摘要:

A sample is used to demonstrate that with the aid of heuristic principles, based on the Pergressive Fourier Analysis, rapidly decaying oscillations can be identified in empirical graphs or data. The properties and advantages of this method are explained.

ISSN:0022-1945    

DOI:10.1080/09291018009359711

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

Acetylcholinesterase (AChE) activity of the adenohypophysis, cerebellum, cerebral cortex, hypothalamus, amygdala, hippocampus, midbrain, pons, medulla oblongata and caudate nucleus was determined by a spectro‐photometric method in adult, male rats adapted toan LD 12:12cycle. Results of the study show that AChE activity is highest during the light phase and lowest during the dark phase of the cycle in all the brain areas studied except the adenohypophysis, cerebellum, hippocampus and hypothalamus. These findings expand earlier observations on the circadian variation in rat brain AChE activity and suggests a relationship with reported circadian variation in the acetylcholine levels of rat brain.

ISSN:0022-1945    

DOI:10.1080/09291018009359712

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

A survey is given on two aspects of gene expression in circadian oscillations, (a) The inheritance of rhythm parameters is discussed with special reference to clock mutations, (b) The roles of the nucleus, of transcription, of translation, and the significance of phase‐shifting experiments with inhibitors of protein synthesis are reviewed.

ISSN:0022-1945    

DOI:10.1080/09291018009359713

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

Continuous treatment with high doses of puromycin suppresses the circadian rhythm of bioluminescence inGonyaulax polyedra.When given in sub‐maximal doses, which are inhibitory only in the third or fourth cycle, the antibiotic causes phase delays. At a higher dosage, pulse treatment in different phases results in a phase response curve. Occurrence of phase advance shifts and extent of delay shifts depend on pulse duration. Continuous treatment with a falsifier of transcription, 5‐azacy tidine, causes a reduction in bioluminescence, but does not delay the rhythm. Therefore, the role of protein synthesis in theGonyaulaxclock seems to be predominantly of post‐transcriptional nature.

ISSN:0022-1945    

DOI:10.1080/09291018009359714

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

The physics of the van der Pol oscillator as realized by the Meissner circuit is discussed by analogy to the beat phenomenon and by a consequent analysis of current balance. The current balance method leads to a new, very accurate equation for the dependence of the oscillator frequency on the feedback parameter. Several aspects of entrainment (existence, limited frequency range, dependence on parameters, phase shift) can be explained, too. Numerical results are presented which have been obtained by solving the homogeneous and inhomogeneous van der Pol equation with a Runge‐Kutta method.

ISSN:0022-1945    

DOI:10.1080/09291018009359715

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

In order to investigate the rhythmicity of intermale aggression in mice, and the potential influence of the pineal gland, we maintained 20 male SJL mice who were singly housed in LD 10:14.10 animals were pinealectomized and 10 animals were given sham operations. Pairs of subjects within each group were placed in a testing arena and allowed to fight for 6 minute encounters. Each animal encountered a different member of his group every 27 h so that after 8 days there had been an aggression test for every 3 h of the 24‐h cycle. Beginning on the ninth day the entire test cycle was replicated. During testing five agonistic behaviors were scored for each animal: tail lashing, offensive posture, biting, sniffing and defensive posture. Dominance was also scored on a 5‐point scale. Data were analyzed using factor analysis, multiple regression and analysis of covariance and Mests. Results of the study confirm the hypothesis that agonistic behaviors vary rhythmically in male albino mice. Although pinealectomized mice were significantly rhythmic in fewer behavioral measures than were sham‐operated animals, analysis of covariance did not yield any significant effects of surgical treatment.

ISSN:0022-1945    

DOI:10.1080/09291018009359716

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

Pyrocystis lunula,a dinoflagellate lacking periodicity in spontaneous bio‐luminescence, shows a characteristic circadian rhythm of plastid movements which can be monitored photographically in individual cells. The rhythm persists under free‐running conditions in constant dim light (40–50 Ix), but is damped out already in LL of 100 lx.

ISSN:0022-1945    

DOI:10.1080/09291018009359717

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

ISSN:0022-1945    

DOI:10.1080/09291018009359710

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor