Translate into Russian. 1. Many crystals are phosphorescent, i1. Many crystals are phosphorescent, i. e. they emit light if illuminated, even after the illumination has been discontinued. 2. Many of these substances were found to be phosphorescent, but only if they were crystalline. 3. Whatever the explanation of this phosphorescence, its existence shows definitely that protein molecules, like those of gelatine, can enter into very intimate relations with other low-molecular substances. 4. These experiments were extended to other proteins. It was found that the higher the axial asymmetry, the more elongated the particle. 5. In all these experiments it was always the phosphorescence that disappeared first, followed immediately by the disappearance of DRF. 6. It is these two electrons of the dye which in the first instance take up the energy, liberated by splitting the pyrophosphate bond, transmitting it to the protein. 7. Life in its essence seems to be dependent on this combination of nucleic acid and protein. 8. Apart from being the source of energy it, is also a building- block of the system. 9. ATP is nucleotide, a substance closely related to nucleic acid, and seems to play the same role in actomyosin as nucleic acid does in other structures. 10. It is these small pieces of nucleic acid which we call ATP. 11. Its particles, if discharged, associate side by side. The beautifully crystalline needles turn out to be such aggregates. The ends of the crystal split up, the single myosin particle being too thin to be seen. 12. What is remarkable in these needles is that the finest of them have mostly a length of 2000—4000 Å, tire length calculated for the single myosin particle. 13. The globules are equally inactive in themselves and it is only the system containing the two, skeleton and globules, which is active. 14. The globules, if isolated, have quite extraordinary properties. 15. The first protein, studied somewhat more closely, turned out to be a chromo-protein, a compound of hitherto unknown fluorescent dye and a protein, and it seems possible that other members of this group are built likewise. 16. The meaning of the name «myosin» becomes, under these conditions, somewhat doubtful and already I have been reproached by colleagues for having confused the nomenclature in this field. 17. According to this conception, «myosin» denotes a level of organisation rather than a substance.
UNIT 24 Entropy and Stability Considering non-linear systems we must at first generalize the term 'stationary'. We already mentioned in context with the Stockes law the so-called stationary movement as a movement with constant velocity where the frictional force is equal to the driving force. This sort of movement is also a kind of stationary, i.e. time independent state. The term 'stationary state' can also be applied to states that are not at rest, but show repetitive periodic movements in a stationary manner. For example, cardiac function can be called 'stationary', if the frequency and amplitude of the heart beat does not change during the period of observation. In the case of a linear steady state, fluctuations of the system parameters produce only positive deviations of entropy production, bringing the system back to the stationary state, which is therefore stable in any case. In contrast to this, in the region of non-linear approaches, far from equilibrium, fluctuations of a stationary state can also lead to negative deviations of the entropy production, leading to a destabilization of the system. The system may jump from one into another stationary state. The steady states in the region of nonlinear approaches therefore are mostly metastable. Their stability condition requires the occurrence of only positive deviation of the entropy production. This is the so-called Glansdorff-Prigogine principle. The transition from linear to non-linear approaches of thermodynamics is not only associated with an increase in the coefficient of friction, or with the occurrence of several stationary states, but also with the spontaneous development of so-called dissipative structures. We postulated that there are basically two different types of structures: equilibrium structures (σ= 0), and dissipative structures ( σ > 0). In contrast to equilibrium structures which are always structures in space, dissipative structures can also be structures in time, or in a space-time continuum. This can be illustrated by the function f(v) of a sphere, and the pattern of flow close to it. The laminar flow, which occurs at a low velocity, can be compared with the turbulent flow, which appears when the non-linear region of the function is attained. When the flux-force relation changes from the laminar to the non laminar region, then the unstructured laminar flow becomes unstable and vortices appear which, in the terminology of thermodynamics, are dissipative structures. Define the following words using a dictionary To generalize, linear, stationary, deviation, flux, laminar, to attain, dissipative
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