This study examined whether widowhood was associated with physical and mental health, health behaviors, and health outcomes using a cross-sectional (N=72,247) and prospective (N=55,724) design in women aged 50-79 years participating in the Women's Health Initiative observational study (85.4% White). At baseline, married women reported better physical and mental health and generally better health behaviors than widowed women. Whereas women who remained married over the 3-year period showed stability in mental health, recent widows experienced marked impairments and longer term widows showed stability or slight improvements. Both groups of widows reported more unintentional weight loss over the 3-year period. Changes in physical health and health behaviors were inconsistent, with generally small effect sizes. Findings underscore the resilience of older women and their capacity to reestablish connections, but point to the need for services that strengthen social support among women who have difficulty during this transition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
The objective of this study was to examine the effects of hygrothermal aging on the durability of a graphite/epoxy woven composite material system. The study was part of a larger project in which the objective was to evaluate and model the effects of moisture, temperature, and combined hygrothermal conditions on the strength and life of a graphite/epoxy woven composite material system. The results presented here represent an extension of the work by Patel and Case (Int. J. Fatigue 22 (2000) 809).
The hygrothermal aging consisted of cyclical temperature and moisture variations which were meant to simulate mission conditions for an advanced subsonic aircraft. Durability studies were carried out on the aged material system in the form of fatigue and residual strength testing under humid and elevated temperature environments. Damage mechanisms and failure modes were determined through fatigue testing, residual strength testing, and nondestructive evaluation.
Changes in physical appearance, thermal analysis results, fracture surfaces, and moisture diffusion behavior all supported the idea that the material was affected by the aging process. However, experimental testing also showed that the initial and residual tensile properties of the aged material were virtually unaffected by the imposed environmental aging (as compared to unaged material testing results), except when tested at elevated temperature. At elevated temperature, both the dynamic stiffness and residual strength were noticeably reduced from that at room temperature. 相似文献
In this work, the filiform corrosion behaviour of powder painted aluminium profiles was studied, and the coating barrier properties together with adhesion to the substrate were analysed. Samples coated with a traditional painting procedure (one powder layer application followed by curing), and other samples coated using a special cycle to obtain wood grain effect were compared using accelerated filiform corrosion tests. Moreover, in order to better understand the degradation mechanisms of painted metal substrates, thermal stresses were applied to accelerate the natural weathering. The effects of the thermal aging were analysed by electrochemical impedance spectroscopy. 相似文献