Comparison of the ultrafast to slow time scale dynamics of three liquid crystals in the isotropic phase

2002 ◽  
Vol 116 (14) ◽  
pp. 6339-6347 ◽  
Author(s):  
S. D. Gottke ◽  
Hu Cang ◽  
Biman Bagchi ◽  
M. D. Fayer
Genetics ◽  
2000 ◽  
Vol 154 (3) ◽  
pp. 1403-1417 ◽  
Author(s):  
David J Cutler

Abstract Rates of molecular evolution at some protein-encoding loci are more irregular than expected under a simple neutral model of molecular evolution. This pattern of excessive irregularity in protein substitutions is often called the “overdispersed molecular clock” and is characterized by an index of dispersion, R(T) > 1. Assuming infinite sites, no recombination model of the gene R(T) is given for a general stationary model of molecular evolution. R(T) is shown to be affected by only three things: fluctuations that occur on a very slow time scale, advantageous or deleterious mutations, and interactions between mutations. In the absence of interactions, advantageous mutations are shown to lower R(T); deleterious mutations are shown to raise it. Previously described models for the overdispersed molecular clock are analyzed in terms of this work as are a few very simple new models. A model of deleterious mutations is shown to be sufficient to explain the observed values of R(T). Our current best estimates of R(T) suggest that either most mutations are deleterious or some key population parameter changes on a very slow time scale. No other interpretations seem plausible. Finally, a comment is made on how R(T) might be used to distinguish selective sweeps from background selection.


2007 ◽  
Vol 40 (7) ◽  
pp. 1629-1634 ◽  
Author(s):  
Jonathan B. Dingwell ◽  
Domenic F. Napolitano ◽  
David Chelidze

1992 ◽  
Vol 194 (3) ◽  
pp. 213-216 ◽  
Author(s):  
John J. Stankus ◽  
Renato Torre ◽  
C.D. Marshall ◽  
S.R. Greenfield ◽  
A. Sengupta ◽  
...  

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