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Biomedical subjects

C Spreckelsen

Publications and source records attributed to C Spreckelsen.

3 recordsLinked to original sources

Formalising and acquiring model-based hypertext in medicine: an integrative approach.

Combining a knowledge acquisition methodology with a powerful data model we present an approach to the acquisition, maintenance and browsing of scientific medical hypertext. The hypergraph-based data model supports the consistent treatment of cyclic data structures, the nesting of complex object and provides an elegant way of path declaration to represent time-dependent medical processes or large hypertext tours. It encourages a stepwise schema design and therefore supports a spiral-shaped acquisition process. We formally define view mechanisms on the basis of a rule-based query and modification language. The views enable a context-sensitive presentation of medical knowledge according to the informational needs of the physician. Our approach has been applied to the implementation of an authoring and tutoring environment for a computer-based hypermedia reference book for cerebrovascular diseases (NeuroN). During the acquisition process the expressive power and flexibility of the representational formats have been evaluated.

Artificial Intelligence

Programs, databases, and expert systems for human geneticists--a survey.

We present an overview of the variety of databases and programs that offer substantial aid to medical and molecular geneticists. Databases and expert systems for genetic diseases and birth defects, programs for segregation and linkage analysis, certain DNA and protein sequence databases, and information resources in general for molecular biology are addressed. These systems cannot be used effectively without the newly developed techniques of information exchange based on international computer networks. A short introduction is given to the Internet and to European institutions and organizations that offer help with the acquisition and use of bioinformatic resources.

Computer Communication Networks

Responses of retinal and tectal neurons in non-paralyzed toads Bufo bufo and B. marinus to the real size versus angular size of objects moved at variable distance.

Toads judge the real size of moving visual objects during prey-catching. But neither ganglion cells of the retinotectal projection nor tectal neurons showed a comparable phenomenon in muscle paralyzed toads. In non-paralyzed toads, however, tectal neurons, unlike neurons, displayed a sensitivity to the real size of an object moving at variable distance to the animal. Interestingly, this property was obtained both in monocular T5 smallfield neurons and in most of the investigated T4 widefield neurons.

Animals