Structure encoding schemas

One of the most widely used chemical structure-encoding schemas in the pharmaceutical industry is the MDL Connection Table (CT) File Format. Both Molfile and SD File are based on MDL CT File Format to represent chemical structures. A Molfile represents a single chemical structure. An SD File contains one to many records, each of which has a chemical structure and other data that are associated with the structure. MDL Connection Table File Format also supports RG File to describe a single Rgroup query, rxnfile, which contains structural information of a single reaction, RD File, which has one to many records, each of which has a reaction and data associated with the reaction, and lastly, MDL s newly developed XML representation of the above—XD File. The CT File Format definition can be downloaded from the MDL website http //www.mdl.com/downloads/public/ctfile/ctfile.jsp. 

Other structure-encoding schemas are developed by software vendors and academia such as Daylight Smiles, CambridgeSoft ChemDraw Exchange (CDX), and Chemical Markup Language (CML), and they all have advantages and disadvantages. The MDL CT File Format is the only one that is supported by almost all chemical informatics software vendors. 

Stories of these kinds are used to demonstrate that individuals do use prior experience to comprehend stories. However, as evidence of schemas, they are somewhat weak. What we have is confirmation that prior experience is stored in memory and that it influences recall. Studies such as these cannot provide evidence about the structure of the memory storage. Why not We cannot make any such claims because the nature of the storage has not been specified nor have the specific contents. All that we can determine from these studies is that the prior knowledge does influence the subjects as they read and encode the story for later recall. However, these studies have made an important contribution to the overall understanding of schemas by expanding the focus of the research beyond the formal symbolism of the structural rule set to a more general conceptual framework. 

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