Comment on "An early Miocene extinction in pelagic sharks".

Sibert and Rubin (Reports, 4 June 2021, p. 1105) claim to have identified a previously unidentified, major extinction event of open-ocean sharks in the early Miocene. We argue that their interpretations are based on an experimental design that does not account for a considerable rise in the sedimentation rate coinciding with the proposed event, nor for intraspecific variation in denticle morphology.

DentLE. The dental learning environment: a prototype.

The State University of New York at Buffalo School of Dental Medicine was awarded a 'Model Curriculum' grant through the USPHS Bureau of Health Professions Education. The award was provided in support of the School's ongoing effort to design a 'model electronic curriculum' for the health professions. The project's development is described from its grounding in critical thinking and problem solving to a discussion of its features including the organization of its knowledge base, the layout of its computer-based oral health record, and its navigation features.

DentLE. The Dental Learning Environment: a prototype demonstration.

DentLE, the Dental Learning Environment is a hypermedia software system being prototyped as part of a research and development project at the State University of New York at Buffalo School of Dental Medicine. The design seeks to reach beyond single discipline software or cases, and integrate a range of patient problems within a comprehensive dental knowledge base. The approach is to use computer and hypermedia technology to weave together the disciplines of dentistry so that learning occurs in relation to patients, as they appear in the real world. The DentLE system prototype allows the learner to explore information in all the disciplines related to patient problems, as well as other information including "blind alleys" and results of curiosity.