fourier transform infrared (ftir) and gel permeation chromatography (gpc) wre respectively utilized in determining the changes in isocyanate (nco) concentration and molecular weight (mw) and its distribution (mwd) in polyurethanes during their cure and postcure stages. samples, originally cured at 45°c, were taken through accelerate aging tests at various temperatures. the ftir and gpc analytic...

deterioration of seed is one of the most important limiting or even hindering factors in its germination. an evaluation and understanding of the factors responsible for/ and enhancing seed deterioration is of paramount importance. the main aim of this study was to determine the effects of seed deterioration on its germination and as well on the activities of antioxidant enzymes in canola culitv...

Several metabolic alterations accumulate over time along with a reduction in biological fitness, suggesting the existence of a "metabolic clock" that controls aging. Multiple inborn defects in metabolic circuitries accelerate aging, whereas genetic loci linked to exceptional longevity influence metabolism. Each of the nine hallmarks of aging is connected to undesirable metabolic alterations. Th...

The relationships between reproduction and aging are important for understanding the mechanisms of aging and evaluating evolutionary theories of aging. To investigate the effects of progeny production on reproductive and somatic aging, we conducted longitudinal studies of Caenorhabditis elegans hermaphrodites. For mated wild-type animals that were not sperm limited and survived past the end of ...

based on both animal and human studies, inequality in food intake and social instability has adverse effects on the health of individuals and the community. however, it is not known whether social instability, food deprivation and food inequality affect neuronal death and premature aging in young animals. to address this question, the effects of these adverse situations, histopathological chang...