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Biomedical subjects

V Tagliasco

Publications and source records attributed to V Tagliasco.

At least 19 recordsLinked to original sources
PubMed1993

Confocal microscopy and cellular bioinformatics.

An exhaustive description of most biological data requires, besides a set of analytic information, an eidetic representation of the data itself. In this paper, two topics are presented. The first one is confocal microscopy, an advanced technique to produce multidimensional cellular and subcellular structures images. The second one is a software application, named BIOCELL, based on a relational database management system, developed to provide the biologist with an integrated tool to handle simultaneously cell biology linguistic and eidetic information.

Biotechnology↗
PubMed1982

A model of the early stages of the human visual system: functional and topological transformations performed in the peripheral visual field.

A model of the early stages of the visual system is presented, with particular reference to the region of the visual field outside the fovea and to the class of retinal and lateral geniculate nucleus cells which are most active in the processing of patter information (X-cells). The main neuroanatomical and neurophysiological properties taken into account are: the linear increase of the receptive fields diameter with eccentricity, the constancy of the overlap factor and the topological transformation operated upon the retinal image by the retino-cortical connection. The type of filtering taking place between the retina and the visual cortex is analyzed and some simulations are presented. It is shown that such a filtering is of a bandpass space variant type, with center frequencies that decrease from the center (i.e. the fovea) toward the periphery of the visual field. This processing is "form invariant" under linear scaling of the input. Moreover, considering the properties of the retino-cortical connection, it is shown that the "cortical images" undergo simple shifts whenever the retinal images are scaled or rotated.

Humans↗
PubMed1980

Anthropomorphic robotics. I. Representing mechanical complexity.

A study of the fundamental principles upon which manipulation dexterity is based cannot help mixing robotic and neurophysiological concepts. A preliminary step in this study consists of trying to understand the complexity of manipulation dynamics. Though complexity shows itself in the massive number of elements of kinematic and dynamic equations, the fundamental simplicity of the underlying mechanical laws suggests to look for a structure, particularly from the computational point of view. Accordingly, a working computational model is proposed that organizes the massive computational load into a structure which is composed of a small number of computational units and lends itself to parallel computation.

Arm↗
PubMed1980

Anthropomorphic robotics. II. Analysis of manipulator dynamics and the output motor impedance.

An important factor in trying to capture the complexity of many manipulation problems is the notion of Output Motor Impedance, i.e., the relationship between a set of disturbing forces and the resulting variation in arm configuration. The functional significance of such force/displacement characteristics is investigated, showing how several aspects of different manipulation tasks (holding against gravity, inserting, fast moving, and throwing) can be naturally described in terms of appropriate modulation of the impedance characteristics of the manipulator. For this reason, impedance modulation can be considered an integral part of motor control.

Arm↗
PubMed1977

The use of mini- and micro-computers in eye clinical practice.

In an ophthalmological department there are many sectors in which the use of computers can give useful support. We have singled out three major areas of interest: 1. the rationalization of the flow of patients; 2. the management of clinical records; 3. the automatization of ophthalmological devices. Instead of using different dedicated computational systems we preferred to focus our attention on a unique system based on a minicomputer driving several parallel micro-processors. Preliminary results are given.

Computers↗
PubMed1977

The visual field examination and its automation.

An automated system for examination of the visual fields is described. The entire campimetric examination was simulated in order to enable an in-depth analysis of actual examinations. The program runs on a HP2100 computer with a 16K core. The main advantages of the system are: greater speed, less patient fatigue, greater reliability, repeatability and accuracy.

Diagnosis, Computer-Assisted↗
PubMed1977

[Problems of automated perimetry (author's transl)].

The choice of the most convenient computer, the strategies for stimulus presentation, the fixation control, the presentation of results and the response objectivation are the main problems of automated perimetry, some of which are already solved, others are likely to be solved in the near future. The authors present their experiences on automation of perimetry and indicate future perspectives of this procedure.

Computers↗
PubMed1975

Preliminary results about a new remotely controlled projection campimeter.

A newly remotely controlled projection campimeter is described. The instrument can be remotely controlled either automatically by a minicomputer or manually by an operator. The introduction of the computer allows the elimination of the systematic errors due to the operator. Moreover, the campimeter is enabled to choose the optimal strategy for target presentations. The last task of the computer consists in the memorization of the graphical results, their comparison and their quantification.

Automation↗
PubMed1972

Auditory evoked response: meaningfulness of stimuli and interhemispheric asymmetry.

Interhemispheric asymmetries of different magnitudes were observed in human cortical auditory evoked responses to speech and sound-effect stimuli. The wave with peak asymmetry occurred 100 milliseconds after signal onset. The amount of asymmetry of the amplitude of this wave was related to the meaningfulness to the subject of the auditory stimulus rather than to the mere use of verbal versus nonverbal materials.

Adult↗