Search Results (1,025)

To address the limitations of current prosthetic knees that lack personalized adaptability to users’ gait characteristics and walking speeds, this study proposes a personalized gait parameter prediction–based speed-adaptive control method for a hybrid active–passive intelligent prosthetic knee (HAPK). The proposed system integrates a perceptron-based model to predict individualized gait parameters by mapping anthropometric data and walking speed to key points of the knee trajectory. A fuzzy logic–based damping control for the swing phase and a position–torque control for the stance extension phase are developed to achieve real-time adaptation to different walking speeds and user-specific biomechanics. The hybrid actuation system combines hydraulic damping and motor torque assistance to ensure both compliance and power delivery across gait phases. Experimental results from variable-speed walking tests demonstrate that the proposed control method improves gait symmetry indices—reducing stance and swing asymmetries by approximately 30–38%—and achieves smoother, more natural gait transitions compared to traditional fixed-gait control strategies. These findings validate the effectiveness of the proposed approach in achieving continuous, personalized, and speed-consistent gait control for intelligent prosthetic knees. Full article

Cold-inducible RNA-binding protein (CIRP) is a critical molecule in the central nervous system (CNS) with functions that depend on its subcellular localization, exhibiting biphasic regulatory roles in both physiological and pathological processes. Under physiological conditions, intracellular cold-inducible RNA-binding protein (iCIRP) contributes to the maintenance of circadian rhythms by regulating the stability of core clock gene mRNAs and exerts neuroprotective effects during mild hypothermia by preserving the blood–brain barrier and inhibiting apoptosis. Pathologically, extracellular cold-inducible RNA-binding protein (eCIRP) functions as a damage-associated molecular pattern (DAMP) that drives neuroinflammation and brain injury. In ischemic stroke (IS), eCIRP promotes neutrophil extracellular trap (NET) formation and increases microglial activity via the Toll-like receptor 4 (TLR4) pathway. In cerebral ischemia–reperfusion (I/R) injury, eCIRP activates oxidative stress and the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome through the TLR4 axis, exacerbating mitochondrial damage. In intracerebral hemorrhage (ICH), eCIRP further amplifies inflammation via the interleukin-6 receptor (IL-6R)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. In traumatic brain injury (TBI), eCIRP activates the endoplasmic reticulum stress pathway, intensifying apoptosis. In Alzheimer’s disease (AD), eCIRP regulates tau phosphorylation and β-amyloid (Aβ) metabolism and may mediate the link between alcohol exposure and AD pathology. Preclinical studies indicate that serum eCIRP levels correlate with IS and ICH severity, highlighting its potential as a biomarker. This systematic review elucidates the mechanisms of CIRP in CNS diseases, providing insights for understanding and preventing conditions such as IS, cerebral I/R injury, ICH, TBI, and AD. Full article

The fractional Langevin equation is used to analyze the erratic motion of a particle in a complex environment. Hydrodynamic backflows and restoring harmonic forces can work concurrently on the probe particle in addition to the constraints imposed by the complex environment, whose characteristics are represented in the friction force the particle encounters. The friction force, which is used for the modelling, corresponds to a damped oscillating function and it is expressed by a one-parameter Mittag-Leffler function. Analytical solutions for the relaxation functions are extracted, and through them observables like the position autocorrelation function, velocity autocorrelation function and mean square displacement are explicitly given. The competition between hydrodynamic fluctuations and frictional forces establishes a memory whose time scale is larger than the diffusional time scale, and during this time window the motion of the particle is superdiffusive. Full article

Tissue decellularization aims to obtain bioscaffolds for regenerative applications by removing all cellular components while preserving the extracellular matrix (ECM) architecture. Although decellularization removes the majority of linear nuclear DNA (nDNA), residual amounts remain detectable. However, the fate of circular mitochondrial DNA (mtDNA) after decellularization has not yet been reported. Cell death or injury can cause the release of mtDNA, which is resistant to breakdown by exonucleases. Extracellular mtDNA acts as a damage-associated molecular pattern (DAMP) that can trigger immune responses. The aim of this study is to assess the presence of residual mtDNA in the liver, bile duct, and vascular scaffolds after decellularization and whether this causes inflammatory responses in macrophages. Decellularized tissues showed a marked reduction in total DNA content well below the threshold of 50 ng/mg tissue. However, in liver and vascular scaffolds, a relative increase in the mtDNA:nDNA ratio was detected in the remnant DNA fraction. Residual mtDNA in bioscaffolds acted as DAMPs causing macrophage activation, as shown by increased cell proliferation and cytokine production. Strategies to further reduce remnant mtDNA were tested. We found that treatment with the endonuclease enzyme HpaII was effective in degrading residual mtDNA. Importantly, mtDNA removal resulted in a significantly reduced macrophage activation. In conclusion, our study shows that mtDNA is relatively resistant to the decellularization procedure and can act as a DAMP in bioscaffolds. This underscores the importance of removing mtDNA from decellularized bioscaffolds to improve the immunocompatibility for biomedical applications. Full article

Background: Acquired cholesteatoma is a chronic inflammatory middle ear disease characterized by keratinizing squamous epithelium overgrowth and bone erosion. While the upregulation of pattern-recognition receptor (PRR) signaling has been consistently observed, it remains unclear whether this reflects a secondary response to microbial infection or a primary dysfunction driven by genetic predisposition. Methods: Using the UK Biobank, we analyzed 678 individuals with cholesteatoma (ICD-10: H71) among 502,164 participants. Candidate genes implicated in cholesteatoma-related inflammatory pathways (n = 17) were selected, and 147 polymorphisms were studied. Gene-specific genetic risk scores (GRSs) were calculated for cholesteatoma patients (GRSchol) and the general UK Biobank population (GRSpop). The difference (ΔGRSchol-GRSpop) was used to assess the relative contribution of each gene. Results: Genes with the highest ΔGRS were IL6, TREM1, IL1R1, IL1A, HIF1A, ID1, RAGE, and TNFA. These genes represent key downstream mediators and amplifiers of PRR signaling rather than the receptors themselves. Variants in cytokine genes (IL6, IL1R1, IL1A, and TNFA) may enhance inflammatory signaling and bone resorption; Trem1 amplifies TLR responses; RAGE sustains sterile DAMP-driven inflammation, while HIF1A and ID1 implicate hypoxia, tissue remodeling, and keratinocyte proliferation in disease persistence. Conclusions: Our findings suggest that cholesteatoma pathogenesis may not be driven solely by microbial activation of PRRs but rather by genetic variants that amplify and sustain downstream inflammatory responses. This supports a model of cholesteatoma as a disease of self-perpetuating inflammation triggered by diverse stressors, including microbial and non-microbial insults. These insights may inform preventive strategies targeting environmental stressors, as well as therapeutic approaches using biologics to interrupt chronic inflammatory amplification in cholesteatoma. Full article

Synthetic chemicals, such as fertilizers and pesticides, are widely used in agriculture to improve soil fertility and to control weeds, pests and diseases. Numerous studies have highlighted the negative effects of these chemicals on the soil environment. In contrast, during vermicomposting, earthworms generate numerous beneficial outcomes. This study aimed to screen antagonistic bacteria found after vermicomposting for their potential to inhibit the pre-emergence damping-off of tomato seedlings caused by Rhizoctonia solani. Using a dual culture method, 85 bacterial isolates were screened, three of which demonstrated antagonistic activity against R. solani. Molecular characterization based on 16S ribosomal RNA identified the bacterial isolates as Bacillus subtilis (NOAC.B77), Bacillus vallismortis (NOAC.B42), and Bacillus cereus (NOAC.B17). The strains NOAC.B77 and NOAC.B42 exhibited the most significant inhibitory effects on the mycelial growth of R. solani, with inhibition levels of 80.8% and 79.2%, respectively. In greenhouse trials, only 13% of the Inoculated, Unprotected Control tomato seedlings emerged, i.e., the R. solani inoculum caused an 87% level of preemergence damping off. In contrast, after treatment with the bacterial strains NOAC.B77 and NOAC.B42, tomato seedling emergence was not significantly different from the Uninoculated Control. These results suggest that the bacterial strains NOAC.B77 and NOAC.B42 could be commercialized as biological agents to control damping-off of tomato seedlings under greenhouse conditions. Full article

Bio-inspired flow-sensing and actuation mechanisms offer a promising path for enhancing the stability of flapping-wing flying robots (FWFRs) operating in dynamic and noisy environments. This study introduces a bio-inspired sensing and actuation feather unit (SAFU) that mimics the covert feathers of falcons and serves simultaneously as a distributed flow sensor and an adaptive actuation element. Each electromechanical feather (EF) passively detects airflow disturbances through deflection and actively modulates its flaps through an embedded actuator, enabling real-time aerodynamic adaptation. A reduced-order bond-graph model capturing the coupled aero-electromechanical dynamics of the FWFR wing and SAFU is developed to provide a physics-based training environment for a proximal policy optimization (PPO) based reinforcement learning controller. Through closed-loop interaction with this environment, the PPO policy autonomously learns control actions that regulate feather displacement, reduce airflow-induced loads, and improve dynamic stability without predefined control laws. Simulation results show that the PPO-driven SAFU achieves fast, well-damped responses with rise times below 0.5 s, settling times under 1.4 s, near-zero steady-state error across varying gust conditions and up to 50% alleviation of airflow-induced disturbance effects. Overall, this work highlights the potential of bio-inspired sensing-actuation architectures, combined with reinforcement learning, to serve as a promising solution for future flapping-wing drone designs, enabling enhanced resilience, autonomous flow adaptation, and intelligent aerodynamic control during operations in gusts. Full article

Controlled local hyperthermia supports postoperative wound healing in liver surgery by stimulating metabolism, angiogenesis, and immune responses through the induction of heat shock proteins (HSPs) and modulation of Damage-Associated Molecular Patterns (DAMPs). This study evaluates the impact of thermal modulation on immune processes during abdominal wound repair, specifically analyzing the role of HSPs and immune activation pathways. A narrative review of the literature from 2010 to 2025 was conducted to summarize molecular mechanisms regarding temperature, HSP activation, cytokine expression, and DAMPs, excluding studies conducted solely in animal models. The results indicate that precise local hyperthermia in postoperative abdominal wounds activates HSPs as well as inflammasome and Toll-like receptor (TLR) pathways, modulating immune and cytokine responses depending on the type and depth of tissue injury. Consequently, such thermoimmunomodulation stabilizes immune cell functions, optimizes the balance between inflammation and regeneration, and minimizes the risk of postoperative complications to support effective wound healing. Full article

As wind power is a core component of sustainable energy systems, ensuring its stable grid integration is critical to advancing the 2030 Agenda for Sustainable Development, particularly in increasing the share of renewable energy, reducing carbon emissions, and promoting energy system sustainability. During the system frequency stability regulation, the active power output of wind farms undergoes continuous changes, which can affect the stable operation of the grid-connected system. To address this issue, this paper proposes an active power optimization allocation strategy of multiple wind turbines considering stability improvement. First, an equivalent impedance model of the wind farm grid-connected system was established, taking into account the differences in active power output and terminal impedance of wind turbines. Based on this model, the mechanisms by which different active power outputs and terminal impedances affect the system’s stability margin were analyzed, revealing the matching mechanism between wind turbine output and terminal impedance required to meet stability requirements; second, with the objective of maximizing the system damping ratio stability margin while balancing power constraints and wind turbine frequency regulation capability constraints, a multi-turbine frequency regulation power optimization model considering stability enhancement was established. The particle swarm optimization algorithm is employed to solve for the optimal frequency regulation power allocation scheme for each wind turbine. Finally, the effectiveness of the proposed strategy in improving the stability of the frequency regulation process in wind farms was verified through simulation examples. The proposed strategy enhances the reliability of wind power integration, reduces the risk of curtailment or disconnection of clean energy, and provides a technical tool for sustainable energy transition. Full article

Endothelial cell (EC) barrier integrity is tightly regulated by the activity of the non-muscle myosin light chain kinase (nmMLCK) under diverse pathological inflammatory conditions (pneumonia, sepsis) and exposure to mechanical stress. Inflammatory stimuli, including lipopolysaccharide (LPS), cytokines, and damage-associated molecular patterns (DAMPs), increase EC permeability through nmMLCK-dependent EC paracellular gap formation. However, the exact mechanisms by which nmMLCK regulates vascular barrier dysfunction in acute lung injury (ALI) remain incompletely understood. We hypothesized that inflammation-induced ROS results in the peroxynitrite-mediated nitration of nmMLCK that contributes to EC barrier disruption. Human lung EC exposure to either the peroxynitrite donor, SIN-1, or to LPS, triggered significant nmMLCK nitration, which was abolished by the oxidant scavenger, MnTMPyP. Mass spectrometry of SIN-1-treated nmMLCK identified multiple nitrated tyrosines. Nitration of Y1410 proved a critical PTM as site-directed substitution with alanine (Y1410A) abolished both SIN-1- and LPS-induced nmMLCK nitration. nmMLCK nitration disrupts wild-type nmMLCK interaction with Kindlin-2, a cytoskeletal regulator of vascular barrier stability, whereas EC transfected with the Y1410A nmMLCK mutant exhibited preserved Kindlin-2 binding, reflected by alterations in trans-EC electrical resistance (TEER). Consistent with these observations, LPS-challenged murine lungs displayed enhanced nmMLCK nitration and diminished nmMLCK-Kindlin-2 association. Functionally, SIN-1 markedly impaired EC barrier integrity (TEER), which was not observed in ECs expressing the Y1410A mutant. Together, these findings suggest that nmMLCK nitration at Y1410 is a critical molecular mechanism contributing to vascular leakage, highlighting this modification as a potential therapeutic target to reduce inflammation-induced vascular permeability. Given nmMLCK’s established role in barrier regulation, we hypothesized that LPS-induced peroxynitrite formation may promote the nitration of nmMLCK tyrosine residues: a PTM that potentially contribute to nmMLCK’s regulation of EC barrier integrity. Full article

This study investigated the dynamic behavior of AA7075 plates joined by Friction Stir Welding (FSW), focusing on the influence of key process parameters, rotation, and traverse speeds, on the resulting dynamic characteristics. Experimental Modal Analysis (EMA) was performed under free boundary conditions to determine resonance frequencies, mode shapes, and damping ratios, revealing that an increase in traverse speed consistently led to a decrease in natural frequencies across most modes, thereby indicating reduced joint stiffness attributed to insufficient heat input. Furthermore, localized weld defects caused significant damping variations, particularly in low-order modes. To complement the experimental findings and enable simultaneous, multi-output prediction of these coupled dynamic parameters, a Co-Active Neuro-Fuzzy Inference System (CANFIS) model was developed. The CANFIS architecture utilized spindle speed and feed rate as inputs to predict natural frequency and damping ratio for multiple vibration modes as tightly coupled outputs. The trained model demonstrated strong agreement and high predictive accuracy against the EMA experimental data, with convergence analysis confirming its stable learning and excellent generalization capability. The successful integration of EMA and CANFIS establishes a robust hybrid framework for both physical interpretation and intelligent, coupled prediction of the dynamic behavior of FSW-welded AA7075 plates. Full article

To address the issue of negative damping instability easily induced by DC/DC converters under constant power load (CPL) in DC microgrids and to enhance the control robustness of the system under uncertainties such as parameter perturbations, this paper designs a controller based on the linear active disturbance rejection control (LADRC) theory. Firstly, by establishing an equivalent model of the DC microgrid with CPL, the intrinsic relationship between the equivalent incremental admittance of the hybrid load and the system damping is revealed. Subsequently, treating the nonlinear characteristics of the CPL and model parameter variations as external disturbances, the linear extended state observer (LESO) is employed to estimate and compensate for the total system disturbance in real time. This effectively eliminates the risk of negative damping instability caused by the CPL and enhances the system’s robustness against parameter variations. Then, theoretical analysis is conducted from three perspectives, the convergence of disturbance estimation error, the stability of the closed-loop system, and robustness against parameter variations, thereby ensuring the reliability of the proposed control strategy. Finally, the proposed control strategy is validated through simulations and experiments. The results confirm that, even in the presence of negative damping effects and parameter variations, the strategy can effectively maintain fast tracking and stable control of the output voltage. Full article

Non-long terminal repeat (Non-LTR) retrotransposons are mobile genetic elements that replicate through a “copy-and-paste” mechanism, enabling their expansion within the genome. Aberrant activation of these elements can induce genomic instability, elicit cellular stress responses, and activate inflammasome signaling, leading to tissue injury and disease. The central process of sterile inflammation involves the release and recognition of damage-associated molecular patterns (DAMPs), endogenous molecules that initiate inflammatory responses and form a common basis for many sterile inflammatory disorders. Recent studies have identified non-LTR retrotransposons as key endogenous triggers of DAMP-like signaling that drive sterile inflammation in both neuronal and non-neuronal tissues, contributing to the development of neurodegenerative and other chronic inflammatory diseases. In this review, we summarize recent advances in understanding how non-LTR retrotransposons, particularly LINE and SINE elements, influence sterile inflammation and disease pathogenesis. We highlight how their mobilization reshapes genomic architecture and gene regulation, and how the resulting signaling cascades promote chronic inflammation, immune dysregulation, and tissue injury. We also discuss emerging therapeutic strategies aimed at suppressing retrotransposon activity or interrupting downstream inflammatory signaling for treating sterile inflammation-related diseases. Full article

Due to the negative resistance effect of power electronic devices, power systems with a high proportion of renewable energy face a significant resonance risk. To address this, this paper proposes a resonance-suppression strategy for high-penetration renewable energy systems based on an active amplitude and phase corrector (APC). Firstly, by considering its internal dynamics and complete control loops, the impedance model of the APC is derived. Next, the similarities and differences between resonance stability and harmonic resonance are analyzed using the s-domain and frequency-domain admittance matrices, concluding that resonance suppression for low-damping s-domain modes can be handled in the frequency domain. Then, a supplementary APC control strategy in the abc-frame is proposed, which improves impedance magnitude at specific frequencies while keeping the phase almost unchanged. Finally, the proposed strategy is validated through case studies on an offshore wind power system in Zhejiang Province. Full article

Grid-forming converters have gained significant attention for their ability to form grid voltage and provide essential grid-supportive services. However, managing harmonics generated by nonlinear loads remains a critical challenge in weak grids. A single grid-forming converter active power filter offers limited compensation capacity, and under heavy nonlinear loading its performance is restricted by converter ratings, leading to reduced stability margins, higher harmonic distortion, and weakened voltage/frequency regulation. To overcome these limitations, this paper presents a novel distributed control approach for multiple-parallel grid-forming converters active power filters that integrates voltage and frequency regulation with scalable harmonic attenuation. The proposed method extracts harmonic components at the point of common coupling and generates harmonic voltage commands to each unit so the parallel units collectively create a near short-circuit impedance for harmonics, preventing harmonic currents from propagating into the grid. Beyond improved harmonic performance, the multi-unit system enhances effective inertia, damping, and short-circuit capacity while avoiding complex parameter tuning, enabling a simple and scalable deployment. Simulation results demonstrate effective harmonic attenuation at the point of common coupling and accurate active/reactive power sharing. Full article