnostic biomarkers. The application of sEVs derived from mesenchymal stem cells (MSCs) in regenerative pain medicine has emerged as a promising strategy for pain management. Moreover, modified sEVs have garnered considerable attention in the investigation of pathological processes and therapeutic interventions. This review presents a comprehensive overview of the current knowledge regarding the involvement of sEVs in pain pathogenesis and treatment. Nevertheless, additional research is imperative to facilitate their clinical implementation. Graphical Abstract Schematic diagram of sEVs in the biogenesis, signal transmission, diagnosis, and treatment of pain disorders. Small extracellular vesicles (sEVs) are secreted by multiple cells, loading with various biomolecules, such as miRNAs, transmembrane proteins, and amino acids. They selectively target other cells and regulating pain signal transmission. The composition of sEVs can serve as valuable biomarkers for pain diagnosis. In particular, mesenchymal stem cell-derived sEVs have shown promise as regenerative medicine for managing multiple pain disorders. Furthermore, by modifying the structure or contents of sEVs, they could potentially be used as a potent analgesic method.

The three-axis parallel motion platform (TAPMP) with a common stator has low motion inertia, enabling highly precise and high-speed motion over a large range of strokes. The primary challenge faced by the TAPMP lies in the mutual pulling exerted between the common stator motors during motion. The driving forces generated by the motors are closely associated with their synchronization motion, a connection often overlooked in the design of existing controllers. To address this issue, this paper presents a novel synchronization controller with dynamics compensation (SC–DC) to achieve motion synchronization between the three motors, ultimately enhancing the platform’s tracking accuracy in task space. In this SC–DC method, the synchronization error of the common stator motors is introduced to represent the synchronized motion relationship between adjacent motors, and a dynamic feedforward control is adopted to compensate for the motor’s driving force. The stability of the proposed controller is analyzed using Lyapunov theory, demonstrating the convergence of both the tracking error and synchronization error. Trajectory tracking simulations and experimental studies are conducted on the TAPMP. The results show that, compared to the augmented proportional-derivative controller with dynamic compensation, the proposed controller significantly reduces both the MAE of the tracking error and synchronization error on the q1 motor by 71.88% and 73.02%, respectively, demonstrating its performance advantages in trajectory tracking and synchronization.

To improve the accuracy of the discrete element research, physical and simulation experiments were used to calibrate the cotton stalk contact parameters. Based on the stalk-stalk and stalk-steel contact mechanics, the parameters were measured in physical experiments, and the discrete element simulation software was used to build the stalk model. In the simulation process, the Plackett-Burman experiment was used to screen three significant factors from six initial factors. The steepest Plackett-Burman experiment was used to determine the optimal interval of the significant factors. A second-order regression model of the significant factors and the angle of repose was established according to the Central Composite design experiment. The best parameter combination of the significant factors was then obtained: the coefficient of static friction on stalk-steel contact was 0.31, the coefficient of static friction on stalk-stalk contact was 0.62, and the coefficient of rolling friction on stalk-stalk contact was 0.02. The relative error between the physical angle of repose and the simulated angle was 3.27%, indicating that it is feasible to apply the simulation experiment instead of the physical one. It offers insights into cotton stalk contact parameter settings and film-stalk separation in the simulation.

DNA methylation differences in Alzheimer’s disease have been previously reported, although the interpretation of the differences is unclear. Here, the authors performed epigenome-wide meta-analyses of DNA methylation in blood and brain, and developed a methylation-based risk prediction model for AD.

Conflict between local state and churches in China has increased both in number and intensity in recent years due to the Chinese Communist Party’s (CCP) tightened regulation and control over religious affairs and religious groups. Drawing on the theoretical insight of the positive function of social conflict proposed by Coser and the empirical findings in China, this paper tries to decode the impact of China’s religious policies on state–church interaction under Xi Jinping’s rule. It finds that the overall impacts of state intensified control over religions are twofold. On the one hand, state intervention paradoxically serves as a facilitating factor to enhance religious group’s internal cohesion, reinforce their group identity and help them reflect on and change their survival and development strategies. On the other hand, increased state control at the same time generates an unpleasant outcome that is not beneficial for a peaceful state–church interaction.

In this study, stable sodium chlorite solution and water-borne polyurethane (WPU) were mixed to prepare a novel antibacterial film with sustained-release properties via a solvent casting method. For the first time, carboxyl in WPU was used as the activator to react with ClO− to produce gaseous ClO2 under the trigger of moisture and without any other acid reagent. The results showed that the film had excellent antibacterial effect. However, as the content of stable ClO− increased, the mechanical strength and thermal stability of the film decreased, and its surface morphology showed irregular protrusions. In addition, the slow-release mechanism of the film with time under different temperatures was studied, whereby the release amount of the film was noted to be affected by temperature. This study explored the development of food packaging with efficient antibacterial activity and sustained-release performance without the use of acid reagents.

Abstract Sex is an important factor that contributes to the clinical and biological heterogeneities in Alzheimer’s disease (AD), but the regulatory mechanisms underlying sex disparity in AD are still not well understood. DNA methylation is an important epigenetic modification that regulates gene transcription and is known to be involved in AD. We performed the first large-scale sex-specific meta-analysis of DNA methylation differences in AD neuropathology, by re-analyzing four recent epigenome-wide association studies totaling more than 1000 postmortem prefrontal cortex brain samples using a uniform analytical pipeline. For each cohort, we employed two complementary analytical strategies, a sex-stratified analysis that examined methylation-Braak stage associations in male and female samples separately, and a sex-by-Braak stage interaction analysis that compared the magnitude of these associations between different sexes. Our analysis uncovered 14 novel CpGs, mapped to genes such as TMEM39A and TNXB that are associated with the AD Braak stage in a sex-specific manner. TMEM39A is known to be involved in inflammation, dysregulated type I interferon responses, and other immune processes. TNXB encodes tenascin proteins, which are extracellular matrix glycoproteins demonstrated to modulate synaptic plasticity in the brain. Moreover, for many previously implicated genes in AD neuropathology, such as MBP and AZU1, our analysis provided the new insights that they were predominately driven by effects in only one sex. These sex-specific DNA methylation differences were enriched in divergent biological processes such as integrin activation in females and complement activation in males. Our study implicated multiple new loci and biological processes that affected AD neuropathology in a sex-specific manner.

A high-speed vibratory bowl feeder is a key equipment of the optical detection of light emitting diode (LED) chips. Addressing the stationarity-losing problem induced by transporting small-size and light-weight LED chips, this study designs a vibratory bowl feeder for the high-speed detection of small LED chips based on theoretical and numerical analyses. To understand the influence of the structural parameters of the feeder on its performance, we create a mathematical model of the part’s behavior base on the Hertz-Mindlin contact theory. The numerical model indicates that the property of the part, the track angle and the friction coefficient of the track are the main factors that affect the behavior of the part in the feeding process. Through the discrete element method (DEM) simulation, we observe the part behavior under different track angles and friction coefficients of the feeder. The motion stationary of the LED chip is evaluated by its standard deviation (STD) of velocity and hopping height. Thus, we can appropriately determine these parameters of the vibratory feeder in order to get the optimal feeding performance. Finally, an experimental platform of the LED chip detection device is built to verify the performance of the vibratory bowl feeder. The experimental results show that the performance of the feeder was in good agreement with the simulation results. With the theoretical analysis and experimental verification, the vibratory bowl feeder was successfully implemented for LED transportation and reached a high feeding velocity of 1516.5 pieces/min at the working frequency of 223 Hz.

Servo systems driven by a permanent magnet linear synchronous motor (PMLSM) are often affected by uncertain disturbances, such as magnetic resistance, friction, and external disturbances, which increase tracking errors and reduce motion accuracy. Traditional control methods may have difficulty to achieve satisfactory control performance in terms of tracking accuracy and disturbance rejection. In this paper, we propose an internal model control PID method based on a model linear extended state observer, which is termed as IMC-PID-MLESO method. With this method, the nominal model parameters of the PMLSM servo system are obtained via system identification. The model linear extended state observer (MLESO), with known parameter information, is designed to improve the estimation accuracy for the system states and total unknown uncertainties. As the uncertainties are compensated in the feedback control law, the PMLSM servo system model is transformed into a known nominal model. Based on the nominal model, the IMC-PID feedback controller is designed to ensure satisfactory performance on disturbance rejection and tracking error reduction. Simulation and experimental results show that the IMC-PID-MLESO method can effectively improve the position tracking accuracy of the PMLSM servo system and rapidly suppress the system disturbance.

Previous studies have identified DNA methylation changes in Alzheimer’s disease. Here the authors perform a meta-analysis of DNA methylation datasets to identify epigenetic correlates of Alzheimer’s disease in the prefrontal cortex.

The synchronization error of a dual-motor system will seriously affect the motion profile accuracy. To solve this problem, an adaptive fractional-order anti-saturation synchronous control method based on fractional-order frequency-domain control theory is proposed in this paper. On the one hand, the proposed method performs a compensation on the closed-loop feedback control loop to unify the frequency-domain characteristics for a dual-motor system. With the frequency-domain characteristics’ unification module, the dual-motor system will have the same response performance regarding the input signal. On the other hand, considering that the nonlinear problem of control voltage saturation will also cause the asynchronization problem of the dual-motor system, the proposed method involves an adaptive fractional-order anti-saturation module to prevent voltage saturation and eliminate the nonlinear effects. The experimental results verify that the proposed method can accurately avoid the saturation effect and effectively reduce the synchronization error of the dual-motor system, with a root-mean-square synchronization error reduction of 80.974%. Hence, the proposed method provides an effective solution for the high-precision synchronous motion of a dual-motor system.

Iterative closest point algorithms suffer from non-convergence and local minima when dealing with cloud points with a different sampling density. Alternative global or semi-global registration algorithms may suffer from efficiency problem. This paper proposes a new registration algorithm through the differential topological singularity points (DTSP) based on the Helmholtz-Hodge decomposition (HHD), which is called DTSP-ICP method. The DTSP-ICP method contains two algorithms. First, the curvature gradient fields on surfaces are decomposed by the HHD into three orthogonal parts: divergence-free vector field, curl-free vector field, and a harmonic vector field, and then the DTSP algorithm is used to extract the differential topological singularity points in the curl-free vector field. Second, the ICP algorithm is utilized to register the singularity points into one aligned model. The singularity points represent the feature of the whole model, and the DTSP algorithm is designed to capture the nature of the differential topological structure of a mesh model. Through the singularity alignment, the DTSP-ICP method, therefore, possesses better performance in triangular model registration. The experimental results show that independent of sampling schemes, the proposed DTSP-ICP method can maintain convergence and robustness in cases where other alignment algorithms including the ICP alone are unstable. Moreover, this DTSP-ICP method can avoid the local errors of model registration based on Euclidean distance and overcome the computation insufficiencies observed in other global or semi-global registration publications. Finally, we demonstrate the significance of the DTSP-ICP algorithm's advantages on a variety of challenging models through result comparison with that of two other typical methods.

Glomerular endothelial surface layer (ESL) may play a role in the mechanisms of albuminuria in diabetic nephropathy, which lack evidence in vivo. The effects of high glucose on the passage of albumin across the glomerular ESL were analysed in streptozotocin-induced diabetic Sprague-Dawley rats for 4 weeks. Albuminuria and glomerular mesangial matrix were significantly increased in diabetic rats. The passage of albumin across the ESL, as measured by albumin-colloid gold particle density in the glomerular basement membrane (GBM), was increased significantly in diabetic rats. The thickness of the glomerular ESL, examined indirectly by infusing Intralipid into vessels using an electron microscope, was significantly decreased and the GBM exhibited little change in diabetic rats. In summary, the glomerular ESL may play a role in the pathogenesis of albuminuria in rats with early-stage diabetes.