The manager as a teacher: selected aspects of stimulation of scientific thinking
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EEG alpha rhythm, etc. Sea waves, changes of seasons, movements of planets, movements of trains, etc., - these are all the examples of cyclic recurrence of various systems. The forms of cyclic recurrence curves may be of all sorts. The electrocardiogram curve differs from the arterial pressure curve, and the arterial pressure curve differs from the pressure curve in the aortic ventricle. Variety of cyclic recurrence curves is infinite. Two key parameters characterize recurrence: the period (or its reciprocal variable - frequency) and nonuniformity of the period, which concept includes the notion of frequency harmonics. Nonuniformity of the cycle period should not be resident in SFU (the elementary system) as its performance cycles are always identical. However, the systems have transition periods which may have various cycle periods. Besides, various systems have their own cyclic periods and in process of interaction of systems interference (overlap) of periods may occur. Therefore, additional shifting of own systems periods takes place and harmonics of cycles emerge. The number of such wave overlaps can be arbitrary large. That is why in reality we observe a very wide variety of curves: regular sinusoids, irregular curves, etc. However, any curves can be disintegrated into constituent waves thereof, i.e. disintegration of interference into its components using special analytical methods, e.g. Fourier transformations. Resulting may be a spectrum of simpler waves of a sinusoid type. The more detailed (and more labour-consuming, though) the analysis, the nearer is the form of each component to a sinusoid and the larger is the number of sinusoidal waves with different periods.
The period of system cycle is a very important parameter for understanding the processes occurring in any system, including in living organisms. Its duration depends on time constant of the systems reaction to external impact/influence. Once the system starts recurrent performance cycle, it would not stop until it has not finished it. One may try to affect the system when it has not yet finished the cycle of actions, but the systems reaction to such interference would be inadequate. The speed of the systems functions progression depends completely on the duration of the system performance cycle. The longer the cycle period, the slower the system would transit from one level to another. The concepts of absolute and relative adiaphoria are directly associated with the concept of period and phase of system cycle. If, for example, the myocardium has not finished its “systole-diastole” cycle, extraordinary (pre-term) impulse of rhythm pacemaker or extrasystolic impulse cannot force the ventricle to produce adequate stroke release/discharge. The value of stroke discharge may vary from zero to maximum possible, depending on at which phase of adiphoria period extrasystolic impulse occurs. If the actuating pulse falls on the 2nd and 3rd micro cycles, the myocardium would not react to them at all (absolute adiphoria), since information from the “X” receptor is not measured at the right time. Myocardium, following the contraction, would need, as any other cell would do following its excitation, some time to restore its energy potential (ATP accumulation) and ensure setting of all SFU in “startup” condition. If extraordinary impulse emerges at this time, the systems response might be dependent on the amount of ATP already accumulated or the degree in which actomyosin fibers of myocardium sarcomeres diverged/separated in order to join in the function again (relative adiphoria). Excitability of an unexcited cell is the highest. At the moment of its excitation excitability sharply falls to zero (all SFU in operation, 2nd micro cycle) absolute adiphoria. Thereafter, if there is no subsequent excitation, the system would gradually restore its excitability, while passing through the phases of relative adiphoria up to initial or even higher level (super-excitability, which is not examined in this work) and then again to initial level. Therefore, pulse irregularity may be observed in patients with impaired cardial function, when sphygmic beats are force-wise uneven. Extreme manifestation of such irregularity is the so-called “Jacksons symptom” /pulse deficiency/, i.e. cardiac electric activity is shown on the electrocardiogram, but there is no its mechanical (haemodynamic) analogue on the sphygmogram and sphygmic beats are not felt when palpating the pulse. The main conclusions from all the above are as follows: any systems operate in cycles passing through micro cycles; any system goes through transition process; cycle period may differ in various systems depending on time constant of the systems reaction to the external impact/influence (in living systems on the speed of biochemical reactions and the speed of command/actuating signals); irregularity of the systems cycle period depends on the presence of transition processes, consequently, to a certain degree on the force of external exposure/influence; irregularity of the system cycle period depends on overlapping of cycle periods of interacting systems; upon termination of cycle of actions after single influence the system reverts to the original state, in which it was prior to the beginning of external influence (one single result of action with one single external influence). The latter does not apply to the so-called generating systems. It is associated with the fact that after the result of action has been achieved by the system, it becomes independent of the system which produced it and may become external influence in respect to it. If it is conducted to the external influence entry point of the same system, the latter would again get excited and again produce new result of action (positive feedback, PF). This is how all generators work. Thus, if the first external influence affects the system or external influence is ever changing, the number of functioning SFU systems varies. If no external influence is exerted on the system or is being exerted but is invariable, the number of functioning system SFU would not vary. Based on the above we can draw the definitions of stationary conditions and dynamism of process.
Functional condition of system. Functional condition of the system is defined by the number of active SFU. If all SFU function simultaneously, it shows high functional condition which arises in case of maximum external influence. If none SFU is active it shows minimum functional condition. It may occur in the absence of external influence. External environment always exerts some kind of influence on some systems, including the systems of organism. Even in quiescent state the Earth gravitational force makes part of our muscles work and consequently absolute rest is non-existent. So, when we are kind of in quiescent state we actually are in one of the low level states of physical activity with the corresponding certain low level of functional state of the organism. Any external influence requiring additional vigorous activity would transfer to a new level of a functional condition unless the SFU reserve is exhausted. When new influence is set at a new invariable (stationary) level, functional condition of a system is set on a new invariable (stationary) functional level.
Stationary states/modes. Stationary state is such a mode of systems when one and the same number of SFU function and no change occurs in their functional state. For example, in quiescence state all systems of organism do not change their functional mode as far as about the same number of SFU is operational. A female runner who runs a long distance for quite a long time without changing the speed is also in a stationary state/mode. Her load does not vary and consequently the number of working (functioning) SFU does not change either, i.e. the functional state of her organism does not change. Her organism has already “got used” to this unchangeable loading and as there is no increase of load there is no increase in the number of working SFU, too. The number of working SFU remains constant and therefore the functional state/mode of the organism does not change. What may change in this female runners body is, e.g. the status of tissue energy generation system and the status of tissue energy consumption system, which is in fact the process of exhaustion of organism. However, if the female runner has duly planned her run tactics so that not to find herself in condition of anaerobic metabolism, the condition of external gas metabolism and blood circulation systems would not change. So, regardless of whether or not physical activity is present, but if it does not vary (stationary physical loadings /steady state/, provided it is adequate to the possibilities of the organism), the organism of the subject would be in a stationary state/mode. But if the female runner runs in conditions of anaerobic metabolism the “vicious circle” will be activated and functional condition of her organism will start change steadily to the worse. (The vicious circle is the systems reaction to its own result of action. Its basis is hyper reaction of system to routine influence, since the force of routine external influence is supplemented by the eigen result of action of the system which is independent of the latter and presents external influence in respect to it. Thus, routine external influence plus the influence of the systems own result of action all in all brings about hyper influence resulting in hyper reaction of the system (system overload). The outcome of this reaction is the destruction own SFU coupled with accumulation of defects and progressing decline in the quality of life. At the initial stages while functional reserves are still large, the vicious circle becomes activated under the influence of quite a strong external action (heavy load co