Library design diversity sampling

Cell-based fraction and cell-based density have consistently provided the most satisfactory results in our earlier work (15). The main difference between these two cell-based metrics relates to diversity and representativeness. Whereas cell-based fraction is designed to sample the complete library with... 

The issues of evolutionary library design in the frame of material and catalyst discovery were described. Concepts of diversity management on material library to enhance the efficiency of the optimisation were proposed. The diversity monitoring is implemented via two different approaches. The first deals with a dynamic monitoring of mutation and crossover rates, whereas the second involves a selection step based on sample distance . Simulations of optimisation were performed on a surface response, which was designed to mimic realistic data. Algorithm performances were compared in terms of both efficiency and reUability. 

Chemoinformatics (or cheminformatics) deals with the storage, retrieval, and analysis of chemical and biological data. Specifically, it involves the development and application of software systems for the management of combinatorial chemical projects, rational design of chemical libraries, and analysis of the obtained chemical and biological data. The major research topics of chemoinformatics involve QSAR and diversity analysis. The researchers should address several important issues. First, chemical structures should be characterized by calculable molecular descriptors that provide quantitative representation of chemical structures. Second, special measures should be developed on the basis of these descriptors in order to quantify structural similarities between pairs of molecules. Finally, adequate computational methods should be established for the efficient sampling of the huge combinatorial structural space of chemical libraries. 

The diverse combinatorial screening described in the previous sections revealed active Pt-Ru-Co methanol oxidation catalysts, especially near Pt20Co6oRu2o. A second primary screening cycle (Fig. 11.8) focused on a more limited compositional space to isolate the active region in more detail. Figs. 11.15 and 11.16 show the design and the sampled compositional space of a Pt-Ru-Co ternary library. The design contains a pure Pt catalyst, Pt-Co binaries (row A), Pt-Ru binaries (column 1)... 

A primary, or unbiased, library is a large set of compounds (t5q)ically thousands to millions) based on diversity and aimed at the discovery of samples of interest for targets for which little, if any, information is available. Diversity is a concept unrelated to the library size that attempts to evaluate the representation of chemical space by a chemical library using computational methods If this space is sampled evenly by the components of a library, then this library is considered to be diversity based (Fig. 4.1, left). A focused, or biased, library is a similarity-based set of compounds (typically hundreds to thousands) aimed at the discovery and optimization of lead structures for a target for which a structural model on which to design the hbrary is available. Similarity is a concept unrelated to the library size that is opposite to diversity if the library components are clustered around the model structure A, the library is similarity based (see Fig. 4.1, right). 

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