ISSN:0022-1945    

DOI:10.1080/09291018109359719

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

The secular cycle of solar activity is related to the sun's oscillatory motion about the center of mass of the solar system. Comparatively short periods of revolution with relatively high rates of curvature constitute a potential for crucial values of the time integral of torque ?L =?t1t0τ (t) dtwhich seem to give rise to a weak but long lasting flow of solar plasma that modulates short‐term flow due to the dynamo effect. Relatively strong impulses of the torque ?Loccur at mean intervals of 19.86 years. Four consecutive impulses respectively define a permanent wave with a quasiperiod of 79.46 years which determines the distribution of positive and negative extrema in activity. Phases of 0° or 90° indicate a potential for peaks and phases of 180° or 270° can lead to troughs. Such potentials are actually released if ?Ltransgresses a definite threshold value. The ensuing interval variations in the secular cycle are verified by records of sunspots and aurorae dating back to the 4th century AD. Rare activity‐deficient periods like the Maunder Minimum, which according to Eddy et al. are related to changes in the Earth's climate, solely occur when ?Lreaches exceptional values meeting a special criterion. This is confirmed by radiocarbon data going back to the 6th millenimum BC. The next minimum in the 79‐year cycle will occur in 1990. It will be more pronounced than the minimum in 1811.

ISSN:0022-1945    

DOI:10.1080/09291018109359720

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

A long‐period data set (1880–1970) of mean annual temperatures and precipitation totals for over 100 stations worldwide distributed was used to calculate time series of zonal means at 10 degree latitude bands. Power spectra of these zonally averaged series display the following features: over most of the earth zonal mean annual temperatures undergo long‐term climatic fluctuations (≥22 years).

ISSN:0022-1945    

DOI:10.1080/09291018109359721

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Various substances potentially acting on membranes were tested for their capability of phase shifting the free‐running bioluminescence rhythm inGonyaulax polyedra.Quinidine, propranolol, 1‐aminoadamantane, and to a certain extent also tetracaine showed similar tendencies in their effects: suppression of bioluminescence and, hence, suppression of apparent rhythmicity at high concentrations, phase advance shifts together with gradual reduction of bioluminescence at lower concentrations. After pulses with 5 x 10‐5M quinidine, the rhythm was still apparent for several periods, although absolute bioluminescence values were reduced. Variation of the phase of pulse treatment resulted in a phase response curve.

ISSN:0022-1945    

DOI:10.1080/09291018109359722

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

We investigated the diurnal rhythmicity ofin vitrotranslated mRNAs for integral membrane proteins. Microsomes were isolated from rat liver in different phases of the 24‐h cycle. The polysomal mRNA was translated in a hepaticin vitrosystem containing tRNA, pH 5 enzyme, Sephadex G‐25 eluate, an ATP regenerating system, GTP, spermidine, controlled concentrations of amino acids, and3H leucine. After translation, the membranes were freed from extrinsic proteins by treatment with EDTA and high LiCl. Integral proteins were extracted from the membrane vesicles by SDS, and separated by polyacrylamide gel electrophoresis.3H leucine incorporation into various individual integral membrane proteins revealed diurnal rhythms in the corresponding mRNA activities.

ISSN:0022-1945    

DOI:10.1080/09291018109359723

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

The caecotrophy rhythm of 15 male rabbits was registered continuously for 320 days at 5 different LD schedules (LD 12:12, LL, LD 23:1, LD 11:1 + 11:1, LD 12:12). The results were compared with the preceding experiment of the reverse set‐up. The following results were obtained:1.The caecotrophy rhythm, biphasic during LD 12:12, ran free mono‐phasically in all animals.2.Aftereffects of the preceding LD 12:12 were present for up to 52 days, affecting the length of the free‐running period significantly.3.The insertion of the 60‐minute scotoperiod schedule was responded by delay shifts, the signal meeting the free‐running rhythm during the early subjective night, and by advance shifts, when the signal occurred during the late subjective night.4.Eight animals did entrain with the 60‐minute scotoperiod. The average phase angle difference was negative; both the interindividual and intra‐individual scatters were very high.5.Seven animals did not entrain with the LD 23:1 but exhibited an oscillatory free‐run.6.During the skeleton scotoperiod only 6 animals showed stable entrainment, 9 animals failed to entrain with this Zeitgeber.7.The comparison of the phase angles during the 60‐minute scoto‐ and photoperiod experiments, the respective skeleton‐photoperiod experiments and the complete LD 12:12 schedules indicates that the phase angle difference becomes more negative at an increasing LD ratio in the rabbit.8.The results suggest that a sceleton photoperiod is nearly as strong a Zeitgeber as a complete LD 12:12 and that Zeitgeber strength decreases from LD 1:23 to LD 23:1 to LD 11:1 + 11:1.9.The oscillatory free‐run can be explained reasonably on the assumption of a more pronounced delay section of the phase response curve in these rabbits.

ISSN:0022-1945    

DOI:10.1080/09291018109359724

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Thyroid stimulating hormone (TSH) serum levels in 16 elderly patients with outcomes of cerebral atherosclerosis and in 14 adult apparently healthy subjects have been analyzed. Samples of venous blood were drawn every 4 h during the same day, starting at 0000. Results were evaluated by “single cosinor”; and “population mean cosinor”; methods. In addition, chronodesms (time‐specified tolerance invervals) were computed. A statistically significant circadian rhythm of serum TSH has been detected only in adult healthy subjects, but not in elderly patients. These results are discussed considering: a) desynchronization within the group and/or of the single subject studied; b) age effect; c) the interference of the thyroid function in this disease.

ISSN:0022-1945    

DOI:10.1080/09291018109359725

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Artifacts of fetal EEG induced by labour activities become more difficult in computerized analysis. The algorithm described bases on a Fast Fourier Transformation whereby the artificial frequencies will be eliminated successively. A following inverse Fast Fourier Transformation allows to decide the range of monitored frequencies not initiated by fetal EEG.

ISSN:0022-1945    

DOI:10.1080/09291018109359726

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Longitudinal studies of the electrocardiogram (ECG) have been carried out on ten subjects. The results were analysed using a microprocessor system and rhythmic variations in some of the ECG parameters were observed. The cycles were found to lie with periods ranging from six to forty days.

ISSN:0022-1945    

DOI:10.1080/09291018109359727

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

The movements ofOxalis acetosellaandO. regnelliiare narrowed by physiological limits revealing a shape of nearly a square wave. Profound seasonal alterations of the steepness of the two slopes point to the absence of a single limit‐cycle oscillation driving leaf movement.

ISSN:0022-1945    

DOI:10.1080/09291018109359728

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor