This study investigated the service life prediction of fluorocarbon elastomers that are used in automotive vapor fuel hoses under thermal environments. The changes in mechanical properties such as the tensile strength, elongation, compression set (CS), and hardness according to thermal aging were investigated for two types of ternary fluoroelastomers. Destructive tests of the tensile strength and elongation showed large variations in the mechanical properties under the same condition because there is no continuity of samples. In contrast, nondestructive tests of the CS and hardness showed little variations in the mechanical properties under the same condition. The elongation, CS, and hardness were selected as the physical parameters for service life prediction as they showed a tendency according to the aging temperature, which is an accelerating factor. The effective activation energy derived using each physical parameter was 74.91-159.6 kJ mol, and the service life was 17.8-140 × 10 h based on B. In this study, hardness, which has a small deviation between samples, is considered appropriate as mechanical parameter for predicting the service lifetime.
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http://dx.doi.org/10.3390/polym14102047 | DOI Listing |
Lancet Reg Health West Pac
January 2025
Department of Medicine, National University of Singapore, Yong Loo Lin School of Medicine, Singapore, Singapore.
Background: Little is known about the practices and resources employed by general practitioners (GPs) in Singapore to manage late-life depression. As the country is stepping up its efforts to promote collaborative care across community mental health and geriatric care, understanding GPs' current practices when managing late-life depression appears timely.
Methods: This qualitative descriptive study explored the perspectives on late-life depression of 28 private GPs practicing in Singapore through online semi-structured group and individual interviews.
J Dev Phys Disabil
January 2024
School of Rehabilitation Therapy, Queen's University, Louise D. Acton Building, 31 George Street, Kingston, ON K7L 3N6 Canada.
Evidence suggests that integrated support, combining both natural and formal supports, is often essential for individuals with developmental disabilities to achieve their preferred quality of life. However, studies are limited on how to organize supports so that people with developmental disabilities and their families find a balance between formal and natural supports. Often, there are systemic and personal boundaries around the nature and extent of support that can be offered to persons with developmental disabilities through formal mechanisms, yet the value of natural supports in the lives of persons with developmental disabilities is often undervalued in society.
View Article and Find Full Text PDFSAGE Open Med
January 2025
Allergy and Immunology Service Hospitale Maternidade Therezinha de Jesus, Juiz de Fora, Brazil.
Objective: Bacterial extracts have been used for many years to prevent airway infections. Recent findings suggest that immunity can be trained by inducing an immunological memory in both the innate and acquired immune response. This real-life observational study investigated the potential of sublingual bacterial immunotherapy in the prevention of ear, nose, and throat infections.
View Article and Find Full Text PDFCureus
January 2025
Emergency Medicine, Ministry of Health, Riyadh, SAU.
Introduction According to the World Health Organization (WHO), cardiovascular diseases are the leading cause of death globally, accounting for approximately 17 million deaths annually, with sudden cardiac arrest (SCA) as a significant contributor to this alarming statistic. SCA, the abrupt loss of heart function, is a critical medical emergency that requires early recognition and immediate cardiopulmonary resuscitation (CPR) for the effective resuscitation of victims. Various studies have shown a low level of knowledge regarding CPR in the community.
View Article and Find Full Text PDFPopul Res Policy Rev
July 2023
Population Research Institute, Pennsylvania State University, University Park, PA.
Spatially concentrated, vaccine-hesitant populations represent an ongoing challenge to public health policies that emphasize mass vaccination as a means to eradicating certain infectious diseases. Previous research suggests that Amish populations, which are spatially clustered and rapidly growing, may be undervaccinated. However, existing evidence is limited to local case studies in pre-COVID-19 contexts.
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