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Biomedical subjects

Jonathan D Vessey

Publications and source records attributed to Jonathan D Vessey.

4 recordsLinked to original sources

Towards the creation of an international toxicology information centre.

A pilot toxicology database system has been created which is accessible on-line via the world-wide web or in-house via an intranet. It is intended to be suitable as a source of toxicological information and to support structure-activity relationship studies, and it can be searched on chemical structural and substructural as well as toxicological and physico-chemical data. Successful completion of the pilot has led to an ongoing project to develop and expand the system.

Databases as Topic↗

A comprehensive approach to argumentation.

A reasoning model, based on the logic of argumentation, is described. The model represents argumentation as a directed graph in which nodes and arcs can be colored using an ordinal set of weightings and in which the attributes of both nodes and arcs can be modified. It is thus able to deal with the undercutting or augmenting of arguments. Weightings can be propagated through the graph to generate unique weightings for any node or arc. The model is able to deal with contradiction. It can incorporate numerical methods and is able to handle qualitative and quantitative reasoning.

Journal Article↗

Using argumentation for absolute reasoning about the potential toxicity of chemicals.

The application of a new argumentation model is illustrated by reference to DEREK for Windows, a knowledge-based expert system for the prediction of the toxicity of chemicals. Examples demonstrate various aspects of the model such as the undercutting of arguments, the resolution of multiple arguments about the same proposition, and the propagation of arguments along a chain of reasoning.

Algorithms↗

Using absolute and relative reasoning in the prediction of the potential metabolism of xenobiotics.

To be useful, a system which predicts the metabolic fate of a chemical should predict the more likely metabolites rather than every possibility. Reasoning can be used to prioritize biotransformations, but a real biochemical domain is complex and cannot be fully defined in terms of the likelihood of events. This paper describes the combined use of two models for reasoning under uncertainty in a working system, METEOR-one model deals with absolute reasoning and the second with relative reasoning.

Cyclohexanols↗