Sequential state assignment

When this model is synthesized, three flip-flops are inferred two to hold the value of the machine state (MooreState) and one for the output Z. States are encoded using sequential state assignment. 

A. Bdckmann, A. Lange, A. Galinier, S. Luca, N. Giraud, M. Juy, H. Heise, R. Monstserret, F. Penin and M. Baldus, Solid-state NMR sequential resonance assignments and conformational analysis of the 2 X 10.4 kDa dimeric form of the Bactillus subtilus protein Crh. J. Biomol. NMR, 2003, 27, 323-339. 

In Fig. 4 we compare the timings for three different models, the simple one K per processor, the wrapped algorithm, and a model where two states are assigned per processor sequentially. Note that until J = 50 the one K per processor model job uses the smallest amount of wall clock time. It is clear, however, that this method does not make efficient use of computer resources. The wrapped model, however, scales very well and outperforms the sequential two K per processor model at every / > 0, a clear illustration of the degradation of performance due to load imbalance. 

As a result of static disorder, often alternate positions of atoms can be resolved in electron density maps. In macromolecular crystals, some of the flexible regions possess variable conformers and as a consequence none of the individual ones can be detected in electron density maps. Thus, dynamics between several energetically similar states and/or larger amplitude makes to vanish more mobile sequential subunits. In practice, more than two or three conformer makes detection and/ or assignment impossible. In other words lower than 25-33% of relative population of conformers is unseen by diffraction methods. 

Solid-state NMR also can be applied to membrane proteins in lipid bilayers, and recent advancements in magic angle spinning solid-state NMR show promise for stmcture determination. Although the stmctures of small crystalline proteins (89) and membrane bound peptides (90) have been determined, the stmcture of a polytopic membrane protein has yet to be reported. The major necessity that is required to push the technique forward is the de novo sequential chemical shift assignment of the amino acid residues, and in the last few years, several groups have reported successful strategies (91, 92). 

The electron affinities of the alkyl and cycloalkyl halides reported in the NIST tables are tabulated and evaluated in Appendix II. The NIST value is returned by a sequential search, using CX, CC1F, or CHX. In some cases two values that differ by more than the uncertainty have been reported so excited-state values can be assigned. Many of the Ea have only been measured by one technique thus, the experimental values could refer to an excited state. 

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