Fatigue effect

Fatigue effects associated with a long working day has been identified in the context of a 4 day week. 

A number of effects from breathing phenol in air have been reported in humans. Short-term effects reported include respiratory irritation, headaches, and burning eyes. Chronic effects of high exposures included weakness, muscle pain, anorexia, weight loss, and fatigue effects of chronic low-level exposures included increases in respiratory cancer, heart disease, and effects on the immune system. Virtually all of the workplace exposures associated with these effects involved exposures to other chemicals, thus it is difficult to determine whether these are solely due to phenol, or are the result of mixed, multiple, or other chemical exposures. 

The repeated application of the cutting tip to the product applies a local fatiguing effect that reduces significantly the overall force required to break the bonds of the bulk material. 

The Walter Reed Army Institute of Research s Department of Behavioral Biology has developed a field-deployable version of a commercial Psychomotor Vigilance Task (PVT) that has been widely used in sleep research. The software runs on handheld PDAs running the Palm Operating System (Palm OS). It is modeled after the simple reaction time task of Wilkinson and Houghton,57 as modified by Dinges and Powell.58 The Palm OS version incorporates additional stimulus, feedback, control, and data options developed by Dr. Thome. In laboratory studies, performance on the PDA task has been shown to be sensitive to time-on-task fatigue effects, sleep deprivation, and circadian variation.18 Field studies have utilized the PVT to measure the efficacy of caffeine gum as a sleep loss countermeasure. 

PVT performance in sleepy individuals frequently shows the effects of time-on-task on lapse rates at any severity of experimental sleep deprivation (e.g., see Fig. 1). Sleep deprivation can markedly worsen this fatigue effect in PVT performance, regardless of whether the elevated sleep pressure is experimentally induced (5), or through sleep disorders such as the obstructive sleep apnea syndrome (32). Thus, cognitive performance becomes more variable with both time awake and time-on-task (44). 

Orzack MH, Taylor CL, Kometsky C. A research report on the anti-fatigue effects of magnesium pemoline. Psychopharmacology 1968 13 413-417. 

Fig. 48 Notch (fatigue) effect resulting at inserted openings from the application of force. The only crack running through the wall proceeds,...

Figure 48 Notch (fatigue) effect resulting at inserted openings...

I., Magnesium status and parameters of the oxidant-antioxidant balance in patients with chronic fatigue Effects of supplementation with magnesium. J. Am. Coll. Nutr. 19, 374-382 (2000). 

Amax 438 nm). Photocyclization and reversion could be repeated 400 times without any fatigue effect being observed. At the photostationary state, the ratio of 11a to 11b was 18 82. 

Metal Fatigue Effects of Small Defects and Nonmetallic Inclusions ISBN 008-044064-9... 

All types of deformation-uniaxial, biaxial and cyclic uniaxial stretchlng-enhance the photooxidation of LDPE films. A close relationship exists between the enhancement process and the deformation mechanism more disrupture of the structure results in a larger enhancement. Damages such as microcracks, micro-voids, microcrazes-resultlng from disrupture or fatigue effects-increase the degradation rate while orientation decreases it. 

Corrosion fatigue—Occurs when corrosive and fatigue effects occur simultaneously. Corrosion can reduce fatigue life by pitting the surface and propagating cracks. Material selection and fatigue properties are the major considerations. 

What can these systems tell us about cognitive processes in general, and "mental fatigue," an admittedly vague concept, in particular Everyone knows when they feel fatigued, but an objective measure of this construct has yet to be developed. We will assume that work-induced fetigue develops as a function of time-on-task, and that the rate at which fatigue effects appear is a function of the complex interaction between a variety of both subject and task variables. 

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