Aging failure effects

Seismic Vuinerabiiity Assessment Reinforced Con- joint failure on the sub-assemblage (b) effect of anchor-crete Structures, Fig. 10 Experimental results of age failure (Adapted from Pantelides et al. 2002) unreinforced exterior joint (a) effect of beam-column... 

Fig. 10. Long-term effect of aging in vacuum on flexibiUty of Parylenes C, D, and N at elevated temperature. Failure = 50% loss in tensile strength.

This report provides an aging assessment of electric motors and was conducted under the auspices of the USNRC NPAR. Pertinent failure-related information was derived from LERs, IPRDS, NPRDS, and NPE including failure modes, mechanisms, and causes for motor problems. In addition, motor design and materials of construction were reviewed to identify age-sensitive components. The study included consideration of the seismic susceptibility of age-degraded motor components to externally-induced vibrational effects. 

Effect of Age on Failure Strain for Various Strain Rates. . P 429... 

Fig 14 Effect of age on failure strain for various strain rates... 

The corticosteroids are administered with caution in older adults because they are more likely to have preexisting conditions such as congestive heart failure, hypertension, osteo-poros s and arthritis which may be worsened by the use of such agents The nurse monitors older adults for exacerbation of existing conditionsduring corticosteroid therapy. In addition, lower dosages may be needed because of the effects of aging, such as decreased muscle mass renal function, and plasma volume. 

An in vitro study demonstrated that cadmium and zinc have an antagonistic effect on the inhibitory effects of lead on human ALAD activity (Davis and Avram 1978). Cadmium was 40-100 times more potent than zinc in activating ALAD. Furthermore, the combined effects of cadmium and lead in tissue resulted in an additively increased risk of mortality related to cardiac failure in humans with significant relation to age in 80% of the cases (Voors et al. 1982). 

In Parkinson s disease very few studies focus on the elderly although Parkinson s disease is significantly age-related (SBU 2003). In the studies few patients suffers mental side effects of the drugs, while in clinical practice almost half of elderly patients suffers such problems. Since the studies do not include patients with co-morbidity it does not reflect the clinical situation. In heart failure modern treatment recommendations are based on studies were the average age of the patients are 60-65 years, most of which did not even include patients over 80 (SBU 2003). 

Here treatment results in a somewhat earlier onset of a condition which occurs eventually in all animals. Failure to age-adjust will result in a comparison of 29/50 with 21/50, which is not statistically significant. Age adjustment will essentially ignore the early and late deaths, which contribute no comparative statistical information, and be based on the comparison of 9/10 with 1/10, which is statistically significant. Here age adjustment sharpens the contrast, rather than avoiding bias, by avoiding diluting data capable of detecting treatment effects with data that are of little or no value for this purpose. 

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