Selective and predictable

Germolec, D.R., Selectivity and predictivity in immunotoxicity testing Immune endpoints and disease resistance, Toxicol. Letters, 149, 109, 2004. 

It has been found that isotactic polypropylene produced by unbridged biscyclopen-tadienyl zirconium catalysts is formed through a mixed chain end control and enan-tiomorphic control.352 Molecular mechanics calculations led to the development of a model that takes into account nonbonded interactions to rationalize observed selectivities and predict properties of new catalyst systems.353... 

Fortunately, the rules of chemical reactivity and conformational analysis, coupled with the laws of thermodynamics, join forces to allow us to functionalize polyhydroxy aldehydes and ketones (aldoses and alduloses) in a selective and predictable fashion. 

Although palladium-catalyzed processes have also achieved improvements in the field of acetylenic coupling [2], the Glaser-Hay and Cadiot-Chodkiewicz copper-mediated methods still remain the most used. Further mechanistic investigations seem to be necessary, to overcome the limitations of the existing procedures, mainly poor selectivity and predictability. 

Berger, J. O. and Pericchi, L. R. (1996). The intrinsic Bayes factor for model selection and prediction. Journal of the American Statistical Association, 91, 109-122. 

The symmetry of the crystal is indicated in its diffraction pattern. Systematic absences in the diffraction pattern show that there are translational symmetry elements relating components in the unit cell. The translational component of the symmetry elements causes selective and predictable destructive interference to occur when the specific translation in the arrangement of atoms are simple fractions of the normal lattice... 

The internal symmetry of the crystal is revealed in the symmetry of the Bragg reflection intensities, as discussed in Chapter 4. The crystal system is derived by examining the symmetry among various classes of reflections. Key patterns in the diffraction intensities indicate the presence of specific symmetry operations and lead to a determination of the space group. The translational component of the symmetry elements, as in glide planes or screw axes, causes selective and predictable destructive interference to occur. These are the systematic absences that characterize these symmetry elements, described in Chapter 4. 

Scheme 44 Selective and predictable functionalization at various positions of substrates with multiple C-H bonds.

In view of the selectivity and predictability of both the cleavage reaction of the cation radical and the addition of benzyl radicals to the anion radical, this process can be considered a useful method for aromatic alkylation, although, as it appears from the foregoing discussion, it is limited to arene polynitriles. Provided that the thermodynamic requirements for the various steps are met, chemical yields are often satisfactory since, as... 

We have made use of the cation-selective properties of macrocycles to design liquid membrane [6], supported liquid membrane [6], and macrocycle-bonded silica gel [7] systems for specific cation separations. The selective transport of Ag [8, 9], Pb " [8], K" [10] and Li [11] was observed in a bulk liquid membrane system using various macrocyclic ligands. In the supported liquid membrane (thin sheet and hollow fiber) systems, selective and predicted separations of Na /K , Cd " / Hg ", and others have been achieved [12, 13],... 

M. Ozdemir, Evolutionary Computing for Feature Selection and Predictive Data Mining. Ph.D. dissertation, Rensselaer Polytechnic Institute, Troy, New York, 2002. 

It is noteworthy that in the course of this sequence both carbon atoms of the double bond become substituted in a highly selective and predictable manner. 

The Edman procedure allows for the ready sequencing of only relatively short polypeptides. For longer ones (e.g., those with more than 50 residues), it is necessary to cleave the larger chains into shorter fragments in a selective and predictable manner. These cleavage methods rely mostly on hydrolytic enzymes. For example, trypsin, a digestive enzyme of intestinal liquids, cleaves polypeptides only at the carboxy end of arginine and lysine. 

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