Elasticity regulation

Seih F P, Prewitz M, Werner C and Bomhauser M (2009), Matrix elasticity regulates the secretory profile of human bone marrow-derived multipotent mesenchymal stromal cells (mscs) , Biochem Biophys Res Commun, 389, 663-7. 

Gilbert, P.M., Havenstrite, K.L., Magnusson, K.E., Sacco, A., Leonard , N.A., Kraft, P., Nguyen, N.K., Thrun, S., Lutolf, M.P., Blau, H.M., 2010. Substrate elasticity regulates skeletal muscle stem cell self-renewal in culture. Science 329, 1078—1081. 

Zimmerman, U., Steudle, E. Lelkes, P.I. (1976). Turgor pressure regulation in Valonia utricularis. Effect of cell wall elasticity and auxin. Plant Physiology, 58, 608-13. 

To examine this peculiar behavior, we have converted the elastic compressibility modulus, per unit area, Y (Fig. 12a), to the modulus per chain, Y = F/10 F (Fig. 12b). The elastic compressibility modulus per chain is practically constant, 0.6 0.1 pN/chain, at high densities and jumps to another constant value, 4.4 0.7 pN/chain, when the density decreases below the critical value. The ionization degree, a, of the carboxylic acid determined by FTIR spectroscopy gradually decreases with increasing chain density due to the charge regulation mechanism (also plotted in Fig. 12b). This shows that a does not account for the abrupt change in the elastic compressibihty modulus. 

Even in an ideal situation in which the doctor is a perfect agent for the patient, the need to regulate prices in the pharmaceutical market may arise from insufficient or very weak competition owing to the temporary market power of the manufacturers, the oligopolistic nature of many therapeutic submarkets, low elasticity of demand and imperfect prescriber information.1... 

The influence of RP on selling prices depends on the monopsony power of the buyer, the price elasticity of the product and the cross-price elasticity for substitute products, and also the coverage of products under RP. The situation most likely to result in equivalence between RP and price-cap regulation is when there is a majority buyer, the number of products under RP is very large and demand is very elastic. In general, the RP system attains its objectives best when the pharmaceutical bill has a close relationship with price pressure and when price differentials in the market for equivalent products are high, which has clear links with the presence of generics. 

One of the classical topics of pharmaceutical economics, the price elasticity of demand when there is co-payment or shared financing between the insurer and the user, is addressed by Cruz-Roche20 with some calculations on this elasticity. The same topic is developed by Puig-Junoy,21 applied to the Spanish case. This study includes a review of the international literature with empirical content, a detailed description of co-payment in Spain, its regulation since 1978, the main data and estimates of the effect of the switching of prescriptions from the employed to pensioners, and the price elasticity of demand (which is found to be small). 

In addition to actin and myosin, other proteins are found in the two sets of filaments. Tropomyosin and a complex of three subunits collectively called troponin are present in the thin filaments and play an important role in the regulation of muscle contraction. Although the proteins constituting the M and the Z bands have not been fully characterized, they include a-actinin and desmin as well as the enzyme creatine kinase, together with other proteins. A continuous elastic network of proteins, such as connectin, surround the actin and myosin filaments, providing muscle with a parallel passive elastic element. Actin forms the backbone of the thin filaments [4]. The thin... 

Paul That s probably where I would be coming down. The speed of a smooth muscle is not set by the Ca2+ release. I would maintain that the speed of the muscle is set by its intrinsic unloaded shortening velocity, as modulated by its elasticity and whatever force it is facing. Generally, the Ca2+ transient is largely over before the smooth muscle contracts. I don t believe that the speed of the smooth muscle is regulated by means of Ca2+ waves. 

Many control problems can be better solved with a diaphragm controller. The function of the diaphragm controller (see Fig. 3.27) can be easily derived from that of a diaphragm vacuum gauge the blunt end of a tube or pipe is either closed off by means of an elastic rubber diaphragm (for reference pressure > process pressure) or released (for reference pressure < process pressure) so that in the latter case, a connection is established between the process side and the vacuum pump. This elegant and more or less automatic regulation system has excellent control characteristics (see Fig. 3.28). 

The Elasticity Coefficient Is Related to an Enzyme s Responsiveness to Changes in Metabolite or Regulator Concentrations... 

The elasticity coefficient, e, of an enzyme is an experimentally determined measure of how responsive the enzyme is to changes in the concentration of a metabolite or regulator molecule. 

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