Boolean searches

The Boolean search operators are used to specify Logical relationships among the terms being searched. 

The Web-based graphical user interface permits a choice from numerous criteria and the performance of rapid searches. This service, based on the chemistry information toolkit CACTVS, provides complex Boolean searches. Flexible substructure searches have also been implemented. Users can conduct 3D pharmacophore queries in up to 25 conformations pre-calculated for each compound. Numerous output formats as well as 2D and 3D visuaHzation options are supplied. It is possible to export search results in various forms and with choices for data contents in the exported files, for structure sets ranging in size from a single compound to the entire database. Additional information and down-loadable files (in various formats) can be obtained from this service. 

Besides subject terms, the CA File also contains bibliographical information, such as author names, location of the laboratory in which the work was done, language of the paper, and so on, and these can be searched. For example, S ROBERTS, J7/AU will find all papers published by any authors named Roberts whose first name begins with J. These terms can be combined with subject terms in Boolean searches. 

A simple spreadsheet, such as Microsoft Excel, can serve as the foundation of a database that has forward and reverse search capabilities. For instance, a table of normal alkanes, together with their densities, boiling points, and melting points, can serve as the starting point. If we want to know all the normal paraffins that boil between 0 and 40 C, all we have to do is to do a sort operation on the boiling-point column and obtain the result that the only paraffin that is in the range is normal heptane with a boiling point of 36.1 °C. For the more advanced Boolean search of normal alkanes that boil between 0 and 40 °C AND melt between —40 and 0 °C, it would be a far more laborious task in a spreadsheet. 

A database such as Microsoft Access would be able to do this Boolean search with ease. The Filter by Form, the Filter by Selection, and the Advanced filter/sort function allow the user to specify density >0.6 AND <0.7 or bp >-40 AND <0. This search yields three results ... 

Substructure and keyword searches including bioactivity, potency and selectivity data, structure-activity relationships, pattern recognition, Boolean searches, and modeling... 

Data import into CDD is currently a simple four-step process from a. csv or. sdf and mapping a dataset to a user-defined protocol if required. Data can be readily mined in CDD and in addition the user can specify which private vaults and public datasets to use (Fig. 2). A full Boolean search is possible by specifying protocol, run, readout, chemical properties, keywords, etc. If molecules are selected, CDD also provides a link to find more information in external databases such as ChemSpider. Data in CDD can also be plotted graphically using an interactive visualization that also provides a snapshot of the molecule and data upon mousing over an X, Tcoordinate. This may allow a simple SAR analysis. 

Fig. 1.2 Number of studies in pheromones in marine invertebrates during the period 1990 and 2009. Results based on Web of Science, Boolean search for pheromon AND taxon freshwater and terrestrial taxa excluded...

When using a "Boolean" search separate all terms by "AND", "OR", or "NOT"... 

Boolean Searches. Boolean algebra is used in information theory. Online queries are input in the form of logical expressions. The operator and is used to narrow a query and or is used to broaden it. The operator not is used to exclude specific words from a query. 

Figure 9 Example of a Boolean search with text fields...

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