Search Results (1,589)

The bottleneck of service stability of perovskite solar cells is rooted in the mechanical failure of its active layer materials at the micro scale. In order to deeply understand this process, the nano-indentation mechanical response of all-inorganic perovskite CsPbBr₃ under pre-stress was studied by molecular dynamics simulation at the atomic scale. The core of this research work is to systematically reveal the quantitative influence of prestress, an inevitable initial stress state in the preparation and service of practical devices, on the near-surface mechanical behavior of materials. Firstly, the stress–strain response of the CsPbBr₃ model at 300 K, 350 K, and 400 K was verified. The temperature dependence of its mechanical properties and the consistency with the experimental values confirmed the reliability of the force field and simulation method. In addition, by applying a series of uniaxial pre-strains, we analyzed the influence of prestress on the evolution of the force-depth curve and indentation strain during nano-indentation. The results show that the introduction of pre-strain will induce the material to have a significant “softening effect” and systematically reduce its ability to resist the intrusion of the indenter. More importantly, this study quantitatively reveals the asymmetric influence of prestress direction: tensile prestress leads to more serious softening than compressive prestress with the same amplitude, indicating that materials are more prone to plastic deformation under tensile preload. This work clarifies the key regulation function of prestress on the mechanical properties of perovskite thin films and provides a crucial theoretical basis for constructing accurate cross-scale mechanical models and designing perovskite photoelectric devices with high reliability and fatigue resistance. Full article

(1) Background: Exoskeleton systems are being used increasingly in medical rehabilitation and industrial assistance. Accurate evaluation of their performance is crucial for optimising design and improving performance. In this paper, we propose a performance evaluation index system for exoskeletons and a quantitative evaluation method based on multi-source signal fusion. (2) Methods: The system utilises a variety of sensors for signal collection, encompassing sEMG and MMG, which are indicative of muscular fatigue, along with IMU signals, which demonstrate the movement of both the exoskeleton and the human body. This is then combined with the subjective evaluation scale to constitute the exoskeleton effectiveness assessment index system. (3) Results: This study evaluates two types of material handling exoskeletons. The findings indicate that the ultimate scores for the single-hip and hip-knee exoskeletons are 0.625 and 0.845, respectively. (4) Conclusions: A comparison of the indexes of the two exoskeletons and the subjective evaluations of the testers reveals that this method effectively quantifies the exoskeleton’s human metabolism, human–machine synergy and performance in working conditions, as well as the perceived effectiveness of assistance in different working conditions. Full article

Large-scale wind farms operate under highly unsteady atmospheric inflows, where transient turbulence, dynamic wake interactions, and inflow-wake coupling reduce energy production and exacerbate turbine loads. Over the past five years, advances in high-fidelity computational fluid dynamics (CFDs), large eddy simulation (LES), machine learning (ML)-based wake modeling, and multi-objective optimization have reshaped wind farm layout optimization under dynamic inflow conditions. This review synthesizes recent progress in five key areas: dynamic inflow and high-fidelity wake modeling (including LES-driven transient wake evolution and turbulence-resolved inflow generation), data-driven wake prediction, multi-objective layout optimization (considering the annual energy production (AEP), fatigue load constraints, and the levelized cost of energy (LCOE)), blockage modeling for complex terrain and yaw misalignment, and real-time optimization addressing inflow, turbine performance, and modeling uncertainties. Coupling transient wake models with surrogate-assisted multi-objective optimization enables a computationally efficient and physically consistent layout design. Key open challenges (dynamic wake controllability, real-time optimization under uncertainty, and integration with next-generation farm-level control systems) and future directions for enhancing large-scale wind farm resilience and cost-competitiveness are also identified. However, despite significant progress, existing models still face fundamental limitations, such as oversimplified treatment of complex turbulence structures, poor generalization under extreme or atypical conditions, and inadequate capture of long-timescale dynamic responses, which constrain their reliability in practical optimization settings. Full article

Lignin, an abundant and renewable biopolymer, holds significant potential for asphalt modification owing to its unique aromatic structure and reactive functional groups. This review summarizes the main lignin preparation routes and key physicochemical attributes and assesses its applicability for enhancing asphalt performance. The physical incorporation of lignin strengthens the asphalt matrix, improving its viscoelastic properties and resistance to oxidative degradation. These enhancements are mainly attributed to the cross-linking effect of lignin’s polymer chains and the antioxidant capacity of its phenolic hydroxyl groups, which act as free-radical scavengers. At the mixture level, lignin-modified asphalt (LMA) exhibits improved aggregate bonding, leading to enhanced dynamic stability, fatigue resistance, and moisture resilience. Nevertheless, excessive lignin content can have a negative impact on low-temperature ductility and fatigue resistance at intermediate temperatures. This necessitates careful dosage optimization or composite modification with softeners or flexible fibers. Mechanistically, lignin disperses within the asphalt, where its polar groups adsorb onto lighter components to boost high-temperature performance, while its strong interaction with asphaltenes alleviates water-induced damage. Furthermore, life cycle assessment (LCA) studies indicate that lignin integration can substantially reduce or even offset greenhouse gas emissions through bio-based carbon storage. However, the magnitude of the benefit is highly sensitive to lignin production routes, allocation rules, and recycling scenarios. Although the laboratory research results are encouraging, there is a lack of large-scale road tests on LMA. There is also a lack of systematic research on the specific mechanism of how it interacts with asphalt components and changes the asphalt structure at the molecular level. In the future, long-term service-road engineering tests can be designed and implemented to verify the comprehensive performance of LMA under different climates and traffic grades. By using molecular dynamics simulation technology, a complex molecular model containing the four major components of asphalt and lignin can be constructed to study their interaction mechanism at the microscopic level. Full article

Background/Objectives: Fibromyalgia syndrome (FMS) is a chronic condition characterized by widespread pain, fatigue, sleep disturbances, and psychological symptoms. Aquatic exercise offers the benefits of physical activity with reduced mechanical stress. This meta-analysis evaluated the effectiveness of AE on pain, functional physical status, and health-related quality of life. Methods: A PRISMA-guided systematic review and meta-analysis (PROSPERO CRD42025115158) included randomized and non-randomized trials up to October 2025 from MEDLINE (PubMed), Cochrane Library, PEDro, CINAHL Complete, SPORTDiscus, and Academic Search Ultimate. Eligible participants were adults diagnosed with FMS undergoing AE programs, alone or combined with other modalities. Standardized mean differences (SMD) with 95% confidence intervals were pooled using random- or fixed-effects models. Methodological quality, risk of bias, and certainty of evidence were evaluated using the PEDro scale, the RoB 2.0 tool, and the GRADE approach. Results: 27 trials (n = 1785; >95% women; mean age 44–62 years) were included. AE significantly improved pain (SMD = −0.92; 95% CI: −1.03 to −0.80; p < 0.00001), physical function (SMD = −0.74; 95% CI: −0.84 to −0.63; p < 0.00001), and HRQoL (SMD = 0.57; 95% CI: 0.42 to 0.72; p < 0.00001). Effects were consistent across time frames, though overall heterogeneity was considerable (Tau² = 4.93; I² = 97%). The mean PEDro score was 5.2/10, and RoB 2.0 indicated moderate methodological limitations mainly due to a lack of blinding. Evidence certainty was low for the main outcomes and moderate for adverse events. Conclusions: Aquatic exercise is an effective and safe complementary therapy for patients with FMS, alleviating pain while enhancing function and quality of life. However, methodological variability and small sample sizes warrant further high-quality trials to confirm these findings and explore underlying mechanisms. Full article

Under random wave loading, the crack growth rate exhibits jump-like cycle-to-cycle variations, which limit the direct use of efficient integration schemes such as the Euler method. In addition, the crack growth life is highly sensitive to the initial crack size and aspect ratio, while the initial defects are often difficult to determine accurately in practice, leading to increased uncertainty in life assessment. To address these issues, a cycle-scaling-based crack size accumulation method for random loading is proposed. A predictor–corrector improved Euler method is then established, and a fourth-order Runge–Kutta scheme incorporating the cycle-scaling transformation is derived. Furthermore, based on spectral analysis theory, a mapping between the wave spectrum and the crack-tip stress intensity factor response spectrum is developed. A stress intensity factor range sequence is generated by concatenating short-term sea states, thereby providing a random loading input that preserves the required statistical characteristics. Finally, a 21,000-TEU container ship is analyzed as a case study to investigate crack growth evolution for different initial aspect ratios. The results show that the crack aspect ratio gradually converges to a particular trend during propagation. A convergent aspect ratio curve is fitted. And a unified life assessment curve is constructed. An equivalent transformation is used to map an arbitrary initial crack shape and size to an equivalent convergent aspect ratio crack. As a result, fatigue life can be rapidly estimated using a single “initial crack size–fatigue life” curve, providing support for crack growth life assessment and the definition of defect acceptance limits for ship hull structures. Full article

Background/Objectives: Older adults with hearing loss frequently report increased listening effort and fatigue, particularly in complex auditory environments. These subjective experiences may reflect increased cognitive resource allocation during both auditory and visual tasks, yet the impact of hearing aids on task-related effort and fatigue remains unclear. This study examined subjective effort and fatigue in experienced older adult hearing aid users while completing cognitively demanding auditory and visual tasks in quiet and background noise, with and without hearing aids. Methods: Thirty-one adults aged 60–87 years completed a cognitive battery assessing inhibition, attention, executive function, and auditory and visual working memory across four listening conditions: aided-quiet, unaided-quiet, aided-noise, and unaided-noise. Subjective effort was measured using the NASA Task Load Index, and task-related fatigue was assessed using a situational fatigue scale. Linear mixed-effects models controlled for age and pure-tone average hearing thresholds. Results: Participants reported significantly lower effort and fatigue in quiet compared to background noise, regardless of hearing aid use. The aided-quiet condition was rated as the least effortful and fatiguing, whereas the unaided-noise condition was rated as the most demanding. Subjective effort and fatigue were moderately to strongly correlated across conditions, particularly in noise. Auditory working memory performance was significantly associated with subjective fatigue across listening conditions, while visual working memory was not associated with effort or fatigue. Hearing aid use did not produce significant reductions in effort or fatigue across conditions. Conclusions: Background noise substantially increases perceived task-related effort and fatigue during cognitively demanding auditory and visual tasks in older adults with hearing loss. While hearing aids did not significantly reduce effort or fatigue across conditions, optimal listening environments were associated with the lowest subjective reports. Auditory working memory emerged as a key factor related to fatigue, highlighting the interplay between hearing, cognition, and subjective listening experiences in older adulthood. Full article

Background: Non-motor symptoms in Parkinson’s disease (PD) consist of a wide spectrum of gastrointestinal impairment, urinary dysfunction, sleep disturbances, fatigue and psychiatric disorders. Mood disorders like anxiety and depression are linked to general well-being and overall quality of life, therefore influencing the amount and quality of restful sleep that the patients can achieve. Objectives: The aim of this study is to determine the prevalence and characteristics of anxiety and depression in PD and to identify the factors that correlate with sleep disturbances. Methods: We conducted a case–control study which included 131 PD patients and 131 controls. Descriptive data was collected, and validated scales and questionnaires regarding sleep, motor symptoms and symptoms related to anxiety and depression were administered. Patients were divided into groups by the presence or absence of sleep disorders (“bad sleepers” and “good sleepers”) and by the presence or absence of anxiety and depression. Comparative analysis was performed. Results: PD patients reported more clinically significant depression than controls and those with concomitant sleep impairment scored higher on depression- and anxiety-specific scales than their better-sleeping counterparts. Age, motor status and sleep impairment were found to be factors associated with depression in PD patients. The presence of sleep disorders was also associated with anxiety. Conclusions: Depression and anxiety are frequent in PD and are associated with comorbid sleep disturbances. Full article

Objective: To evaluate the effectiveness of a pharmacist-led educational intervention in reducing premenstrual syndrome (PMS) symptoms and improving self-care practices. Methods: A mixed-design study was conducted in community pharmacies in Spain between January and June 2025. First, a cross-sectional analysis determined PMS prevalence. Second, a longitudinal pre-post study was performed with women suffering from PMS. The intervention involved personalized guidance and an evidence-based educational infographic. Primary outcomes included symptom severity (measured by a numeric rating scale) and quality of life. Results: 350 women participated in the study. The mean age of participants was 23.7 ± 6.3 years (range: 17–51 years). At the six-month follow-up, the PMS group showed a significant reduction in mean pain intensity (from 6.86 to 3.26; p < 0.001) and a smaller reduction in the control group (from 4.82 to 2.88; p < 0.001), alongside improvements in irritability, insomnia, and fatigue. The proportion of women reporting a negative impact on quality of life decreased from 97.0% to 60.8% (p < 0.001). Oral contraceptive use was identified as a protective factor (OR: 0.33; 95% CI: 0.17–0.65). Conclusions: Educational interventions led by community pharmacists are effective in significantly alleviating PMS symptoms and enhancing women’s quality of life. Practice Implications: Community pharmacists are strategically positioned to identify women with PMS and provide evidence-based education. Implementing structured protocols and visual tools in pharmacies can optimize symptom management and promote self-care. Full article

Introduction: Myasthenia gravis (MG) is a chronic autoimmune disorder in which fatigue represents one of the most burdensome symptoms. This multidimensional manifestation extends beyond neuromuscular fatigability and has a substantial impact on daily functioning, mental health, and quality of life. The present study aimed to evaluate the perception of fatigue in patients with MG, with particular emphasis on its interference with everyday activities and the extent to which it is understood by others. Methods: The study included 67 MG patients (61.2% women, mean age 53 years) treated at the Neurology Outpatient Department of the University Clinical Center in Gdańsk. Data were collected using an author-developed survey and standardized instruments: Chalder Fatigue Scale (CFQ), MG-ADL, MG-QoL15, HADS-M, Mini-COPE, and ACDS. Results: More than 70% of patients reported constant or frequent fatigue. Higher fatigue severity was positively associated with functional impairment (MG-ADL) and lower quality of life (MG-QoL15). More than 70% of patients reported constant or frequent fatigue. Higher fatigue severity was moderately associated with greater functional impairment and poorer quality of life. The extent to which fatigue interfered with daily life was associated with higher levels of depressive symptoms, poorer self-rated health, and less favorable disease-related perceptions (acceptance and influence). In contrast, perceiving fatigue as being better understood by others was associated with lower anxiety and depression and more favorable disease-related perceptions (acceptance, control, understanding), while it was not significantly related to fatigue severity, functional status, or quality of life. Conclusions: Fatigue in myasthenia gravis is a prevalent symptom, closely related to functional impairment and reduced quality of life. Different aspects of fatigue perception show distinct psychosocial correlates, highlighting the importance of considering subjective and social dimensions of fatigue alongside its severity. These findings support the relevance of psychosocial factors in the comprehensive care of patients with MG. Full article

Background: Spondyloarthritis (SpA) typically develops before 40 years of age, but increasing life expectancy has led to a growing number of cases in older adults. It is well known that age at onset may influence disease presentation, comorbidities, and patient outcomes. Objectives: To assess whether age at onset influences SpA clinical presentation. Methods: We analyzed clinical, demographic, clinimetric, and imaging data in 272 SpA patients, grouped by onset age: early (≤40, n = 119), intermediate (41–59, n = 127), and late (≥60, n = 26). All patients had a minimum follow-up duration of 12 months. Their epidemiologic, clinic, and clinimetric data were collected, as well as patient-reported outcome measures (PROs) [Patient Global Assessment (PGA), Health Assessment Questionnaire (HAQ), FACIT-Fatigue (FACIT-F), SHORT-FORM 36 (SF-36), Hospital Anxiety and Depression Scale (HADS), Work Productivity and Activity Impairment Questionnaire (WPAI), CSI (Central Sensitization Inventory), and Psoriatic Arthritis Impact of Disease (PsAID) questionnaire]. In univariate analyses, differences in categorical variables across onset groups were assessed using Fisher’s exact test; for continuous variables, between-group comparisons were performed using the Mann–Whitney U test (two-tailed) or the Kruskal–Wallis test, as appropriate, with Bonferroni correction for post hoc analyses. Multivariable regression models were subsequently fitted, adjusting for sex, diagnosis, and disease duration. For binary outcomes, multivariable logistic regression models were used, while multivariable linear regression models (ANCOVA) were applied for continuous outcomes. The overall association between onset group and each outcome was formally tested using likelihood ratio tests, comparing models including the onset variable with nested models excluding it. A p-value < 0.05 was considered statistically significant. Results: Patients’ mean age was 60.0 ± 13.7 years; 55.9% of them were males; and there were 188 cases (69.1%) of psoriatic arthritis (PsA) and 84 cases (30.9%) of ankylosing spondylitis (AS). In early-onset patients, inflammatory back pain (IBP) was more frequent, whereas late-onset patients more often presented with joint swelling. A family history of SpA and psoriasis was less common in late-onset forms. Comorbidities, including osteoporosis, osteoarthritis, hypertension, hyperuricemia, and diabetes, were more prevalent in older-onset patients, resulting in a higher overall comorbidity burden in Groups 2 and 3. Patient-reported outcomes were largely similar across age groups, although work activity limitation was more pronounced in younger patients. Conclusions: Age at onset seems to influence SpA phenotypes: early-onset could favor axial involvement, while late-onset may associate with peripheral arthritis. Late-onset forms are associated with a more severe comorbidity burden, in particular for cardiovascular risk factors. Lung involvement proved to be more prevalent with respect to the general population, so it should be checked in the routinary assessment of SpA patients. These findings suggest that rheumatologists could tailor their routine assessments based on patients’ age at disease onset. Interestingly, work productivity seems more impacted in early-onset patients. All these points highlight the importance of age at disease onset in SpA, guiding toward personalized medicine in terms of follow-up, therapy, and more holistic patient management. Full article

Offshore wind-farm performance remains constrained by persistent wake deficits and turbulence that compound across intra-farm, intra-cluster, and inter-cluster scales, particularly under atmospheric neutral–stable stratification. A concept is advanced whereby offshore wind-farm yield may be augmented by pairing conventional horizontal-axis wind turbines (HAWTs) with lighter-than-air parafoil systems that entrain higher-momentum air and re-energise wakes, complementing yaw/induction-based wake control and enabling higher array energy density. A concise synthesis of wake physics and associated challenges motivates opportunities for active momentum re-injection, while a review of kite technologies frames design choices for lift generation and spatial keeping. Stability and control, spanning static and dynamic behaviours, tether dynamics, and response to extreme meteorological conditions, are identified as key challenges. System-integration pathways are outlined, including alignment and mounting options relative to turbine rows and prevailing shear. A staged validation programme is proposed, combining high-fidelity numerical simulation with wave-tank testing of coupled mooring–tether dynamics and wind-tunnel experiments on scaled arrays. Evaluation metrics emphasise net energy gain, fatigue loading, availability, and Levelized Cost of Energy (LCOE). The paper concludes with research directions and recommendations to guide standards and investment, and with a quantitative assessment of the techno-economic significance of kite–HAWT integration at scale. Full article

During the extrusion of novel nickel-based powder superalloy bars, the die is subjected to elevated temperatures, high pressures, and severe friction, which readily lead to abrasive wear and thermal-fatigue damage. These failures deteriorate the quality of the extruded products and significantly shorten the service life of the die. Frequent repair and replacement of the tooling ultimately increase the overall manufacturing cost. This study investigates the friction and wear behavior of H13 and 5CrNiMo hot-work tool steels under extreme transient high-temperature conditions by combining finite element simulation with tribological testing. The temperature and stress distributions of the billet and key tooling components during extrusion were analyzed using DEFORM-3D. In addition, pin-on-disk friction and wear tests were conducted at 1000 °C to examine the friction coefficient, wear morphology, and subsurface grain structural evolution under various loading conditions. The results show that the extrusion die and die holder experience the highest loads and most severe wear during the extrusion process. For 5CrNiMo tool steel, the wear mechanism under low loads is dominated by mild abrasive wear and oxidative wear, whereas increasing the load causes a transition toward adhesive wear and severe oxidative wear. In contrast, H13 tool steel exhibits a transition from abrasive wear to severe oxidative wear. In 5CrNiMo steel, friction-induced recrystallization, grain refinement, and softening lead to the formation of a mechanically mixed layer, which, together with a stable third-body layer, markedly reduces and stabilizes the friction coefficient. H13 steel, however, undergoes surface strain localization and spalling, resulting in persistent fluctuations in the friction coefficient. The toughness and adhesion of the oxide film govern the differences in wear mechanisms between the two steels. Owing to its higher Cr, V, and Mo contents, H13 forms a dense but highly brittle oxide scale dominated by Cr and Fe oxides at 1000 °C. This oxide layer readily cracks and delaminates under frictional shear and thermal cycling. The repeated spalling exposes the fresh surface to further oxidation, accompanied by recurrent adhesion–delamination cycles. Consequently, the subsurface undergoes alternating intense shear and transient load variations, leading to localized dislocation accumulation and cracking, which suppresses the progression of continuous recrystallization. Full article

Background/Objectives: In recent years, quiet quitting has attracted increasing attention in nursing research and is conceptualized as a phenomenon in which nurses perform their professional duties at a minimal level without physically leaving their jobs. This study aimed to adapt the Quiet Quitting Scale into Turkish, evaluate its psychometric properties, and examine the relationships between stress of conscience, compassion fatigue, and quiet quitting among nurses. Methods: This is a descriptive, correlational, and methodological study. This study was conducted between 20 February and March 2025 with the participation of 205 nurses working in a university hospital in Turkey. The data were collected using the Nurse Descriptive Information Form, Stress of Conscience Questionnaire, Compassion Fatigue-Short Scale, and Quiet Quitting Scale. Results: The results indicated positive associations between stress of conscience, compassion fatigue, and quiet quitting. Mediation analysis revealed that compassion fatigue had a significant indirect effect on the association between stress of conscience and quiet quitting, while the direct relationship remained significant, suggesting partial mediation. Conclusions: These findings highlight the importance of supportive work environments where nurses can address ethical concerns and access interventions aimed at preventing compassion fatigue. Organizational strategies that promote psychological well-being may help sustain nurses’ work engagement and reduce quiet quitting. Full article

Subarachnoid hemorrhage (SAH) is a devastating form of stroke that disproportionately affects younger individuals and often results in long-term disability, even among those who achieve favorable outcomes on traditional clinical scales. This scoping review uses the PRISMA-ScR protocol to evaluate independent studies from 1980 to 2025 and synthesizes current evidence on sleep and cognitive dysfunction in SAH survivors, highlighting their prevalence, impact, and gaps in assessment and management. A total of 2243 publications were screened across three databases (PubMed, EMBASE, and Web of Science), which resulted in 115 studies analyzed for review. Sleep disturbances—including insomnia, hypersomnia, and sleep apnea—are common across all phases of recovery and are closely linked to fatigue, mood disorders, and impaired cognitive function. Cognitive deficits, particularly in memory, executive function, and attention, persist in most survivors and are significant barriers to return to work and reintegration. Despite their clinical relevance, these domains are underrepresented in SAH research and inadequately captured by standard outcome measures such as the modified Rankin Scale. Compared to moderate-to-severe traumatic brain injury (TBI), the SAH literature lacks standardized assessment tools, longitudinal data, and interventional studies. Neuroinflammation may underlie both sleep and cognitive sequelae, offering a potential therapeutic target. This review underscores the need for patient-centered outcome measures, integrated sleep and cognitive assessments, and targeted interventions to improve long-term brain health in SAH survivors. Full article