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Biomedical subjects

E A Vivaldi

Publications and source records attributed to E A Vivaldi.

6 recordsLinked to original sources
PubMed1991

Time course of rat sleep variables assessed by a microcomputer-generated data base.

A microcomputer-based system is described that detects, counts and stores cortical delta and sigma waves, hippocampal theta waves and electromyographic activities in the rat by building matrices with the incidence of those four variables (columns) in 15-second bins (rows). Data tables are submitted to statistical, graphics and spread-sheet software to assess internal organization of sleep episodes and 24-hour distribution of sleep variables. Within sleep episodes, cross-correlograms reveal a delta-sigma-theta sequence, while autocorrelograms quantify clustering and periodicity of variables. Sleep accumulates in the lights-on phase, with high concentration of delta at the beginning of this sleep-predominant phase and of sigma and theta in its second half. These are notable similarities with human sleep architecture. Simple procedures for data reduction into standard behavioral state diagnosis are demonstrated. The low cost of personal computers and data acquisition interfaces facilitates the automation of complex paradigms by ad hoc on-line programs that produce as output a data base that can be processed by standard software, providing a fluid pathway of automated acquisition, analysis and presentation of data.

Animals↗
PubMed1990

[Informatics in the School of Medicine of the University of Chile. I. Origin and evolution of biomedical computing in Chile].

In the sixties and seventies, the School of Medicine of the University of Chile was the first Chilean institution to incorporate computers into academic endeavors through its own Computer Center. Later, professors were marginated from policy making, which became oriented to administrative goals, but they compensated that situation with the easy access to personal computers brought about by present technology. In 1986, when School authorities were again elected by the faculty staff, professors were able to participate again in a committee designing projects in this area. Current development at the School of Medicine include a proliferation of personal computers, the implementation of a computer network with access to medical data bases, and a growing number of applications in the fields of research and teaching. In the near future, due to the accessibility of telecommunications and computers, these advancements should have an impact on the whole biomedical community, a situation that would restore, after many years, the traditional role of the University of Chile in the life of the country.

Chile↗
PubMed1990

[Informatics in the School of Medicine of the University of Chile. II. The school network and access to data bases].

Projects on informatics at the School of Medicine of the University of Chile are being brought about in accordance with both its institutional goals and present trends in technology. Prominent among the latter are the widespread distribution of autonomous processing power represented by low-cost computers and the ease of communication at local and worldwide levels. Our main project has been the design and start of a computer network that integrates the School's Departments and the geographically dispersed teaching hospitals. The principal services provided by the network are local and international electronic mail, access to data bases, and emulation of mainframe terminals (eg, to run remotely a mainframe's statistics software). Automated bibliographic search has been made available both through remote access to Medline data base and through local usage of compact disc (CD-ROM) versions. Since our network is open, it should become a forceful mean of assisting and integrating the biomedical community throughout the country.

CD-ROM↗
PubMed1988

A microcomputer-based sleep system: data acquisition and system calibration programs.

A data acquisition program is described for the Apple II series of microcomputers that allows for continuous, direct monitoring of electrographic elements from cortical, hippocampal and muscle leads from rats. The program detects cortical delta waves and sigma activity, hippocampal theta activity and electromyographic activity. The detected elements are counted and stored in memory at 15 second intervals (bins). Every three hours, the data are transferred to disks for permanent storage and off-line analysis.

Animals↗