Stringencies

The stringency of the conditions employed in the unmodified cobalt 0x0 process leads to formation of heavy trimer esters and acetals (2). Although largely supplanted by low pressure ligand-modified rhodium-catalyzed processes, the unmodified cobalt 0x0 process is stiU employed in some instances for propylene to give a low, eg, - 3.3-3.5 1 isomer ratio product mix, and for low reactivity mixed and/or branched-olefin feedstocks, eg, propylene trimers from the polygas reaction, to produce isodecanol plasticizer alcohol. 

MEG 1986 All Buildings Low-rise residential thermal envelope provisions updated to improve stringency. 

The actual state, and absolute amount, of intrinsic energy existing in a body, or system of bodies, are things which lie quite outside the range of pure thermodynamics. This indefiniteness has, however, not the slightest influence on the stringency of the definition, since we can proceed as in the definition of electrostatic potential, and choose any convenient standard state of the body, and use the term intrinsic energy with reference to this standard state. 

Concentration assays are often the least demanding, since usually the component to be measured is abundant and minor components scarce. Even if resolution is poor or there is detector noise, accurate measurements of concentration can still be obtained. In concentration assays, the principal requirements are stringency in the precision of sample dilution and measurement of column losses of the major component. Detector calibration, another important issue in concentration assays, has been discussed above. 

The degree of selection can be adjusted as needed by the use of different vectors or promoters to alter the expression level of the enzyme within the cell. Alternatively, the stringency of selection can be increased by channeling the substrate away by adding a competing pathway [42]. 

Kleeb, A.C., Edalat, M.H., Gamper, M. et al. (2007) Metabohc engineering of a genetic selection system with tunable stringency. Proceedings of the National Academy of Sciences of the United States of America, 104, 13907—13912. 

Pena, S.D.J., Barreto, G., Vago, A.R., de Marco, L., Reinach, F.C., Dias-Neto, E. and Simpson, A.J.G. (1994) Sequence-specific gene signatures can be obtained by PCR with single specific primers at low stringency. Proceedings of the National Academy of Sciences USA 91, 1946-1949. 

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