A preliminary study of the effects from age and dehydration on fatigue crack growth in human dentin was conducted. Compact tension (CT) fatigue specimens of coronal dentin were prepared from extracted molars and subjected to high cycle fatigue (10(5)<N<10(6)) under Mode I loading. Young hydrated dentin (mean age=25+/-7 years), old hydrated dentin (mean age=55+/-14 years) and young dehydrated de...

A flexural model of four-point bending fatigue that has been experimentally validated for human cortical bone under load control was used to determine how load and displacement control testing affects the fatigue behavior of human cortical bone in three-point and symmetric four-point bending. Under load control, it was predicted that three-point bending produced no significant differences in fa...

conclusions people with chronic kidney disease regardless of their age, gender, state of health, and duration of hemodialysis experience high levels of fatigue; it is particularly important for health providers to understand this level of fatigue which affects the daily life of patients. results all the patients experienced degrees of fatigue and 50 (30.7%) of the participants experienced a hig...

Fatigue is a pervasive, protective phenomenon affecting the totality of the individual. Assessment and management involve a wide range of activities to address the total human being's physical, psychological, cognitive, and spiritual dimensions. When elimination or neutralization of the effect of an antecedent condition is not an option, redesigning one's life-style may be the primary avenue of...

Although human dentin is known to be susceptible to failure under repetitive cyclic fatigue loading, there are few reports in the literature that reliably quantify this phenomenon. This study seeks to address the paucity of fatigue data through a systematic investigation of the effects of prolonged cyclical loading on human dentin in an environment of ambient temperature Hank's balanced salt so...

Directed attention plays an important role in human information processing; its fatigue, in turn, has farreaching consequences. Attention Restoration Theory provides an analysis of the kinds of experiences that lead to recovery from such fatigue. Natural environments turn out to be particularly rich in the characteristics necessary for restorative experiences. An integrative framework is propos...

Directed attention plays an important role in human information processing; its fatigue, in turn, has far­ reaching consequences. Attention Restoration Theory provides an analysis of the kinds of experiences that lead to recovery from such fatigue. Natural environments turn out to be particularly rich in the character­ istics necessary for restorative experiences. An integrative framework is pr...