The second signal system as conceived by Pavlov and his disciples

1990 ◽  
Vol 25 (4) ◽  
pp. 163-173
Author(s):  
George Windholz
Keyword(s):  
Signal System

Adaptive & Coordinated Traffic Signal System

2020 ◽  
Author(s):  
S.U. Dampage ◽  
T.D. Munasingha ◽  
W.D.K Gunathilake ◽  
A.G. Weerasundara ◽  
D.P.D Udugahapattuwa
Keyword(s):  
Traffic Signal ◽  
Signal System

Fluoxetine increases the activity of the ERK-CREB signal system and alleviates the depressive-like behavior in rats exposed to chronic forced swim stress

2008 ◽  
Vol 31 (2) ◽  
pp. 278-285 ◽  
Author(s):  
Xiaoli Qi ◽  
Wenjuan Lin ◽  
Junfa Li ◽  
Huanhuan Li ◽  
Weiwen Wang ◽  
...  
Keyword(s):  
Signal System ◽  
Swim Stress ◽  
Forced Swim ◽  
Forced Swim Stress

Sex-chromosome anaphase movements in crane-fly spermatocytes are coordinated: ultraviolet microbeam irradiation of one kinetochore of one sex chromosome blocks the movements of both sex chromosomes

1987 ◽  
Vol 88 (4) ◽  
pp. 441-452
Author(s):  
JULIA A. M. SWEDAK ◽  
ARTHUR FORER
Keyword(s):  
Sex Chromosomes ◽  
Sex Chromosome ◽  
The Other ◽  
Signal System ◽  
Spindle Fibre ◽  
Spindle Axis ◽  
Ultraviolet Microbeam ◽  
Block Motion ◽  
Block Movement ◽  
Spindle Fibres

Sex chromosomes in crane-fly spermatocytes move polewards at anaphase after the autosomes have reached the poles. In Nephrotoma abbreviate the sex chromosomes are 8 μm long by 3.5 μm wide and have two orientations when they move: the long axis of the sex chromosome is either perpendicular or parallel to the spindle axis. We assume (1) that when a sex chromosome is perpendicular to the spindle axis it has a chromosomal spindle fibre to each pole, one from each kinetochore, as in other species; and (2) that when a sex chromosome is parallel to the spindle axis each kinetochore has spindle fibres to both poles, i.e. that the latter sex chromosomes are maloriented. We irradiated one kinetochore of one sex chromosome using an ultraviolet microbeam. When both sex chromosomes were normally oriented, irradiation of a single kinetochore permanently blocked movement of both sex chromosomes. Irradiation of non-kinetochore chromosomal regions or of spindle fibres did not block movement, or blocked movement only temporarily. We argue that ultraviolet irradiation of one kinetochore blocks movement of both sex chromosomes because of effects on a ‘signal’ system. The results were different when one sex chromosome was maloriented. Irradiation of one kinetochore of a maloriented sex chromosome did not block motion of either sex chromosome. On the other hand, irradiation of one kinetochore of a normally oriented sex chromosome permanently blocked motion of both that sex chromosome and the maloriented sex chromosome. We argue that for the signal system to allow the sex chromosomes to move to the pole each sex chromosome must have one spindle fibre to each pole.

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