BACKGROUND We evaluated the influence of chemical disinfection and accelerated aging on the dimensional stability and detail reproduction of a silicone elastomer containing one of two opacifiers. METHODS A total of 90 samples were fabricated from Silastic MDX 4-4210 silicone and divided into groups (n = 10) according to opacifier content (barium sulfate or titanium dioxide) and disinfectant s...

the static strain aging is a phenomenon that can change the mechanical properties of low carbon steels. thus, the static strain aging behavior of low carbon steel wires after drawing process is studied. to do so, the wires are austenitized at different temperatures and cooled in different rates. then the wires are drawn and aged at a specific temperature and time. before and after aging of each...

Aging is an inevitable irreversible process in all human population. With the aging individuals become cognitively less agile and effects of decline noted their various abilities to do Activities Daily Living. This study was done investigate co-relation between performance on cognitive linguistic tasks CLAP-M test Lawton instrumental activities daily living scale a sample geriatric population, ...

The wide disparity in longevity observed across species indicates that aging is a species characteristic. However, the obvious fitness costs of aging on individual reproduction would cause strong selection pressure against it. In this paper we have developed an adaptive hypothesis of aging for the sake of group diversity. Our hypothesis relies on a group selection mechanism, which we argue supe...

This article reviews the empirical studies that test socioemotional aging across cultures. The review focuses on comparisons between Western (mostly North Americans and Germans) and Eastern cultures (mostly Chinese) in areas including age-related personality, social relationships, and cognition. Based on the review, I argue that aging is a meaning-making process. Individuals from each cultural ...

M aintaining balance is essential to carrying out daily tasks without falling. This review will describe the impact of impaired postural control on older adults, operationalize what is meant by postural control, and outline postural control test batteries. Findings from highly quantitative, laboratorybased studies will be discussed because these data serve as the foundation of knowledge regardi...

In order to obtain a reliable estimate of the lifetime of the BaBar drift chamber, a dedicated aging test chamber has been constructed. The working gas mixture is Helium/Isobutane (80/20). After accumulating up to 0.11C/cm charge dose the anode wire showed no appreciable signs of aging, but the field wires showed a small Malter effect. At 0.2C/cm the gas gain dropped B6–9% and the Malter effect...

We test the quasiequilibrium picture of the aging dynamics--strictly valid in the asymptotic dynamical regime of aging systems--in the preasymptotic aging regime of the two-dimensional Edwards-Anderson spin glass model. We compare the fluctuation-dissipation characteristic for spin autocorrelation function and response with a corresponding one obtained for a suitably defined correlation functio...

All multicellular organisms undergo a decline in tissue and organ function as they age. An attractive theory is that a loss in stem cell number and/or activity over time causes this decline. In accordance with this theory, aging phenotypes have been described for stem cells of multiple tissues, including those of the hematopoietic system, intestine, muscle, brain, skin and germline. Here, we di...

The nematode Caenorhabditis elegans is excellently suited as a model for studying the genetic and molecular genetic basis of aging, and to test chemical compounds that interfere with the aging process. Mutants of factors in both the insulin and target of rapamycin (TOR) signalling pathways have been shown to extend life span of the worm. Phenotypic similarities among those mutants suggested tha...