G-F transformation

Sawada S, ho T, Hayashi Y, Takahashi S (1992) Fluorescent rotors and their applications to the study of G-F transformation of actin. Anal Biochem 204 110-117... 

Helical growth (HG) occurs when a sequence of linear steps according to MSOA leads to a critical concentration C at which cooperative helical growth begins (Fig. 2b). Because more bonds per unimer are expected in the helical than in the linear chain, the sudden increase of DP at C > C is described by a constant K] > K and by the familiar Zimm-Bragg cooperativity parameter."." The original theory was developed by Oosawa for the nucleus schematized in Fig. lb and applied to the G- -F transformation of actin. A recent extension by van der Schoot and coworkers,"" applied to helical assemblies of discotic molecules, does not require the specification of the critical nucleus. 

Oosawa emphasized the nucleation of the helix with n = 4 that appeared to best describe the experimental data for actin (cf. Section III.B). However, helix nucleation by critical nuclei having n smaller or larger than 4 is also described by Oosawa s theory. Recent work has considered the model with n = 2 for the G F transformation [44] (see also [41]). In fact, the scheme in Figure 7(b) has general validity for a host of nucleation processes in solution including, for instance, the nucleation of spherical micelles and their sphere to rod transition (cf. Section II.A.3) [13]. 

We presented, about 40 years ago, a theoretical framework for understanding the polymerization of protein molecules to helical polymers, based on the study of the G-F transformation of actin, a muscle protein [1-3]. 

Figure 1 The G-F transformation of actin with ATP (open circie), ADP (closed circle), or no nucleotide aclassical scheme. 

In cooperation with many kinds of actin-binding proteins, the G-F transformation of actin generates translational movement of a bacterial cell in a host cell, as in Figure 10 [46], Anchoring and nucleation proteins, depolymerizing proteins, and cross-linking proteins work to make possible a fast cycle of actin molecules from one end of F-actin to the other end, that is, tread-milling. This system has been artificially reconstructed in vitro [47]. 

G-actin, when extracted from a muscle fiber into water, had bound ATP. During polymerization to F-actin, this ATP was hydrolyzed to ADP and inorganic phosphate [7]. The ADP was kept bound in F-Actin. In the process of depolymerization of F-actin to G-actin, rephosphorylation of ADP did not happen. After depolymerization, bound ADP was replaced with ATP in solution. Later it was found that G-actin having ADP instead of ATP also polymerizes to F-actin, although the rate of polymerization is much slower than G-actin having ATP [8]. Even G-actin without ATP or ADP can polymerize, if denaturation of this nucleotide-free G-actin is inhibited by a high concentration of sucrose [9]. The G-F transformation of actin was described by the scheme shown in Fig. 1. 

Voltage polarization depends upon the location of the relay and the location of the fault. It is possible that the residual voltage, at a particular location in the system, is not sufficient to actuate the voltage coil of the directional G/F relay. In such an event, current polarization is used to supplement voltage polarization. Current polarization is possible, provided that a star point is created on the system, even through a A/t> power transformer, if such a transformer is available in the same circuit. Figure 21.20. Else a grounding transformer may be provided as... 

Protection of a domestic or an industrial single phase system Ground fault on an LT system Ground fault protection in hazardous areas. Ground leakage in an HT system Core-balanced current transformers (CBCTs). Ground fault (G/F) protection schemes... 

Daar, I., Paules, R. S and Vande Woude, G. F. (1991). A characterization of cytostatic factor activity from Xenopus eggs and c-mor-transformed cells. J. Cell Biol. 114 329-335. 

Wasserman, W. J., and Masui, Y. (1975). Effect of cycloheximide on a cytoplasmic factor initiating meiotic maturation in Xenopus oocytes. Exp. Cell Res. 91 381-388. Wood, T. G., McGeady, M. L., Blair, D. G., and Vande Woude, G. F. (1983). Long terminal repeat enhancement of -mos transforming activity identification of essential regions. J. Virol. 46 726-736. 

Equation (51)) contains all information about the distribution function G(r) of the decay rates T — Dq2 (Equation (52)). G(F) is obtained from an inverse Laplace transform of Equation (51). The computation of G(T) is a rather difficult task and a short discussion has been given in Section 5.2. 

H. Bakker, G.F. Zhou, H. Yang, Mechanically driven disorder and phase transformations in alloys, Prog. Mater. Sci. 39 (1995) 159-241. 

The relation between the least-squares minimization and the residual density follows from the Fourier convolution theorem (Arfken 1970). It states that the Fourier transform of a convolution is the product of the Fourier transforms of the individual functions F(f g) = F(f)F(g). If G(y) is the Fourier transform of 9(x)-... 

Shogren, R. L., Fanta, G. F., Felker, F. C. (2006). X-ray diffraction study of crystal transformations in spherulitic amylose/lipid complexes from jet-cooked starch. Carbohydrate Polymers, 64, 444 51. 

Solutions of equations and those of extremum problems are closely related. A point is the root of the equations f(x) = only if it minimizes the function g = fTf. Oh the other hand every local extremum point of a differentiable function g satisfies the equations ag(x)/3x = 0. Though a root is not necessarily an extremum point of g, this transformation may be advantageous in one dimension. As will be discussed the situation is, however, completely different with more than one variable. 

Symbols with bar represent the Laplace transform of the variable (e.g. is the Laplace transform of 0). Starred symbols represent a sampled output (e.g. f (t) is the sampled data equivalent of the continuous signal f(0). 

PPh3 behaves differently for M = Ru or Os. In RuCO(P)L, the CO ligand is less firmly bound as in OsCO(P)L. Therefore, the trans-effect of PPh3 suffices to expel the CO ligand in RuCO(P)L (paths a, g, f), but not in OsCO(P)L which can be transformed into OsCO(P) PPh3 (path a). 

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