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Search Results (7,659)

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Keywords = control “by disturbance”

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16 pages, 1197 KiB  
Article
Is There a “Non-Motor Effect” of Botulinum Toxin Treatment in Cervical Dystonia in Addition to Its Effects on Motor Symptoms?
by Małgorzata Dudzic, Anna Pieczyńska, Artur Drużdż, Anna Rajewska and Katarzyna Hojan
Toxins 2025, 17(8), 396; https://doi.org/10.3390/toxins17080396 (registering DOI) - 6 Aug 2025
Abstract
The efficacy of botulinum toxin A (BoNT) in alleviating motor symptoms of cervical dystonia (CD) has been well established, and it is the treatment of choice in this disease. Lately, the effect of BoNT on non-motor symptoms (NMS) such as cognitive function, depression, [...] Read more.
The efficacy of botulinum toxin A (BoNT) in alleviating motor symptoms of cervical dystonia (CD) has been well established, and it is the treatment of choice in this disease. Lately, the effect of BoNT on non-motor symptoms (NMS) such as cognitive function, depression, anxiety, pain, and sleep disturbance has been observed in patients with CD. A comprehensive clinical and functional assessment of motor (dystonia severity, gait) and non-motor symptoms (cognitive functions, depression, anxiety, sleep, and pain) has been performed in a total of 34 adult patients with cervical dystonia before and after BoNT treatment. Results have also been compared to a control group. Significant improvements in the scales assessing dystonia severity have been observed, which is in line with previous studies on the effect of BoNT on motor symptoms in dystonia. Interestingly, the results also clearly indicate that BoNT has a positive effect on NMS. Among the studied non-motor domains, depression and cognitive functions improved the most after the treatment procedure. The study highlights the potential of BoNT to positively influence non-motor symptoms in patients with cervical dystonia, although its effect on various NMS is not equal. Full article
(This article belongs to the Special Issue Advances in the Treatment of Movement Disorders with Botulinum Toxins)
21 pages, 8352 KiB  
Article
Research on Vibration Characteristics of Electric Drive Systems Based on Open-Phase Self-Fault-Tolerant Control
by Wenyu Bai, Yun Kuang, Zhizhong Xu, Yawen Wang and Xia Hua
Appl. Sci. 2025, 15(15), 8707; https://doi.org/10.3390/app15158707 (registering DOI) - 6 Aug 2025
Abstract
This paper presents an electromechanical coupling model integrating an equivalent magnetic network (EMN) model of a dual three-phase permanent magnet synchronous motor (DTP-PMSM) with the dynamic model of a helical planetary gear transmission system. Using this model, this study analyzes the dynamic characteristics [...] Read more.
This paper presents an electromechanical coupling model integrating an equivalent magnetic network (EMN) model of a dual three-phase permanent magnet synchronous motor (DTP-PMSM) with the dynamic model of a helical planetary gear transmission system. Using this model, this study analyzes the dynamic characteristics of an electric drive system, specifically motor phase current, electromagnetic torque, and gear meshing force, under self-fault-tolerant control strategies. Simulation and experimental results demonstrate that the self-fault-tolerant control strategy enables rapid fault tolerance during open-phase faults, significantly reducing system fault recovery time. Meanwhile, compared to the open-phase faults conditions, the self-fault-tolerant control effectively suppresses most harmonic components within the system; only the second harmonic amplitude of the electromagnetic torque exhibited an increase. This harmonic disturbance propagates to the gear system through electromechanical coupling, synchronously amplifying the second harmonic amplitude in the gear system’s vibration response. This study demonstrates that self-fault-tolerant control strategies significantly enhance the dynamic response performance of the electric drive system under open-phase faults conditions. Furthermore, this study also investigates the electromechanical coupling mechanism through which harmonics generated by this strategy affect the gear system’s dynamic response, providing theoretical support for co-optimization electromechanical coupling design and fault-tolerant control in high-reliability electric drive transmission systems. Full article
(This article belongs to the Section Mechanical Engineering)
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11 pages, 2711 KiB  
Article
Finite Element Dynamic Modeling of Smart Structures and Adaptive Backstepping Control
by Zhipeng Xie, Dachang Zhu, Zhenzhang Liu, Yun Long and Fangyi Li
Mathematics 2025, 13(15), 2531; https://doi.org/10.3390/math13152531 - 6 Aug 2025
Abstract
Smart structures with topological configurations that integrate perception and actuation have complex geometric features. The simplification of these features can lead to deviations in dynamic characteristics, making it difficult to establish an accurate dynamic model. Uncertainties, such as material nonlinearity, hysteresis in elastic [...] Read more.
Smart structures with topological configurations that integrate perception and actuation have complex geometric features. The simplification of these features can lead to deviations in dynamic characteristics, making it difficult to establish an accurate dynamic model. Uncertainties, such as material nonlinearity, hysteresis in elastic deformation, and external disturbances, affect the trajectory tracking accuracy of the smart structure’s actuation function. This paper proposes a modeling method that combines finite element unit bodies and orthogonal characteristic mode reduction to construct an accurate dynamic model of the smart structure and design an adaptive backstepping controller. Nonlinear dynamic equations are derived through a finite element analysis of the structure, and the orthogonal characteristic mode reduction method is employed to reduce computational complexity while ensuring model accuracy. An adaptive backstepping controller is designed to mitigate model uncertainties and achieve precise trajectory tracking control. Simulation and experimental results demonstrate that the proposed method can effectively handle the nonlinearity and modeling errors of smart structures, achieving high-precision trajectory tracking and verifying the accuracy of the dynamic model as well as the robustness of the controller. Full article
25 pages, 10639 KiB  
Article
Sliding Mode Control of the MY-3 Omnidirectional Mobile Robot Based on RBF Neural Networks
by Huaiyong Li, Changlong Ye, Song Tian and Suyang Yu
Machines 2025, 13(8), 695; https://doi.org/10.3390/machines13080695 - 6 Aug 2025
Abstract
Omnidirectional mobile robots have gained extensive application across diverse fields due to their exceptional maneuverability and adaptability in confined spaces. However, structural and systemic uncertainties significantly compromise motion accuracy. To enhance motion control precision, this paper proposes a sliding mode control (SMC) method [...] Read more.
Omnidirectional mobile robots have gained extensive application across diverse fields due to their exceptional maneuverability and adaptability in confined spaces. However, structural and systemic uncertainties significantly compromise motion accuracy. To enhance motion control precision, this paper proposes a sliding mode control (SMC) method integrated with a radial basis function (RBF) neural network. The approach aggregates model uncertainties, nonlinear dynamics, and unknown disturbances into a composite disturbance term. An RBF neural network is employed to approximate this disturbance, with compensation embedded within the SMC framework. An online adaptive law for neural network optimization is derived using the Lyapunov stability theorem, thereby improving the disturbance rejection capability. Comparative simulations and experiments validate the proposed method against modern control strategies. Results demonstrate superior tracking performance and robustness, significantly enhancing trajectory tracking accuracy for the MY3 wheeled omnidirectional mobile robot. Full article
(This article belongs to the Section Robotics, Mechatronics and Intelligent Machines)
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20 pages, 394 KiB  
Article
Feedback Linearization for a Generalized Multivariable T-S Model
by Basil Mohammed Al-Hadithi, Javier Blanco Rico and Agustín Jiménez
Electronics 2025, 14(15), 3129; https://doi.org/10.3390/electronics14153129 - 6 Aug 2025
Abstract
This study presents a novel optimal fuzzy logic control (FLC) strategy based on feedback linearization for the regulation of multivariable nonlinear systems. Building upon an enhanced Takagi–Sugeno (T-S) model previously developed by the authors, the proposed method incorporates a refined parameter-weighting scheme to [...] Read more.
This study presents a novel optimal fuzzy logic control (FLC) strategy based on feedback linearization for the regulation of multivariable nonlinear systems. Building upon an enhanced Takagi–Sugeno (T-S) model previously developed by the authors, the proposed method incorporates a refined parameter-weighting scheme to optimize both local and global approximations within the T-S framework. This approach enables improved selection and minimization of the performance index. The effectiveness of the control strategy is validated through its application to a two-link serial robotic manipulator. The results demonstrate that the proposed FLC achieves robust performance, maintaining system stability and high accuracy even under the influence of noise and load disturbances, with well-damped system behavior and negligible steady-state error. Full article
(This article belongs to the Section Systems & Control Engineering)
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26 pages, 10899 KiB  
Article
Investigation of Pulse Power Smoothing Control Based on a Three-Phase Interleaved Parallel Bidirectional Buck-Boost DC–DC Converter
by Jingbin Yan, Tao Wang, Feiruo Qin and Haoxuan Hu
Symmetry 2025, 17(8), 1247; https://doi.org/10.3390/sym17081247 - 6 Aug 2025
Abstract
To address the issues of DC-side voltage fluctuation and three-phase current distortion in rectifier systems under pulsed load conditions, this paper proposes a control strategy that integrates Model Predictive Control (MPC) with a Luenberger observer for the Power Pulsation Buffer (PPB). The observer [...] Read more.
To address the issues of DC-side voltage fluctuation and three-phase current distortion in rectifier systems under pulsed load conditions, this paper proposes a control strategy that integrates Model Predictive Control (MPC) with a Luenberger observer for the Power Pulsation Buffer (PPB). The observer parameters are adaptively tuned using a gradient descent method. First, the pulsed current generated by the load is decomposed into dynamic and average components, and a mathematical model of the PPB is established. Considering the negative impact of DC voltage ripple and lumped disturbances such as parasitic parameters on model accuracy, a Luenberger observer is designed to estimate these disturbances. To overcome the dependence of traditional Luenberger observers on empirically tuned gains, an adaptive gradient descent algorithm based on gradient direction consistency is introduced for online gain adjustment. Simulation and experimental results demonstrate that the proposed control strategy—combining the Luenberger observer with gradient descent and MPC—effectively reduces current tracking overshoot and improves tracking accuracy. Furthermore, it enables sustained decoupling of the PPB from the system, significantly mitigating DC-side voltage ripple and three-phase current distortion under pulsed load conditions, thereby validating the effectiveness of the proposed approach. Full article
(This article belongs to the Section Engineering and Materials)
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22 pages, 6784 KiB  
Article
A Second-Order LADRC-Based Control Strategy for Quadrotor UAVs Using a Modified Crayfish Optimization Algorithm and Fuzzy Logic
by Kelin Li, Guangzhao Wang and Yalei Bai
Electronics 2025, 14(15), 3124; https://doi.org/10.3390/electronics14153124 - 5 Aug 2025
Abstract
To enhance the rapid and stable tracking of a specified trajectory by quadcopter drones, while ensuring a degree of resistance to external wind disturbances, this paper proposes an integrated control strategy that combines an optimization algorithm and fuzzy control. In this system, both [...] Read more.
To enhance the rapid and stable tracking of a specified trajectory by quadcopter drones, while ensuring a degree of resistance to external wind disturbances, this paper proposes an integrated control strategy that combines an optimization algorithm and fuzzy control. In this system, both the position and attitude loops utilize second-order Linear Active Disturbance Rejection Control (LADRC) controllers, supplemented by fuzzy controllers. These controllers have been optimized using a modified crayfish optimization algorithm (MCOA), resulting in a dual-closed-loop control system. In comparisons with both the dual-closed-loop LADRC controller and the dual-closed-loop fuzzy control LADRC controller, the proposed method reduces the rise time by 52.87% in the X-channel under wind-free conditions, reduces the maximum trajectory tracking error by 86.37% under wind-disturbed conditions, and reduces the ITAE exponent by 66.2%, which demonstrates that the newly designed system delivers excellent tracking speed and accuracy along the specified trajectory. Furthermore, it remains effective even in the presence of external disturbances, it can reliably maintain the target position and the attitude angle, demonstrating strong resistance to interference and stability. Full article
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17 pages, 294 KiB  
Review
Coffee’s Impact on Health and Well-Being
by Ryan C. Emadi and Farin Kamangar
Nutrients 2025, 17(15), 2558; https://doi.org/10.3390/nu17152558 - 5 Aug 2025
Abstract
Coffee is one of the most widely consumed beverages globally, with over 60% of Americans drinking it daily. This review examines coffee’s multifaceted impact on health and well-being, drawing on decades of research. Overall, the consensus is that moderate coffee intake is more [...] Read more.
Coffee is one of the most widely consumed beverages globally, with over 60% of Americans drinking it daily. This review examines coffee’s multifaceted impact on health and well-being, drawing on decades of research. Overall, the consensus is that moderate coffee intake is more beneficial than harmful across a wide range of health outcomes. Numerous large-scale, prospective cohort studies from around the world have consistently shown that moderate coffee consumption—typically three to five cups per day—is associated with reduced overall mortality and lower risk of major diseases such as cardiovascular diseases, diabetes, stroke, respiratory conditions, cognitive decline, and potentially several types of cancer, including liver and uterine cancers. Both caffeinated and decaffeinated coffee have shown benefits. The addition of sugar and cream to coffee may attenuate coffee’s positive health effects. Despite historical concerns, coffee consumption is not linked to increased risks of cancer, hypertension, or arrhythmia. However, some concerns remain. For pregnant women, coffee consumption should be limited to lower amounts, such that the daily intake of caffeine does not exceed 200 mg/day. Also, excessive caffeinated coffee intake may cause anxiety or sleep disturbances. Coffee’s health-promoting mechanisms include improved glucose balancing, increased physical activity, increased fat oxidation, improved lung function, and reduced inflammation. Beyond mortality and chronic diseases, coffee consumption affects many aspects of well-being: it supports hydration, boosts mental acuity, enhances physical performance, and may aid bowel recovery after surgery. While the field is well-studied via long-term observational cohorts, future research should focus on randomized controlled trials, Mendelian randomization studies, and granular analyses of coffee types and additives. Full article
(This article belongs to the Section Nutritional Epidemiology)
23 pages, 3121 KiB  
Article
Seasonal Changes in the Soil Microbiome on Chernozem Soil in Response to Tillage, Fertilization, and Cropping System
by Andrea Balla Kovács, Evelin Kármen Juhász, Áron Béni, Costa Gumisiriya, Magdolna Tállai, Anita Szabó, Ida Kincses, Tibor Novák, András Tamás and Rita Kremper
Agronomy 2025, 15(8), 1887; https://doi.org/10.3390/agronomy15081887 - 5 Aug 2025
Abstract
Soil microbial communities are crucial for ecosystem services, soil fertility, and the resilience of agroecosystems. This study investigated how long-term (31 years) agronomic practices—tillage, NPK fertilization, and cropping system—along with measured environmental variables influence the microbial biomass and its community composition in Chernozem [...] Read more.
Soil microbial communities are crucial for ecosystem services, soil fertility, and the resilience of agroecosystems. This study investigated how long-term (31 years) agronomic practices—tillage, NPK fertilization, and cropping system—along with measured environmental variables influence the microbial biomass and its community composition in Chernozem soil under corn cultivation. The polyfactorial field experiment included three tillage treatments ((moldboard (MT), ripped (RT), strip (ST)), two fertilization regimes (NPK (N: 160; P: 26; K: 74 kg/ha), and unfertilized control) and two cropping systems (corn monoculture and corn–wheat biculture). The soil samples (0–30 cm) were collected in June and September 2023. Microbial biomass and community structure were quantified using phospholipid fatty acid (PLFA) analysis, which allowed the estimation of total microbial biomass and community composition (arbuscular mycorrhizal (AM) fungi, fungi, Gram-negative (GN) and Gram-positive (GP) bacteria, actinomycetes). Our results showed that microbial biomass increased from June to September, rising by 270% in unfertilized plots and by 135% in NPK-fertilized plots, due to higher soil moisture. Reduced tillage, especially ST, promoted significantly higher microbial biomass, with biomass reaching 290% and 182% of that in MT plots in June and September, respectively. MT had a higher ratio of bacteria-to-fungi compared to RT and ST, indicating a greater sensitivity of fungi to disturbance. NPK fertilization lowered soil pH by about one unit (to 4.1–4.8) and reduced microbial biomass—by 2% in June and 48% in September—compared to the control, with the particular suppression of AM fungi. The cropping system had a smaller overall effect on microbial biomass. Full article
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18 pages, 861 KiB  
Article
Observer-Based Exponential Stability Control of T-S Fuzzy Networked Systems with Varying Communication Delays
by Hejun Yao and Fangzheng Gao
Mathematics 2025, 13(15), 2513; https://doi.org/10.3390/math13152513 - 5 Aug 2025
Abstract
This paper is concerned with the problem of dynamic output feedback exponential stability control of T-S fuzzy networked control systems (NCSs) with varying communication delays. First, with consideration of varying communication delays, a new model of the networked systems is established by using [...] Read more.
This paper is concerned with the problem of dynamic output feedback exponential stability control of T-S fuzzy networked control systems (NCSs) with varying communication delays. First, with consideration of varying communication delays, a new model of the networked systems is established by using the T-S fuzzy method, and a state observer is designed to estimate the unknown control disturbance. Then, a delay-dependent exponential stability criterion of closed-loop systems is derived by means of iterative technique and multiple augmented Lyapnov functionals and the linear matrix inequality (LMI) method. Furthermore, an observer-based controller is explicitly constructed to realize exponential stability control for this class of NCSs. An iterative algorithm is developed to compute the controller’s matrix by means of the Cone Complementarity Linearization Method (CCLM). Lastly, the validity and feasibility of the proposed exponential stability criterion are confirmed via a numerical simulation example. Full article
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33 pages, 640 KiB  
Review
Future Pharmacotherapy for Bipolar Disorders: Emerging Trends and Personalized Approaches
by Giuseppe Marano, Francesco Maria Lisci, Gianluca Boggio, Ester Maria Marzo, Francesca Abate, Greta Sfratta, Gianandrea Traversi, Osvaldo Mazza, Roberto Pola, Gabriele Sani, Eleonora Gaetani and Marianna Mazza
Future Pharmacol. 2025, 5(3), 42; https://doi.org/10.3390/futurepharmacol5030042 - 4 Aug 2025
Abstract
Background: Bipolar disorder (BD) is a chronic and disabling psychiatric condition characterized by recurring episodes of mania, hypomania, and depression. Despite the availability of mood stabilizers, antipsychotics, and antidepressants, long-term management remains challenging due to incomplete symptom control, adverse effects, and high relapse [...] Read more.
Background: Bipolar disorder (BD) is a chronic and disabling psychiatric condition characterized by recurring episodes of mania, hypomania, and depression. Despite the availability of mood stabilizers, antipsychotics, and antidepressants, long-term management remains challenging due to incomplete symptom control, adverse effects, and high relapse rates. Methods: This paper is a narrative review aimed at synthesizing emerging trends and future directions in the pharmacological treatment of BD. Results: Future pharmacotherapy for BD is likely to shift toward precision medicine, leveraging advances in genetics, biomarkers, and neuroimaging to guide personalized treatment strategies. Novel drug development will also target previously underexplored mechanisms, such as inflammation, mitochondrial dysfunction, circadian rhythm disturbances, and glutamatergic dysregulation. Physiological endophenotypes, such as immune-metabolic profiles, circadian rhythms, and stress reactivity, are emerging as promising translational tools for tailoring treatment and reducing associated somatic comorbidity and mortality. Recognition of the heterogeneous longitudinal trajectories of BD, including chronic mixed states, long depressive episodes, or intermittent manic phases, has underscored the value of clinical staging models to inform both pharmacological strategies and biomarker research. Disrupted circadian rhythms and associated chronotypes further support the development of individualized chronotherapeutic interventions. Emerging chronotherapeutic approaches based on individual biological rhythms, along with innovative monitoring strategies such as saliva-based lithium sensors, are reshaping the future landscape. Anti-inflammatory agents, neurosteroids, and compounds modulating oxidative stress are emerging as promising candidates. Additionally, medications targeting specific biological pathways implicated in bipolar pathophysiology, such as N-methyl-D-aspartate (NMDA) receptor modulators, phosphodiesterase inhibitors, and neuropeptides, are under investigation. Conclusions: Advances in pharmacogenomics will enable clinicians to predict individual responses and tolerability, minimizing trial-and-error prescribing. The future landscape may also incorporate digital therapeutics, combining pharmacotherapy with remote monitoring and data-driven adjustments. Ultimately, integrating innovative drug therapies with personalized approaches has the potential to enhance efficacy, reduce adverse effects, and improve long-term outcomes for individuals with bipolar disorder, ushering in a new era of precision psychiatry. Full article
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15 pages, 449 KiB  
Article
Association Between Rest–Activity Rhythm and 27-Hydroxycholesterol (27-OH) in Patients with Amnestic Mild Cognitive Impairment (aMCI)
by Seong Jae Kim, Jung Hie Lee, Jae-Won Jang, Minseo Choi and In Bum Suh
J. Clin. Med. 2025, 14(15), 5481; https://doi.org/10.3390/jcm14155481 - 4 Aug 2025
Abstract
Background/Objectives: Rest–activity rhythm (RAR) disturbances can contribute to aging and dementia via metabolic dysregulation. Hydroxycholesterol (OH) is thought to mediate the link between hypercholesterolemia and neurodegeneration. This study compared sleep and RAR parameters between amnestic mild cognitive impairment (aMCI) patients and normal [...] Read more.
Background/Objectives: Rest–activity rhythm (RAR) disturbances can contribute to aging and dementia via metabolic dysregulation. Hydroxycholesterol (OH) is thought to mediate the link between hypercholesterolemia and neurodegeneration. This study compared sleep and RAR parameters between amnestic mild cognitive impairment (aMCI) patients and normal controls (NCs), and examined their associations with plasma 27-OH levels, reflecting peripheral cholesterol metabolism. Methods In total, 18 aMCI patients (76.6 ± 6.1 years) and 21 NCs (70.4 ± 6.7 years) underwent five-day actigraphy and dim light melatonin onset assessment. Plasma 27-OH levels were measured via high-performance liquid chromatography-mass spectrometry. Generalized linear models (GLMs) were used to analyze the relationships between sleep, RAR, and 27-OH levels. Results: The aMCI group had significantly lower 27-OH levels and 27-OH/total cholesterol ratios (p < 0.05). GLM revealed that longer sleep onset latency (SOL) was associated with higher 27-OH levels in aMCI, distinguishing them from NCs. Additionally, in aMCI, longer SOL, lower sleep efficiency (SE), and higher fragmentation index (FI) were associated with an increased 27-OH/total cholesterol ratio (p < 0.05). Higher relative amplitude of RAR was linked to lower 27-OH levels across groups (p < 0.01), but RAR parameters showed no significant association with the 27-OH/total cholesterol ratio. Sleep disturbances, including prolonged SOL, reduced SE, and increased FI, were associated with altered peripheral cholesterol oxygenation in aMCI. Conclusions: Greater RAR amplitude correlated with lower 27-OH levels, regardless of cognitive status. These findings suggest that peripheral cholesterol oxygenation in aMCI is related to both sleep disturbances and circadian rhythm dysregulation, highlighting their role in cholesterol metabolism and neurodegeneration. Full article
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27 pages, 2361 KiB  
Review
Review of Thrust Regulation and System Control Methods of Variable-Thrust Liquid Rocket Engines in Space Drones
by Meng Sun, Xiangzhou Long, Bowen Xu, Haixia Ding, Xianyu Wu, Weiqi Yang, Wei Zhao and Shuangxi Liu
Actuators 2025, 14(8), 385; https://doi.org/10.3390/act14080385 - 4 Aug 2025
Viewed by 36
Abstract
Variable-thrust liquid rocket engines are essential for precision landing in deep-space exploration, reusable launch vehicle recovery, high-accuracy orbital maneuvers, and emergency obstacle evasions of space drones. However, with the increasingly complex space missions, challenges remain with the development of different technical schemes. In [...] Read more.
Variable-thrust liquid rocket engines are essential for precision landing in deep-space exploration, reusable launch vehicle recovery, high-accuracy orbital maneuvers, and emergency obstacle evasions of space drones. However, with the increasingly complex space missions, challenges remain with the development of different technical schemes. In view of these issues, this paper systematically reviews the technology’s evolution through mechanical throttling, electromechanical precision regulation, and commercial space-driven deep throttling. Then, the development of key variable thrust technologies for liquid rocket engines is summarized from the perspective of thrust regulation and control strategy. For instance, thrust regulation requires synergistic flow control devices and adjustable pintle injectors to dynamically match flow rates with injection pressure drops, ensuring combustion stability across wide thrust ranges—particularly under extreme conditions during space drones’ high-maneuver orbital adjustments—though pintle injector optimization for such scenarios remains challenging. System control must address strong multivariable coupling, response delays, and high-disturbance environments, as well as bottlenecks in sensor reliability and nonlinear modeling. Furthermore, prospects are made in response to the research progress, and breakthroughs are required in cryogenic wide-range flow regulation for liquid oxygen-methane propellants, combustion stability during deep throttling, and AI-based intelligent control to support space drones’ autonomous orbital transfer, rapid reusability, and on-demand trajectory correction in complex deep-space missions. Full article
(This article belongs to the Section Aerospace Actuators)
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15 pages, 967 KiB  
Article
Biomarker Correlations in PTSD: IL-18, IRE1, pERK, and ATF6 via Courtauld Emotional Control Scale (CECS)
by Izabela Woźny-Rasała and Ewa Alicja Ogłodek
Int. J. Mol. Sci. 2025, 26(15), 7506; https://doi.org/10.3390/ijms26157506 - 3 Aug 2025
Viewed by 176
Abstract
Post-traumatic stress disorder (PTSD) is a chronic mental health condition resulting from exposure to traumatic events. It is associated with long-term neurobiological changes and disturbances in emotional regulation. Understanding the sociodemographic profiles, biomarkers, and emotional control in patients with PTSD helps to better [...] Read more.
Post-traumatic stress disorder (PTSD) is a chronic mental health condition resulting from exposure to traumatic events. It is associated with long-term neurobiological changes and disturbances in emotional regulation. Understanding the sociodemographic profiles, biomarkers, and emotional control in patients with PTSD helps to better comprehend the impact of the disorder on the body and its clinical course. An analysis of biomarkers such as Interleukin-18 (IL-18), Inositol-Requiring Enzyme 1 (IRE1), Phosphorylated Extracellular Signal-Regulated Kinase (pERK), and Activating Transcription Factor–6 (ATF-6) in PTSD patients with varying durations of illness (≤5 years and >5 years) and a control group without PTSD revealed significant differences. Patients with recently diagnosed PTSD (≤5 years) showed markedly elevated levels of inflammatory and cellular stress markers, indicating an intense neuroinflammatory response during the acute phase of the disorder. In the chronic PTSD group (>5 years), the levels of these biomarkers were lower than in the recently diagnosed group, but still significantly higher than in the control group. An opposite trend was observed regarding the suppression of negative emotions, as measured by the Courtauld Emotional Control Scale (CECS): individuals with chronic PTSD exhibited a significantly greater suppression of anger, depression, and anxiety than those with recent PTSD or healthy controls. Correlations between biomarkers were strongest in individuals with chronic PTSD, suggesting a persistent neuroinflammatory dysfunction. However, the relationships between biomarkers and emotional suppression varied depending on the stage of PTSD. These findings highlight the critical role of PTSD duration in shaping the neurobiological and emotional mechanisms of the disorder, which may have important implications for therapeutic strategies and patient monitoring. Full article
(This article belongs to the Section Molecular Genetics and Genomics)
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17 pages, 4689 KiB  
Article
Oscillation Mechanism of SRF-PLL in Wind Power Systems Under Voltage Sags and Improper Control Parameters
by Guoqing Wang, Zhiyong Dai, Qitao Sun, Shuaishuai Lv, Nana Lu and Jinke Ma
Electronics 2025, 14(15), 3100; https://doi.org/10.3390/electronics14153100 - 3 Aug 2025
Viewed by 135
Abstract
The synchronous reference frame phase-locked loop (SRF-PLL) is widely employed for grid synchronization in wind farms. However, it may exhibit oscillations under voltage sags or improper parameter settings. These oscillations may compromise the secure integration of large-scale wind power. Therefore, mitigating the oscillations [...] Read more.
The synchronous reference frame phase-locked loop (SRF-PLL) is widely employed for grid synchronization in wind farms. However, it may exhibit oscillations under voltage sags or improper parameter settings. These oscillations may compromise the secure integration of large-scale wind power. Therefore, mitigating the oscillations of the SRF-PLL is crucial for ensuring stable and reliable operation. To this end, this paper investigates the underlying oscillation mechanism of the SRF-PLL from local and global perspectives. By taking into account the grid voltage and control parameters, it is revealed that oscillations of the SRF-PLL can be triggered by grid voltage sags and/or the improper control parameters. More specifically, from the local perspective, the SRF-PLL exhibits distinct qualitative behaviors around its stable equilibrium points under different grid voltage amplitudes. As a result, when grid voltage sags occur, the SRF-PLL may exhibit multiple oscillation modes and experience a prolonged transient response. Furthermore, from the global viewpoint, the large-signal analysis reveals that the SRF-PLL has infinitely many asymmetrical convergence regions. However, the sizes of these asymmetrical convergence regions shrink significantly under low grid voltage amplitude and/or small control parameters. In this case, even if the parameters in the small-signal model of the SRF-PLL are well-designed, a small disturbance can shift the operating point into other regions, resulting in undesirable oscillations and a sluggish dynamic response. The validity of the theoretical analysis is further supported by experimental verification. Full article
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