Millisecond pulsars: nature's most stable clocks
Article Abstract:
Millisecond pulsars are rapidly rotating neutron stars. These spherical flywheels, discovered in 1967, produce clock-like pulses of broadband radio noise from discrete directions in the sky. They are some 20Km in diameter, 1.4 times more massive than the sun and spin as fast as several thousand radians per second. The noise is generated in a magnetosphere by a highly beamed process. It is detectable over interstellar distances as a clock-like periodic sequence of pulses. Some pulsars have fractional stabilities that compare with those of the best atomic clocks. Millisecond pulsar observations should help to establish frequency and time scales with long-term stabilities.
Publication Name: Proceedings of the IEEE
Subject: Electronics
ISSN: 0018-9219
Year: 1991
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Business juggles many balls with medical-exam rules
Article Abstract:
The Americans with Disabilities Act requires employers to provide medical evaluations for applicants and current employees to determine fitness for work, detect work-related injury and promote health. Medical examinations should also include a thorough physical examination, work and medical history, drug testing, strength and endurance testing. Proper employee placement based on examination results saves employers from incurring substantial liability costs.
Publication Name: Safety & Health
Subject: Health
ISSN: 0891-1797
Year: 1992
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Predictors of perceived coping effectiveness in patients awaiting a heart transplant
Article Abstract:
The effective coping in patients awaiting a heart transplant (HT) is determined by factors like coping styles, social support, HT wait, prognosis and transplant status.
Publication Name: Nursing Research (New York)
Subject: News, opinion and commentary
ISSN: 0029-6562
Year: 2007
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