Domain stabilization

A frequency domain stability criterion developed by Nyquist (1932) is based upon Cauchy s theorem. If the function F(s) is in fact the characteristic equation of a closed-loop control system, then... 

Wetzel R. Domain stability in immunoglobulin light chain deposition disorders. Adv Protein Chem 1997 50 183-242. 

J.M. Mason, K.M. Arndt, Coiled coil domains Stability, specificity, and biological implications, ChemBioChem 5(2) (2004) 170-176. 

Fig. 22 (a) IR absorption spectra of a bent-shaped twin dimer, (b) Vibrational CD spectra in two chiral domains stabilized by right- and left-CPL [64]... 

Mulhern, T. D., Shaw, G. L., Morton, C. J., Day, A. J., and Campbell, I. D. (1997). The SH2 domain from the tyrosine kinase Fyn in complex with a phosphotyrosyl peptide reveals insights into domain stability and binding specificity. Structure 5, 1313-1323. 

Typical concentrations of dopants (0.05-5 at.%) must result in the formation of dipolar pairs between an appreciable fraction of the dopant ions and the vacancies, e.g. 2La A-VA or 2Fel i+ -V( ). Donor-cation vacancy combinations can be assumed to have a stable orientation so that their initially random state is unaffected by spontaneous polarization or applied fields. Acceptor-oxygen vacancy combinations are likely to be less stable and thermally activated reorientation may take place in the presence of local or applied fields. The dipoles, once oriented in a common direction, will provide a field stabilizing the domain structure. A reduction in permittivity, dielectric and mechanical loss and an increase in the coercive field will result from the inhibition of wall movement. Since the compliance is affected by the elastic movement of 90° walls under stress, it will also be reduced by domain stabilization. 

Donor doping in PZT would be expected to reduce the concentration of oxygen vacancies, leading to a reduction in the concentration of domain-stabilizing defect pairs and so to lower ageing rates. The resulting increase in wall mobility causes the observed increases in permittivity, dielectric losses, elastic compliance and coupling coefficients, and reductions in mechanical Q and coercivity. 

Figure 9.4 Schematic representation of the macromolecular architecture of a large gel-forming respiratory mucin. Two mucin subunits, each about 500 nm in length, are joined end to end via disulfide bonds (S-S) and consist of oligosaccharide-rich regions (represented by the thickened line) and folded domains stabilized by disulfide bonds (represented by the knots). An expanded portion of one of the oligosaccharide-rich regions (not drawn to scale) shows the variety and density of the attached O-linked glycans...

Alpay SP, Roytburd AL (1998) Thermodynamics of polydomain heterostmctures. 111. Domain stability map. J Appl Phys 83 4714... 

The two heavy and two light chains of the immunoglobulin molecule form a tertiary structure resembling the letter Y (Figure 35-7). Disulfide bonds within each of the variable and constant domains stabilize the immunoglobu-... 

In the Fc of IgG [9,23] the two CH3 domains are paired in a pattern similar to that found for the CH1-CL interaction (Fig. 6). The two CH2 domains show no close interaction but have interposed between them two branched N-linked carbohydrate chains which make little contact between one another in human Fc [23] but more extensive contact in rabbit Fc [30]. In the pairing of the CH3 domains, approximately 1000 A2 of surface per domain is involved in the interaction. In the Ch2 case the carbohydrate provides a substitute for the domain-domain contact and helps to stabilise the CH2 domain. However, the CH2-carbohydrate contact area is only about half that of, for example, the CH3-CH3 contact so that one might expect a lower inherent stability for the CH2 domain. Indeed the CH2 domain is more sensitive to proteolytic degradation than the other domains of IgG [24], Domain stability has also been related to the apparent softness of parts of the CH2 domain most remote from the CH2-CH3 interface as indicated by large temperature factors or missing electron density in the crystal analysis of human Fc [23]. A corresponding softness has not, however, been found for rabbit Fc (Sutton B.J., personal communication). Tables 1 and 2 show a comparison of known CH3 and CH2 sequences. 

A serious doubt arises about the phase domain stability of solvent-cast materials. Certainly not all of them (perhaps none ) are in true thermodynamic equilibrium. Yet the difficulty of migration of one block type by diffusion through the A phase of the other, especially at room temperature and below, probably results in a series of pseudoequilibrium states that can maintain their identity for long periods of time. 

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