Search Results (102)

Background: Cannabidiol (CBD) has demonstrated potential as a therapeutic agent for muscle tension, pain, and sleep bruxism, yet its broader impact on comorbid conditions such as sleep disturbance and migraine disability remains underexplored. This study aimed to assess the effects of topical CBD on sleep quality and migraine-related disability in patients with bruxism-associated muscular pain. Methods: In a randomized, double-blind clinical trial, 60 participants with bruxism were allocated equally into three groups: control (placebo gel), 5% CBD gel, and 10% CBD gel. Participants applied the gel intraorally to the masseter muscles nightly for 30 days. Sleep quality and migraine-related disability were assessed using the Pittsburgh Sleep Quality Index (PSQI) and the Migraine Disability Assessment Scale (MIDAS), respectively. Surface electromyography (sEMG) and the Bruxoff^® device were used for objective evaluation of muscle tension and bruxism intensity. Results: Both CBD treatment groups demonstrated statistically significant improvements in PSQI and MIDAS scores compared to the control group (p < 0.001). No significant differences were observed between the 5% and 10% CBD groups, suggesting comparable efficacy. The sEMG findings corroborated a reduction in muscle tension. Improvements in sleep and migraine outcomes were positively correlated with reductions in muscle activity and pain. Conclusions: Topical CBD gel significantly improved sleep quality and reduced migraine-related disability in patients with bruxism-associated muscular pain, supporting its role as a multifaceted therapeutic option in the management of TMD and related comorbidities. Further research is needed to confirm long-term benefits and determine optimal dosing strategies. Full article

The ultimate goal of research on seismic mitigation technologies is engineering application. However, current studies primarily focus on the application of dampers in planar structures, while actual engineering structures are three-dimensional (3D) in nature. A type of damper, making up tuned mass dampers (TMDs) and inerters, has excellent vibration mitigation performance and needs brackets to connect to structures. In this work, a coupled dynamic model of an energy dissipation system (EDS) comprising a TMD, an inerter, a bracket, and a 3D building structure is presented, along with analytical solutions for stochastic seismic responses. The main work is as follows. Firstly, based on D’Alembert’s dynamics principle, the seismic dynamic equations of an EDS considering a realistic damper and a 3D structure are formulated. The general dynamic equations governing the bidirectional horizontal motion of the EDS are further derived using the dynamic finite element technique. Secondly, analytical expressions for spectral moments and variances of seismic responses are obtained. Finally, four numerical examples are presented to investigate the following: (1) verification of the proposed response solutions, showing that the calculation time of the proposed method is approximately 1/500 of that of the traditional method; (2) examination of spatial effects in 3D structures under unidirectional excitation, revealing that structural seismic responses in the direction along the earthquake ground motion is approximately 10⁴ times that in the direction perpendicular to the ground motion; (3) investigation of the spatial dynamic characteristics of a 3D structure subjected to unidirectional seismic excitation, showing that the bracket parameters significantly affect the damping effects on an EDS; and (4) application of the optimization method for the damper’s parameters that considers system dynamic reliability and different weights of the damper’s parameters as constraints, indicating that the most economical damping parameters can achieve a reduction in displacement spectral moments by 30–50%. The proposed response solutions and parameter optimization technique provide an effective approach for evaluating stochastic seismic responses and optimizing damper parameters in large-scale and complex structures. Full article

Background: The occlusal angle (OA), influenced by pillow height, may affect muscle tension in the head and neck. However, its optimal range for minimizing muscle activation has not been clearly defined. Objective: This study aimed to investigate the effects of OA on the resting muscle activity of masticatory and cervical muscles and to identify an optimal OA range using cluster analysis and linear mixed-effects modeling. Methods: The resting muscle activities of the masseter (MAS), temporalis (TEM), sternocleidomastoid (SCM), and posterior vertebral muscles (PVM) were measured at OA conditions modulated by pillow heights of 0, 5, and 10 cm at 0, 1, and 5 min in the supine position. Intraclass correlation coefficients (ICCs) assessed measurement reliability. Statistical analyses included ANOVA, ROC curve analysis, k-means clustering, and linear mixed-effects models. Results: MAS and TEM resting muscle activity ratio (RMR) significantly increased with larger OA values (p < 0.001), while SCM showed decreased activation (p = 0.001). An OA range of 105°–111° was identified as the center of a low-activity cluster, and an upper cut-off of 138° was associated with potential muscular overload. ICC values for MAS and SCM ranged from 0.82 to 0.89, indicating excellent test–retest reliability. Conclusions: OA modulated by pillow height is a modifiable factor that influences muscle activity. An OA of 105°–111° may serve as a practical comfort zone, especially for individuals at risk of TMDs. Full article

There have been some studies investigating the effects of air pollutants on male football players, but few have examined the gender-specific impact of air pollution on the athletic performance of female football players. This research gap limits the development of tailored training and competition strategies. Here, generalized mixed modeling was employed to assess the effects of main ambient air pollutants, i.e., particulate matter less than 2.5 μm (PM_2.5), ozone (O₃), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), and carbon monoxide (CO), on athletic performance indicators (total movement distance (TMD), jogging distance (JD), and walking distance (WD)) among 14 female football players during 16 matches in the 2020 season of the Chinese Football Association Women’s Super League. Our findings indicate a significant negative association between the O₃ concentration and athletic performance, with fixed effect coefficients of −22.426 ± 8.889 for TMD, −10.817 ± 3.697 for JD, and −6.943 ± 3.265 for WD. The NO₂ concentration was significantly correlated with both TMD and JD, while PM_2.5, SO₂, and CO concentrations had minimal or negligible effects. Additionally, aerobic fitness was reduced as the O₃ concentration increased. These results provide valuable insights for optimizing gender-specific training and competition strategies under varying air quality conditions, offering a basis for more targeted health and performance interventions in professional female football players. Full article

Layered transition metal dichalcogenides (TMDs) have gained considerable attention as promising cathodes for aqueous zinc-ion batteries (AZIBs) because of their tunable interlayer architecture and rich active sites for Zn²⁺ storage. However, unmodified TMDs face significant challenges, including limited redox activity, sluggish kinetics, and insufficient structural stability during cycling. These limitations are primarily attributed to their narrow interlayer spacing, strong electrostatic interactions, the large ionic hydration radius, and their high binding energy of Zn²⁺ ions. To address these restrictions, an in situ organic polyaniline (PANI) intercalation strategy is proposed to construct molybdenum disulfide (MoS₂)-based cathodes with extended layer spacing, thereby improving the zinc storage capabilities. The intercalation of PANI effectively enhances interplanar spacing of MoS₂ from 0.63 nm to 0.98 nm, significantly facilitating rapid Zn²⁺ diffusion. Additionally, the π-conjugated electron structure introduced by PANI effectively shields the electrostatic interaction between Zn²⁺ ions and the MoS₂ host, thereby promoting Zn²⁺ diffusion kinetics. Furthermore, PANI also serves as a structural stabilizer, maintaining the integrity of the MoS₂ layers during Zn-ion insertion/extraction processes. Furthermore, the conductive conjugated PANI boosts the ionic and electronic conductivity of the electrodes. As expected, the PANI–MoS₂ electrodes exhibit exceptional electrochemical performance, delivering a high specific capacity of 150.1 mA h g⁻¹ at 0.1 A g⁻¹ and retaining 113.3 mA h g⁻¹ at 1 A g⁻¹, with high capacity retention of 81.2% after 500 cycles. Ex situ characterization techniques confirm the efficient and reversible intercalation/deintercalation of Zn²⁺ ions within the PANI–MoS₂ layers. This work supplies a rational interlayer engineering strategy to optimize the electrochemical performance of MoS₂-based electrodes. By addressing the structural and kinetic limitations of TMDs, this approach offers new insights into the development of high-performance AZIBs for energy storage applications. Full article

Transition metal dichalcogenide (TMD) materials have demonstrated promising potential for applications in photodetection due to their tunable bandgaps, high carrier mobility, and strong light absorption capabilities. However, limited by their intrinsic bandgaps, TMDs are unable to efficiently absorb photons with energies below the bandgap, resulting in a significant attenuation of photoresponse in spectral regions beyond the bandgap. This inherently restricts their broadband photodetection performance. By introducing metasurface structures consisting of subwavelength optical elements, localized plasmon resonance effects can be exploited to overcome this absorption limitation, significantly enhancing the light absorption of TMD films. Additionally, the heterogeneous integration process between the metasurface and two-dimensional materials offers low-temperature compatibility advantages, effectively avoiding the limitations imposed by high-temperature doping processes in traditional semiconductor devices. Here, we systematically investigate metasurface-enhanced two-dimensional MoSe₂ photodetectors, demonstrating broadband responsivity extension into the mid-infrared spectrum via precise control of metasurface structural dimensions. The optimized device possesses a wide spectrum response ranging from 808 nm to 10 μm, and the responsivity (R) and specific detection rate (D*) under 4 μm illumination achieve 7.1 mA/W and 1.12 × 10⁸ Jones, respectively. Distinct metasurface configurations exhibit varying impacts on optical absorption characteristics and detection spectral ranges, providing experimental foundations for optimizing high-performance photodetectors. This work establishes a practical pathway for developing broadband optoelectronic devices through nanophotonic structure engineering. Full article

The optimum tuning of the natural frequency and damping ratio of TMDs for structural modal parameters and various optimization criteria are well-known from the literature. However, when the eigenfrequency and modal mass of the target structural mode are uncertain due to estimation and measurement errors, significant life loads, temperature, and other time-varying effects, the existing TMD tuning rules are not necessarily optimal. An often-adopted method is to select the TMD damping ratio that is greater than optimal value to make the TMD less sensitive to variations of the target eigenfrequency and uncertainty in the modal mass. This heuristic approach is quantitatively investigated by the presented research. Computations are made for different TMD mass ratios, different uncertainties in target eigenfrequency and modal mass, different levels of increased TMD damping, and assuming harmonic excitation. The results demonstrate that there is no simple rule when increased TMD damping is advantageous. Therefore, beneficial TMD increase factors are given as functions of TMD mass ratio and deviations between actual and nominal modal structural properties. These data can be used by engineers for real TMD projects with uncertain modal parameters. Full article

In the current work, two novel tandem-based tuned mass damper configurations are introduced. These configurations extend the recently proposed tuned tandem mass damper inerter (TTMDI) by replacing the linking dashpot with an inerter (i.e., the inerter-connected TTMDI (ICTTMDI)), and an integrated tuned tandem mass damper inerter (I-TTMDI) by integrating recently proposed tuned tandem mass damper (TTMD) configurations. The control efficiency of the optimally designed dampers for a single-degree-of-freedom (SDOF) system was evaluated in a uniform framework to reveal and compare the performances of the ICTTMDI and I-TTMDI with those of other recently proposed tandem-based configurations. The optimum design of all the studied configurations was determined by the particle swarm optimization (PSO) algorithm. The evaluation of the performances included the effectiveness in the frequency domain and that of the norm and maximum reduction in the displacement and absolute acceleration in the time domain under 21 earthquake records with different characteristics. Additionally, the strokes of the dampers, the structure energies, and the power spectral densities (PSDs) of the responses were investigated. The optimum design of the I-TTMDI revealed the best configuration by determining the optimum distributions of the mass and inertance between the tandem mass and inerter links, respectively. The proposed configuration not only demonstrated improved response reduction across the displacement and acceleration measures but also maintained remarkable robustness under 21 earthquake records (far-fault, near-fault forward-directivity, and fling-step records). Furthermore, the advantages of the side inerter distribution were particularly effective at widening the operating frequency band, breaking through the traditional limitations of TMD-based devices. The consistent performances of the newly proposed configurations prove that they can be used to advance the development of more reliable structural control systems. Full article

Background: The purpose of this study was to investigate the effect of occlusal splints on temporomandibular disorders (TMDs) and well-being in patients with fibromyalgia and bruxism. This experimental study assessed the impact of Michigan-type occlusal splints on TMDs and well-being in fibromyalgia and bruxism patients and healthy individuals. Methods: This quasi-experimental study assesses the impact of an intervention on TMD symptoms and overall well-being in patients with fibromyalgia and bruxism. A total of 266 participants were divided into three groups: bruxism with fibromyalgia (ABFG, n = 37), sleep bruxism with fibromyalgia (SBFG, n = 53), awake bruxism without fibromyalgia (ABG, n = 45), sleep bruxism without fibromyalgia (SBG, n = 85), and a healthy control group (HG, n = 46). All participants received a rigid acrylic occlusal splint and counseling on behavioral changes. Pre- and post-treatment questionnaires measured various variables, including jaw function (JFLS-8), anxiety (GAD-7), oral health impact (OHIP-14), well-being (WHO-5), sleep quality (PSQI), and symptoms such as bruxism, TMJ pain, headaches, and jaw locking. Results: The study demonstrated that occlusal splints significantly improved various outcomes in patients with bruxism and fibromyalgia. For the ABFB, significant reductions were observed in JFLS-8, GAD-7, OHIP-14, and PSQI and increases in WHO-5 scores (p < 0.001). Similar improvements were noted in the SBFB. The ABG group showed significant changes in JFLS-8, OHIP-14, and WHO-5, but not in GAD-7 or PSQI. Furthermore, SBG exhibited significant improvements across all measures except WHO-5. Patients in the HG showed only slight changes in PSQI. Additionally, significant reductions in the prevalence of TMJ pain, headaches attributed to TMJ, and jaw locking were noted across the bruxism groups. Conclusion: This study finds that occlusal splints significantly enhance symptoms of TMD and enhance overall well-being, especially in patients with fibromyalgia. Significant improvements were observed in JFLS-8, GAD-7, OHIP-14, PSQI, and WHO-5 scores, alongside a marked reduction in the prevalence of TMJ pain, TMJ-related headaches, and jaw locking. This highlights occlusal splints as an effective therapeutic option for managing both physical and psychological symptoms in fibromyalgia patients. However, the benefits for healthy individuals were minimal, suggesting a need for further research on long-term effects and treatment optimization. Full article

Current methods for designing three-dimensional trajectories rarely account for complex formation constraints, focusing primarily on geometric relationships. However, trajectory adjustments are often necessary during drilling operations. These field adjustments typically lack systematic optimization, resulting in suboptimal trajectories. This study introduces a novel trajectory optimization framework that integrates formation fitness for curve construction and proactive anti-collision trajectory adjustment (PACTA). The framework begins by incorporating PACTA and optimizing the initial trajectory to minimize total measured depth (TMD) using a genetic algorithm. Subsequently, a second optimization phase identifies curve sections passing through formations with low build-up fitness, automatically splitting them into combinations of curves and straight lines. Dynamic trajectory equations are then constructed based on these adjustments, and the final trajectory is optimized accordingly. Case studies demonstrate that the proposed method effectively adjusts curve positions in the presence of multiple formations with low build-up fitness while avoiding wellbore collisions. The approach achieves an average 10% reduction in total drilling time when minimizing TMD and an average 19.7% reduction in drillstring torque when torque minimization is prioritized. This new trajectory design method is expected to significantly reduce well construction costs. Full article

Background: Temporomandibular disorders (TMDs) are a group of conditions affecting the temporomandibular joint (TMJ) and associated muscles, leading to pain, restricted jaw movement, and impaired quality of life. Conventional treatments, including physical therapy, medications, and surgical interventions, have varying degrees of success and potential side effects. Cannabidiol (CBD), a non-psychoactive component of cannabis, has gained attention for its anti-inflammatory, analgesic, and anxiolytic properties. This study explores the potential role of CBD in TMD management. Methods: A review of existing literature was conducted (2007–2024), focusing on preclinical and clinical studies assessing the efficacy of CBD in pain modulation, inflammation reduction, and muscle relaxation. Relevant studies were sourced from PubMed, Scopus, and Web of Science databases. Additionally, potential mechanisms of action, including interactions with the endocannabinoid system, were analyzed. Results: Studies suggest that CBD exerts analgesic and anti-inflammatory effects by modulating CB1 and CB2 receptors, reducing cytokine release, and influencing neurotransmitter pathways. Preliminary clinical evidence indicates that CBD may alleviate TMD-related pain and muscle tension with minimal adverse effects. However, high-quality randomized controlled trials are limited. Conclusions: CBD demonstrates promise as a potential adjunctive treatment for TMD. Further research, including well-designed clinical trials, is necessary to establish its efficacy, optimal dosage, and long-term safety. Full article

The rapid expansion of global infrastructure has amplified the environmental impact of construction, particularly through the carbon footprint of structures. Addressing this challenge, this study examined the potential of vibration control systems to reduce the carbon footprint of steel-frame buildings subject to dynamic wind loads. Utilizing the Force Analogy Method (FAM), which effectively addresses nonlinearity in structural analysis, the research modeled a 10-story steel frame subjected to synthetic downburst wind time history velocities generated through spectral simulation techniques. Both passive and active control systems were implemented, with a focus on tuned mass dampers (TMDs) and active mass dampers (AMDs) to reduce structural displacements and accelerations. The results revealed that these systems not only significantly reduce the peak structural responses but also, when combined with optimized manufacturing methods, lead to a decrease in steel usage. This optimization contributes to a reduction of up to 20% in CO₂ emissions during the pre-use stage of a building’s lifecycle. By enhancing the material efficiency and minimizing the environmental impacts, this research highlights the critical role of advanced control systems, supported by new nonlinear analytical methods, in promoting environmentally conscious engineering. This approach aims to guide future generations in developing structural engineering projects that prioritize sustainable practices. Full article

To reduce earthquake damage and its effect on the structures, tuned mass dampers (TMDs) are generally positioned on the top of the structures for effectiveness, but existing TMDs on the story levels have problems due to space and additional vertical load issues. Underground-tuned mass dampers (UTMDs) can be used for base-isolated structures to limit deformations of base isolation systems. This study aims to determine the optimum design parameters of an underground tuned mass damper (UTMD) combined with based isolated systems. The best-performing algorithm among the metaheuristic algorithms selected for the optimal design of the UTMD system was investigated. Classical and hybrid forms of several metaheuristic algorithms were used in the methodology. The hybrid of the Jaya algorithm and Teaching Learning-Based Optimization was found to be the most effective one for the reduction of maximum accelerations. The cases limiting the damping of the base-isolation system and various mass ratios of UTMD were also conducted. In conclusion, the control system can reduce the maximum acceleration of the optimum base-isolated structure by 4% to 23% according to the mass ratio of UTMD and provide a low-damping isolation design as the optimum one. Full article

The temporomandibular joint (TMJ) is essential for chewing and speaking functions, as well as for making facial expressions. However, this joint can be affected by disorders, known as temporomandibular disorders (TMDs), induced by complex causes that lead to limitations in daily activities. Building on the methodology and findings from our previous study on TMJ function, our research aims to apply the established criteria and norms to patients with TMDs. The primary goal is to evaluate the applicability and clinical relevance of these reference norms in predicting the severity and progression of TMJ disorders within a clinical population. Using non-invasive myotonic measurements, we evaluated 157 subjects, including both non-TMD-affected and TMD-affected individuals. To achieve optimal results, five primary parameters (frequency, stiffness, decrement, relaxation time, and creep) were analyzed using statistical–physical tools, providing quantitative functionality degrees across different previously examined clinical groups. The obtained results identified significant quantitative markers for early diagnosis and personalized treatment of TMJ disorders. This interdisciplinary approach leads to a deeper understanding of TMJ dysfunctions and makes a meaningful contribution to clinical practice, providing more precise tools for managing and treating this complex condition. Full article

Among all the existing possibilities within the renewable energies field, wind energy stands out due to the significant expansion of offshore turbines installed in coastal and deep-sea areas. Although the latter represent considerable energy generation potential due to their larger size and location in areas of strong winds, they are exposed to harsh environmental disturbances, particularly waves, causing these structures to experience vibrations, increasing in this way fatigue, reducing efficiency, and leading to higher maintenance and operational costs. In this work, vibration reduction is achieved using two structural control systems for a 5 MW barge-type floating offshore wind turbine (FOWT), tuned via a metaheuristic method, with genetic algorithms (GAs). Firstly, the standard deviation of the Top Tower Displacement (TTD) is used as a cost function in the GA to optimize a passive Tuned Mass Damper (TMD), resulting in a vibration suppression rate of 34.9% compared to a reference standard TMD. Additionally, two semi-active structural control systems based on a gain scheduling approach are proposed. In one of the approaches, the TMD parameters are optimized based on the amplitude of oscillations, achieving a suppression rate of 45.4%. In the second approach, the TMD parameters are optimized in real time for the identified wave frequencies, demonstrating superior performance for medium-high frequencies compared to the other TMDs. Full article