Related Experiment Video
Updated: Jan 20, 2026

Recording and Analysis of Circadian Rhythms in Running-wheel Activity in Rodents
Published on: January 24, 2013
Retraction: Effects of Sodium Lighting on Circadian Rhythms in Rats
Xian Chen1, Chang-Ning Liu2, Judith E Fenyk-Melody1
1Comparative Medicine, Pfizer Worldwide Research and Development, Cambridge, Massachusetts.
Abstract:
This retracts the article entitled, "Effects of Sodium Lighting on Circadian Rhythms in Rats" by Xian Chen, Chang-Ning Liu, and Judith E Fenyk-Melody published in the May issue vol 58, issue 3, p 311-320. This article is being retracted with the support of all 3 coauthors due to methodological and authorship issues.
Related Concept Videos
Circadian Rhythms and Gene Regulation
Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...
Clot Retraction and Fibrinolysis
Pulse rhythm
Conversely, an irregular pulse pattern is termed dysrhythmia, stemming from disruptions in cardiac...
Disturbances in Heart Rhythm
Arrhythmias are categorized by their speed, rhythm, and origin. A slow heart...
ECG Interpretation of Rhythms
Components of the Electrocardiogram
The primary components of a normal ECG waveform in Normal sinus rhythm(NSR) include the P wave, PR interval, QRS complex, ST segment, T wave, and occasionally a U wave.
ECG waveforms are divided by vertical and horizontal lines at standard intervals.
The horizontal axis measures time and rate, and the vertical axis measures amplitude or voltage....

