Pumps mechanical impulse

Mechanical Impulse The principle of mechanical impulse when applied to fluids is usually combined with one of the other means of imparting motion. As mentioned earher, this is the case in axial-flow compressors and pumps. The turbine or regenerative-type pump is another device which functions partially oy mechanical impulse. 

ATP is used not only to power muscle contraction, but also to re-establish the resting state of the cell. At the end of the contraction cycle, calcium must be transported back into the sarcoplasmic reticulum, a process which is ATP driven by an active pump mechanism. Additionally, an active sodium-potassium ATPase pump is required to reset the membrane potential by extruding sodium from the sarcoplasm after each wave of depolarization. When cytoplasmic Ca2- falls, tropomyosin takes up its original position on the actin and prevents myosin binding and the muscle relaxes. Once back in the sarcoplasmic reticulum, calcium binds with a protein called calsequestrin, where it remains until the muscle is again stimulated by a neural impulse leading to calcium release into the cytosol and the cycle repeats. 

Up-Pumping [1,74]. As already mentioned in Sect. 3.1, the author consulted a number of specialists in advance about his ideas. However, in this way he introduced into his model the ideas of primary fragmentation of EMs under extreme conditions. Nevertheless, he enriched the theory of initiation of explosive transformations of EMs by introducing significant ideas about transfer of initiation impulse to molecules in the crystal lattice of these materials. Experimental verification of this model is absent to date. In Dlott s opinion [1,74] the initiation by impact is a particular case of initiation by mechanical impulses (Low Velocity Initiation). Also [105] (Sect. 3.3.4) clearly documents the difference between the initiations by impact and by shock, though the authors do not call attention to this fact. Both the cited facts agree with study results of initiation reactivity of polynitro compounds by means of physical organic chemistry (Sects. 4.7 and 4.11), where the initiation by impact is treated separately from the set of initiations by shock, electric spark and heat. 

FIGURE 6-39. Mechanism of action of serotonin selective reuptake inhibitors (SSRIs)—part 5. Finally, once the SSRIs have blocked the reuptake pump (Fig. 6-36), increased somatodendritic serotonin (Fig. 6-36), desensitized somatodendritic serotonin 1A autoreceptors (Fig. 6—37), turned on neuronal impulse flow (Fig. 6-38), and increased release of serotonin from axon terminals (Fig. 6— 38), the final step shown here may be the desensitization of postsynaptic serotonin receptors. This has also been shown in previous figures demonstrating the actions of monoamine oxidase (MAO) inhibitors (Fig. 6-4) and the actions of tricyclic antidepressants (Fig. 6—6). This desensitization may mediate the reduction of side effects of SSRIs as tolerance develops. 

Alan L. Hodgkin (1914—1998) and Andrew F. Huxley (1917- ), both English physiologists, first work out the mechanism of nerve-impulse transmission, showing that a sodium pump system works to carry impulses. 

An important market is for the field magnets in small d.c. motors for which the shape demands high coercivity. Automotive applications for small motors include the windscreen wiper (see Fig. 9.59(a)) and air-blower, window lift, and pumps for fuel, ABS and power-steering. Similar motors are used in washing machines and general kitchen appliances and also for portable tools. Another important application is for stepping motors which convert electrical impulses into incremental mechanical movements for clocks, copying and fax machines and medical equipment. 

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