Discrimination ratio

Figure 1.23 Discrimination ratios for the enantiomers propranolol, BINAP and Naproxen over DMB PSG imprinted silica (black bars) and PSG reference material (grey bars). (Reproduced from ref. 49, with permission).

Ligand substitution kinetics on water-soluble porphyrins have been measured.18,105 106 The Co111 ion of the porphyrin exchanges axial ligands several orders of magnitude more readily than do simple amine or aqua complexes. Relatively low ligand discrimination ratios and positive activation entropies support a dissociative mechanism (equation 18, Table 7). 

Sensitivity (change in response per unit concentration change) Decay constant (radioactivity) or discrimination ratio... 

Lin, T.-H. and Tsai, K-C. (2003) Implementing the Fisher s discriminant ratio in fe-means clustering algorithm for feature selection and data set trimming. /. Chem. Inf. Comput. Sci., 44, 76-87. 

Some investigators have expressed the activities of the two aminotransferases as a ratio (AST ALT) to assist with interpretation. However, it is necessary for each laboratory to establish its own discriminating ratios because the use of different methods and animal species affects the values obtained for these ratios. From the factors affecting these measurements in different species, it can be seen that ratios established for one species cannot be used for another species. 

Kinetic parameters for R, capsulata (for photosynthetically grown cells) and the KmS and 7maxS for E. coli are from previously published reports (10,12,36), The Kis for R, capsulata are kinetically determined values from experimente such as Reference 36, The ratios for the E, coli i stems are not accurately determined Kt values but rather calculated discrimination ratios of Reference 12,... 

The trace-scavenging Kdp system (which is responsible for accumulating K in/K out gradients of greater than 10 1 Reference JO, 12) has a discrimination ratio (KVRb ) of 1000, while the major TrkA system (which functions under conditions of abundant extracellular has a ratio of only 10. The high aflSnity Kdp system includes a transport ATPase (11,37), which is in fact the first example of a cation-specific transport ATPase in bacteria. Very recently, Epstein and Laimins (JO) have reevaluated transport in E. colt and concluded that there are two, rather than four, separate transport systems for The two deleted transport systems were actually the TrkA system with mutationally altered kinetic parameters. 

Fisher s Discriminant Ratio in a k-Means Clustering Algorithm for Feature Selection and Data Set Trimming. 

As the final step, discriminant analysis was used. The discriminant ratio was 90.8% (79/87). Only 2 individuals of TypeL was discriminated as Typel, whereas only 3 individuals of TypeL were discriminated incorrectly as Type Teak individuals can be thus classified into three types (Typel, TypeT, and TypeL) on the basis of the contents of quinone constituent (isodeoxylapachol and tectoquinone) and also their distribution corresponding to variations in the contents. For more comprehensive investigations, the subsequent works should be conducted with larger samples including plantation teak trees from East Java as well as from community forests that scattered in the island of Java... 

The apparently high discrimination ratio for the 18-mer site at 55 C and 500 nM target concentration is an artefact of the high bulk fluorescent background and low surface signals encountered under these conditions. 

Eo/kT Discrimination ratio (A) with (B) without molecular anvil molecular anvil A/B... 

It is clear from the Table that discrimination ratio with molecular anvil is very high. To make clear the effect of the molecular anvil, discrimination ratios without molecular anvil are shown together for comparison. 

It is clear that improvement of discrimination ratio by molecular anvil goes up as the value of binding energy increases. As for the values of Eo it can be derived from heats of vaporization. Eo is nearly equal to AH 2/z where AH is the value of heat of vaporization and z is the number of nearest neighbours and is between 6 and 12. For heat of vaporization of about 10 K cal. the value of Eo/kT is about 3. For amino acid there is no data of heat of vaporization, but their lattice energy values are of similar order or more, an order of discrimination factor of L-and D-isomer may be explained by this model. 

The molecular anvil model of enz3mie is proposed and it can explain consistently the two distinct features of enzyme, high catalytic power and high specificity. By employing this model discrimination ratios for optical isomer were calculated for various values of binding energy. It is shown that the molecular anvil plays an important role in elevating discrimination factor. 

Allaway, W.G., Osmond, C.B., Troughton,J.H. Environmental regulation of growth, photosynthetic pathway and carbon isotope discrimination ratio in plants capable of Crassulacean acid metabolism. Proc. Int. Conf. Mechanisms of Regulation of Plant Growth. Bull. R. Soc. N.Z. 12,195-202 (1974b)... 

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