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Laboratory predictions for the fatigue life of an asphalt mixture under cyclic loading based on the plateau value (PV) of the permanent deformation ratio (PDR) were carried out by three-point bending fatigue tests. The influence of test conditions on the recovery ratio of elastic deformation (RRED), the permanent deformation (PD) and PDR, and the trends of RRED, PD, and PDR were studied. The damage variable was defined by using PDR, and the relation of the fatigue life to PDR was determined by analyzing the damage evolution process. The fatigue equation was established based on the PV of PDR and the fatigue life was predicted by analyzing the relation of the fatigue life to the PV. The results show that the RRED decreases with the increase of the number of loading cycles, and the elastic recovery ability of the asphalt mixture gradually decreases. The two mathematical models proposed are based on the change laws of the RRED, and the PD can well describe the change laws. The RRED or the PD cannot well predict the fatigue life because they do not change monotonously with the fatigue life, and one part of the deformation causes the damage and the other part causes the viscoelastic deformation. The fatigue life decreases with the increase of the PDR. The average PDR in the second stage is taken as the PV, and the fatigue life decreases in a power law with the increase of the PV. The average relative error of the fatigue life predicted by the fatigue equation to the test fatigue life is 5.77%. The fatigue equation based on PV can well predict the fatigue life.
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http://dx.doi.org/10.3390/ma11050722 | DOI Listing |
Acta Neurol Belg
September 2025
Neuroscience Research Australia, University of New South Wales, Sydney, Australia.
Objectives: Patients diagnosed with amyotrophic lateral sclerosis (ALS) typically describe symptoms of fatigue. Despite this frequency, the underlying mechanisms of fatigue are poorly understood, and are likely multifactorial. To help clarify mechanisms, the present systematic review was undertaken to determine the risk factors related to fatigue in ALS.
View Article and Find Full Text PDFEur J Anaesthesiol
September 2025
From the Department of Anaesthesiology, Intensive Care Medicine, Emergency Medicine and Multidisciplinary Pain Centre, Ziekenhuis Oost-Limburg, Genk (WR, DM, IM, HS, ST), Department of Anaesthesiology, University Hospitals Leuven (WR, SR), Department of Cardiovascular Sciences, KU Leuven, Leuven (WR
Postoperative fatigue (POF) and perioperatively acquired muscle weakness (POAW) are significant yet often under-recognised interlinked postoperative complications that can significantly hinder postoperative recovery and diminish overall quality of life after surgery. Despite advancements in surgical and anaesthetic techniques and the widespread implementation of Enhanced Recovery After Surgery (ERAS) protocols, these conditions remain prevalent. In the weeks following surgery, reported incidences of fatigue of any severity range from 10% to as high as 90%, depending on the patient population.
View Article and Find Full Text PDFMedicine (Baltimore)
September 2025
Institute for Medical Education, University of Bern, Bern, Switzerland.
Long COVID, or post-COVID-19 condition, is characterized by symptoms persisting beyond 12 weeks after severe acute respiratory syndrome coronavirus 2 infection, affecting individuals regardless of acute disease severity. Fatigue - often linked with depression and anxiety - is among its most debilitating manifestations. However, the associations between fatigue subtypes (physical vs mental), mental health symptoms, and acute disease severity on long-term health-related quality of life (HRQoL) remain unclear.
View Article and Find Full Text PDFBMJ Open Qual
September 2025
Jordan University, Amman, Jordan.
Objectives: To assess the efficacy of motivational messages on nurses' professional quality of life and well-being.
Design: The present systematic review was conducted according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses, a widely accepted framework for conducting systematic reviews. The researchers used specific keywords to search for eligible studies in several databases.
J Biomech
August 2025
Lampe Joint Department of Biomedical Engineering, UNC Chapel Hill & NC State University, Chapel Hill, NC, USA. Electronic address:
Walking is essential for maintaining independence and quality of life, yet aging may impair the neuromuscular function required for stable gait over time. This study sought to quantify age-related differences in step-to-step control during prolonged walking using detrended fluctuation analysis (DFA). We hypothesized that step-to-step changes in step length and step width would exhibit reduced temporal persistence over time, with more pronounced effects in older than in younger adults.
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