Molecular drive

In what follows, we use simple mean-field theories to predict polymer phase diagrams and then use numerical simulations to study the kinetics of polymer crystallization behaviors and the morphologies of the resulting polymer crystals. More specifically, in the molecular driving forces for the crystallization of statistical copolymers, the distinction of comonomer sequences from monomer sequences can be represented by the absence (presence) of parallel attractions. We also devote considerable attention to the study of the free-energy landscape of single-chain homopolymer crystallites. For readers interested in the computational techniques that we used, we provide a detailed description in the Appendix. ... 

Gonzalez FJ, Nebert DW. Evolution of the P450 gene superfamily animal-plant warfare , molecular drive, and human genetic differences in dmg oxidation. Trends Genet 1990 6 182-186. 

K. Dill, S. Bromberg, Molecular Driving Forces (Garland Science, New York, 2003)... 

Dover underlined that there is no rigid one-to-one relationship between evolutionary mechanisms and environmental processes, but noticed nonetheless that a certain correspondence does exist. He concluded therefore that adaptation is the normal result of natural selection just as exaptation is characteristic of neutral drift, and adoptation is typical of molecular drive. To our purposes, what matters is that we can indeed speak of three mechanisms of evolution the first two are natural selection and neutral drift, while the third mechanism can be called either genomic flux or molecular drive. 

Dover, G. 1982. Molecular drive a cohesive mode of species evolution. Nature, 299,111-117. 

Detection and Quantification of Concerted Evolution and Molecular Drive... 

All the above examples, from the Drosophila rDNA to human repeated sequences, indicate the extent to which a proper detailed analysis of variant repeat distributions that are either in states of transition or are permanently restricted yield important information on the rates, biases, and constraints of the underlying molecular mechanisms, the extent to which they are involved with the activities of one another, and the subtleties of the molecular drive process that underpin concerted evolution. They should discourage both the simplistic view of concerted evolution as an all-or-nothing phenomenon and the naive generalization that the dynamics of genomic turnover operate in the same way, in all species, for all time.13,14... 

Dill, Ken A., and Sarina Bromberg. Molecular Driving Forces Statistical Thermodynamics in Chemistry and Biology. New York Garland Science, 2003. 

Gonzalez, F. J., and Nebcrt, D. W. 1990. Evolution of the P450 genesu perfamily Animal—plant "warfare/ molecular drive and human genetic differences in drug oxidation. Trends Genet. 6 182-186. 

Polymer phase separation and crystallization, as introduced separately in the previous two chapters, have different molecular driving forces that can be simultaneously expressed by the use of the lattice model. Adjusting the corresponding driving forces, the mean-field theory can predict the phase diagrams, and at the meanwhile molecular simulations can demonstrate the complex phase transition behaviors of polymers in the multi-component miscible systems. 

Dill KA, Bromberg S (2002) Molecular driving forces statistical thermodynamics in chemistry biology. Taylor Francis, London... 

The process can be broadly classified as bulk diffusion, Knudsen diffusion, and surface diffusion. The molecular driving force of diffusion is the chemical potential difference created by a local population of a chemical species. Molecules tend to distribute uniformly across the space while migrating among like or unlike molecules. Bulk diffusion is the predominant mechanism when the pressures are high and pore sizes are large. On the other hand, at lower pressures, Knudsen diffusion prevails, when the mean free path of the molecules are larger than the pore size. When the molecules are adsorbed strongly on the pores or the pore sizes are too small, the mechanism of diffusion becomes surface diffusivity. 

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