Plans for orbital study of rat biorhythms results of interest beyond the biosatellite program

Halberg, Franz; Nelson, W. W.; Runge, Walter; Schmitt, Otto H.; Pitts, G. C.; Tremor, J. W.; Reynolds, Orr E.

doi:10.1007/bf00941362

Cited by 24 publications

(11 citation statements)

References 12 publications

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“…The rats I studied in continuous darkness had periods very close to 24 hours, in my hands usually 24.1–24.3 hours, lengthening with increased light intensity [146], in keeping with "Aschoff's rule" concerning rodents which Aschoff had earlier postulated and documented. After 1960, however, Curt Richter found free-running, as Colin Pittendrigh had earlier, and Aschoff before that [147].…”

Section: Introductionmentioning

confidence: 53%

Transdisciplinary unifying implications of circadian findings in the 1950s

Halberg

Cornélissen

Katinas

et al. 2003

J Circadian Rhythms

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101

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A few puzzles relating to a small fraction of my endeavors in the 1950s are summarized herein, with answers to a few questions of the Editor-in-Chief, to suggest that the rules of variability in time complement the rules of genetics as a biological variability in space. I advocate to replace truisms such as a relative constancy or homeostasis, that have served bioscience very well for very long. They were never intended, however, to lower a curtain of ignorance over everyday physiology. In raising these curtains, we unveil a range of dynamics, resolvable in the data collection and as-onegoes analysis by computers built into smaller and smaller devices, for a continued self-surveillance of the normal and for an individualized detection of the abnormal. The current medical art based on spotchecks interpreted by reference to a time-unqualified normal range can become a science of time series with tests relating to the individual in inferential statistical terms. This is already doable for the case of blood pressure, but eventually should become possible for many other variables interpreted today only based on the quicksand of clinical trials on groups. These ignore individual differences and hence the individual's needs. Chronomics (mapping time structures) with the major aim of quantifying normalcy by dynamic reference values for detecting earliest risk elevation, also yields the dividend of allowing molecular biology to focus on the normal as well as on the grossly abnormal.

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Section: Introductionmentioning

confidence: 53%

Transdisciplinary unifying implications of circadian findings in the 1950s

Halberg

Cornélissen

Katinas

et al. 2003

J Circadian Rhythms

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101

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“…Also of comparative physiologic interest are the results reported earlier for other organisms, variables, and approaches (1,2,7,13), notably those that show convincingly that, following manipulation of the lighting regimen, a shift of rhythm in one direction usually occurs much more quickly than an adjustment in the opposite direction. Such a polarity of directedness in phase adiustment (7) Drobably is related to the stage of the circadian system when the phase shifting stimulus is applied.…”

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confidence: 78%

“…In the meantime, progress also has been made toward quantifying rhythms by objective methods which included inferential statistical techniques for interpreting the data (4,10). In this communication, serial cosinors (7) are introduced into the analysis of circadian pinnule rhythms, to focus especially on their phase shifting following advances and delays in lighting schedule. The extent of precision and reproducibility of this objective technique as applied to a plant rhythm, and differences in phase shift behavior thus assessed, are the two major points presented.…”

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confidence: 99%

“…Such a polarity of directedness in phase adiustment (7) Drobably is related to the stage of the circadian system when the phase shifting stimulus is applied. The circadian system phase indeed critically determines the outcome of adjustment subsequent to stimulation in many cases, as documented by drastic differences in response not only to light but also to a variety of agents-noise, drugs, bacterial endotoxins, to cite but a few examples (1,5).…”

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Quantifying Rhythmic Movements of Albizzia julibrissin Pinnules

1973

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The cosinor technique, previously applied to studies of animal rhythms, is used to assess the circadian rhythm in pinnule movement of Albizzia julibrissin. The method provides a quantitative approach for studying rhythm properties of either intact or excised pinnules. Phase shifting in A. julibrissin, as compared to the usually slower phase shifts of various circadian phenomena in the insect, bird, and mammal, occurs within 1 day or two. Rhythm adjustment in the pinnules takes place more rapidly when the lighting regiment is advanced than when it is delayed.Leaf movement rhythms have long been studied by exclusive reliance upon inspection of data recorded in time plots (1, 3). In the meantime, progress also has been made toward quantifying rhythms by objective methods which included inferential statistical techniques for interpreting the data (4, 10). In this communication, serial cosinors (7) are introduced into the analysis of circadian pinnule rhythms, to focus especially on their phase shifting following advances and delays in lighting schedule. The extent of precision and reproducibility of this objective technique as applied to a plant rhythm, and differences in phase shift behavior thus assessed, are the two major points presented.MATERIALS AND METHODS Albizzia julibrissin plants were propagated from seeds and kept in the greenhouse for spans of varying lengths (weeks to months); however, to be included for study, a plant had to have two or more mature leaves. Plants were transferred to growth chambers at least 3 days before each study and were

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“…When investigating several mammalian and avian species, it was discovered that after 12 hour phase shifts, the majority of individuals re-entrained by phase delays (Pohl, 1978). In nocturnal rodents, re-entrainment following a phase delay normally occurs faster than after a phase advance (Aschoff et al, 1975;Halberg et al, 1971;Daan 1976, Schöttner et al, 2011). The difference in rate of re-entrainment between the two species may be ascribed to species differences in the plasticity of the circadian clock.…”

Section: Discussionmentioning

confidence: 99%

A tale of two jirds: The locomotory activity patterns of the King jird (Meriones rex) and Lybian jird (Meriones lybicus) from Saudi Arabia

Alagaili

Mohammed

Bennett

et al. 2013

Journal of Arid Environments

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The animal-environment interaction is complex, and the ability to temporally organise locomotor activity provides adaptive and survival advantages. We investigated daily and circadian locomotor activity patterns of two jird species from Arabia occurring in dramatically different environments to determine the environmental effect on activity. The King jird occurs in mountainous regions of Azir where climatic conditions are cool and wet, while the Libyan jird inhabits low-lying hot sandy deserts where temperatures exceed 45ºC during summer.Six King jirds and nine Libyan jirds were subjected to a 12L:12D light cycle, a period of constant darkness (DD) and an inversed 12D:12L light cycle. Five of six King jirds and all Libyan jirds showed entrainment of their activity to the light cycles, most animals exhibited nocturnal activity. All entraining jirds showed circadian rhythmicity, with the periods of the rhythms very close to 24 hours. Entraining jirds inversed their activity patterns when the light cycle was inversed. The two jird species displayed comparable amounts of nocturnal activity in all light cycles presented. The King jird showed larger intraspecific variability than the Libyan jird, which may reflect more plasticity in its circadian clock, allowing it to adapt quicker to environmental changes.

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Plans for orbital study of rat biorhythms results of interest beyond the biosatellite program

Cited by 24 publications

References 12 publications

Transdisciplinary unifying implications of circadian findings in the 1950s

Transdisciplinary unifying implications of circadian findings in the 1950s

Quantifying Rhythmic Movements of Albizzia julibrissin Pinnules

A tale of two jirds: The locomotory activity patterns of the King jird (Meriones rex) and Lybian jird (Meriones lybicus) from Saudi Arabia

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