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Related Concept Videos

Pulse rhythm01:30

Pulse rhythm

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Pulse rhythm refers to the pattern of pulsations within specific intervals, offering valuable insights into the regularity or irregularity of the heart's beats as observed through the pattern of pulsation within specific intervals. A regular pulse exhibits a consistent heart rate with uniform waveforms and pulsation force, variations of which can be classified as normal, weak, or bounding.
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Arrhythmia or dysrhythmia refers to an abnormal heart rhythm caused by a defect in the heart's conduction system. It can cause the heart to beat irregularly, too quickly, or too slowly, leading to symptoms like chest pain, shortness of breath, and fainting. Factors such as stress, caffeine, alcohol, nicotine, cocaine, certain drugs, congenital defects, diseases, and electrolyte abnormalities can trigger arrhythmias.
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An electrocardiogram (ECG)graphically represents the heart's electrical activity on ECG paper or a monitor.
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The normal cardiac rhythm is a synchronized electrical activity that facilitates the regular and coordinated contraction of the heart muscle. This process is essential for efficient blood circulation throughout the body. The fundamental elements involved in establishing and maintaining this rhythm include the unique electrical properties of cardiac muscle cells, the sinoatrial (SA) node's pacemaker function, the specialized conducting system, and the ionic mechanisms underlying each phase...
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The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent...
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Respiratory Depth
Respiratory depth measures the volume of air inhaled or exhaled during a breath. It can vary from shallow to deep and typically remains consistent when a person is at rest or asleep. Occasionally, individuals will automatically inhale deeply, known as sighing, which inflates the lungs with more air than normal breathing.
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Using Learning Outcome Measures to assess Doctoral Nursing Education
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Shift Work, Chronotype, and Melatonin Rhythm in Nurses.

Pedram Razavi1, Elizabeth E Devore2, Archna Bajaj3

  • 1Department of Medicine and Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, New York.

Cancer Epidemiology, Biomarkers & Prevention : a Publication of the American Association for Cancer Research, Cosponsored by the American Society of Preventive Oncology
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Summary
This summary is machine-generated.

Night-shift work disrupts melatonin levels, especially in evening chronotypes. Aligning shift work with an individual's natural chronotype may mitigate these effects.

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Area of Science:

  • Chronobiology
  • Occupational Health
  • Melatonin Research

Background:

  • Previous research links night-shift work to melatonin disruption.
  • Evidence on how chronotype influences this relationship is mixed.

Purpose of the Study:

  • To investigate the combined effects of rotating shift work and chronotype on melatonin secretion patterns.
  • To assess light exposure and urinary melatonin metabolite levels in nurses.

Main Methods:

  • 130 nurses (rotating-shift and day-shift) wore light meters and provided urine samples over 3 days.
  • Assessed 6-sulfatoxymelatonin (aMT6s), a key urinary melatonin metabolite.
  • Analyzed light exposure, urinary melatonin levels, peak concentration, and timing.

Main Results:

  • Rotating-shift workers experienced higher light exposure and lower night-time melatonin levels compared to day-shift workers.
  • Melatonin rhythms showed smaller peaks and later onset in rotating-shift workers.
  • Chronotype significantly interacted with shift work type, influencing melatonin rhythm parameters (P < 0.05).

Conclusions:

  • Rotating shift work, particularly at night, leads to increased light exposure and suppressed melatonin.
  • Melatonin disruption is influenced by both shift work and individual chronotype.
  • Better alignment between shift work schedules and chronotype may reduce melatonin disruption.