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At least 685 records · Page 38Linked to original sources
PubMed2002

The view from elsewhere: perspectives on ALife modeling.

Many artificial life researchers stress the interdisciplinary character of the field. Against such a backdrop, this report reviews and discusses artificial life, as it is depicted in, and as it interfaces with, adjacent disciplines (in particular, philosophy, biology, and linguistics), and in the light of a specific historical example of interdisciplinary research (namely cybernetics) with which artificial life shares many features. This report grew out of a workshop held at the Sixth European Conference on Artificial Life in Prague and features individual contributions from the workshop's eight speakers, plus a section designed to reflect the debates that took place during the workshop's discussion sessions. The major theme that emerged during these sessions was the identity and status of artificial life as a scientific endeavor.

Cybernetics↗
PubMed1998

Telepresence.

Telepresence, the perception of presence within a physically remote or simulated site, has been identified as a design ideal for synthetic environments. However, confusion exists within the literature about the precise definition of telepresence. Furthermore, there is a need for a plausible and parsimonious model of telepresence. This paper identifies three types of telepresence extant in the literature: simple telepresence, cybernetic telepresence, and experiential telepresence. The third definition is the most interesting. This paper reviews the origins of experiential telepresence and the theoretical approaches commonly used to explain it. One can term these technological approaches, which emphasize the role of control/display technology, and psychological approaches, which identify experiential telepresence with known psychological phenomena. Finally, the paper presents and discusses an integrative approach to telepresence featuring a structured attentional resource model. Actual or potential applications of this research include the design of future human-machine interfaces for teleoperated robots and virtual reality systems.

Cybernetics↗
PubMed1977

Concept and verbal ability as related to the cerebral hemispheres.

A new theory of human brain function is outlined in terms of the cooperative interaction of the cerebral hemispheres. The well-established verbal, symbolic functions of the left hemisphere and the wholistic, spatial functions of the right hemisphere are seen as separate and independent manifestations of the normally integrated verbal-analytic (or "error detector") and conceptual (or "goal state") functions of the left and right, respectively. The relationship between the hemispheres is described in terms of the "goal-directed" system of cybernetics and then compared with related ideas previously presented by Dimond, Penfield, and Piaget.

Aptitude↗
PubMed1998

[Acupuncture: an information therapy?].

Even though modern medicine continues to be governed by the morphological point of view, cybernetics and systems theory are beginning to gain in importance. The concept of "Infomedicine" serves as the basis for a discussion of regulation and the information mechanisms necessary for this to occur. Some of the new insights being made in physics, such as the theory of relativity, quantum physics, and chaos theory provide many valuable explanations. Acupuncture represents a regulation and information therapy, and many parallels can be drawn between traditional Chinese medicine and the discoveries being made in today's physics.

Acupuncture Points↗
PubMedDate not supplied

[The physiology of microcirculation].

Since the work of Harvey and Malpighi, there have been more questions than answers in the physiology of the microcirculation. The microvessels and the interstitial connective tissue form a true functional and structural unit in which the capillary is only a passive feature. It is subject to the constraint of the connective tissue that surrounds it, is only a reflection of the hydraulic conditions above and below it and is a luxury metabolic pathway compared with the importance of the derivative or shortcircuit arteriovenous pathway in which the metarteriole is of major importance. Continual renewal, apparent vasomotor character, and extreme permeability sum up the physiology of the microcirculation. The cybernetics is dominated by the arteriolo-venular functioning and by chain rections. Stasis, the opening of arterio-venous anastomoses, and sludge are the main pathological features. Investigation of capillary function remains difficult under clinical conditions, since different methods give a global picture, that of the vascular-tissue unit.

Capillaries↗
PubMed1975

Criteria of quality and methods of measurement in multichannel biotelemetry.

In contrast with one-channel biotelemetry, multichannel biotelemetry systems permit the analysis of biological systems by means of cybernetics. Some simple examples are given. The basic concept of a multichannel system is described. The criteria of quality of which the nonevident ones are defined by detailing the test circuits are the following (input criteria): number of channels, bandwidth, voltage range, impedance, maximum voltage outside the signal band, stability of the power supply for transducers, factor of safety against multipath propagation, distance between transmitter and receiver, shock, vibration and temperature range, weight, volume and operating time. Output criteria: signal-to-noise ratio, linearity, crosstalk transfer function, different time lags.

Cybernetics↗
PubMedDate not supplied

[Possibilities of myoelectric control of artificial limb prostheses].

This article summarizes the main possibilities for myoelectrical control of prostheses and other rehabilitation devices. In this context fundamental cybernetic aspects, the question of achieving optimal differentiation of antagonistic signals, and 16 possibilities of myoelectrical control, ranging from simple n-state threshold detectors to rate sensitive controllers, to intelligent controllers and pattern recognition techniques, are considered.

Artificial Limbs↗
PubMed1992

Form and process in typology.

With Bateson we want to look for the structure that connects form, process and typology. We do not believe that distinctions are representation of dualism: according to the model proposed by the Second Cybernetics, the distinctions are considered as different sides, that is, an overlap of levels in which one term derives from the other. The logic of the relationship between form and process implies different levels in a self-reference model in which one part is pulled out of the other. At present, speaking about typology, makes sense in order to correlate some complex factors. The first one implies the multidimensionality of intrapsychic and relational reality. The second, a continuous process of self-consciousness of different analytic levels of "reality". The third considers a diagnosis (and typology) as a part of the "information" for the therapist, his patient, his family and his interpersonal context.

Classification↗
PubMed1992

Theoretical considerations on the rehabilitation process.

In the present work some of the theoretical aspects which qualifies the rehabilitation process are pointed out. The context of rehabilitation should include the social network. The isomorphism between the rehabilitation process and the Batesonian concept of mind like "the pattern which connects" is as well emphasized. In this sense the rehabilitation (as the Batesonian mind) is a process imminent in the various contexts the patients deal with and elaborates the differences between these contexts. According to this view it is useful to refer to the Second Cybernetic epistemological model: the structural coupling between therapeutic system, family and social network is the goal of rehabilitation.

Cybernetics↗
PubMed1992

Modus operandi of Planas' appliance.

Planas' approach to the management of a distocclusion, as applied by Simoes, is analyzed physiologically by taking into account the Petrovic-Stutzmann's cybernetic vision of facial growth. This scientifically based theorization further strengthens the clinical validity of this orthodontic ideology and procedure. The clinician, the orthodontist, the functional orthopedist or the functional orthodontist are fundamentally dependent on their knowledge about biophysics, biochemistry and mainly physiology. It is important then that they be acquainted with fundamental concepts of basic sciences as applicable to the specialty. In planning the treatment of a malocclusion, it is necessary to select the appliance or the series of them for sequential use in the correction of a intermaxillary malrelation. It is also useful to be able to predict the response to each appliance. In this case it must be considered the input (appliance in the mouth) designed to produce either displacements of the teeth or other modifications within the dentofacial complex and the output (appliance effect). According to Petrovic and Stutzmann there are 6 tissue level growth categories. Previous investigations using Frankel appliance, LSU Activator, Bionator, Chin Cup and Begg techniques, have shown that when going from the growing category number 1 to number 6 it becomes easier to stimulate the growth rate and amount of the condylar cartilage and of the posterior border of the ramus and it becomes more difficult to restrain their growth rate and amount. In other words we have also to test clinically the effectiveness of the Planas Appliance by taking into account the inter-individual variation in the tissue level responsiveness to it. (Fig. 1-4).(ABSTRACT TRUNCATED AT 250 WORDS)

Activator Appliances↗
PubMed2006

Medical informatics and bioinformatics: integration or evolution through scientific crises?

OBJECTIVES: To contribute a new perspective on recent investigations into the scientific foundations of medical informatics (MI) and bioinformatics (BI). To support efforts that could generate synergies and new research directions. METHODS: MI and BI are compared and contrasted from a philosophy of science perspective. Historical examples from MI and BI are analyzed based on contrasting viewpoints about the evolution of scientific disciplines. RESULTS: Our analysis suggests that the scientific approaches of MI and BI involve different assumptions and foundations, which, together with largely non-overlapping communities of researchers for the two disciplines, have led to different courses of development. We indicate how their respective application domains, medicine, and biology may have contributed to these differences in development. CONCLUSIONS: An analysis from the point of view of the philosophy of science is characteristic of established scientific disciplines. From a Kuhnian perspective, both disciplines may be entering a period of scientific crisis, where their foundations are questioned and where new ideas (or paradigm shifts) and a progressive research programme are needed to advance them scientifically. We discuss research directions and trends both supporting and challenging integration of the subdisciplines of MI and BI into a unified field of biomedical informatics (BMI), centered around the evolution of information cybernetics.

Computational Biology↗
PubMedDate not supplied

On the unfitness of natural selection to explain sexual reproduction, and the difficulties that remain.

In its essence, the explanatory potential of the theory of natural selection is based on the iterative process of random production and variation, and subsequent non-random, directive selection. It is shown that within this explanatory framework, there is no place for the explanation of sexual reproduction. Thus in Darwinistic literature, sexual reproduction - one of nature's most salient characteristics - is often either assumed or ignored, but not explained. This fundamental and challenging gap within a complete naturalistic understanding of living beings calls for the need of a cybernetic account for sexual reproduction, meaning an understanding of the dynamic and creative potential of living beings to continuously and autonomously produce new organisms with unique and specific constellations.

Adaptation, Physiological↗
PubMedDate not supplied

[Regulation of the breadth of the field of self recognition].

On the basis of certain cybernetic considerations, the need is demonstrated of several plasmatic circuits controlling the amplitude of the self recognition field. Regulating every individual circuit in a defense-enhancing direction is demonstrated to trigger a self-destroying, increasing-positive-retroaction mechanism, which is in turn controlled by an increasing-negative-retroactive defense-inhibiting mechanism. The existence is also demonstrated of a correlation between these retroaction processes. When certain stimulation levels are exceeded, such a correlation results in the growth of the negative process being sped up. The possibilities are discussed of stimulating the regulation of the circuit that governs the tumoral defense, keeping the negative retroaction below the limits at which it starts developing exponentially, thereby enhancing anticancer defenses.

Cybernetics↗
PubMedDate not supplied

Mathematical model of the proliferation cycle of lymphoblastic leukemia cells.

In the paper a system of equations is described, which enables computation of the mean number of leukemic cells in the blood as a function of time. After formulation of the problem in the form of cybernetical model, the equations are derived. Then the results of modeling obtained with the aid of a digital computer are described. The paper concludes with short summary.

Cell Cycle↗
PubMed1988

The system of the epidemic process.

An original social-ecological concept of the epidemic process has been constructed on the basis of using social ecology, systemic approach and the basic principles of cybernetics. According to this concept, the epidemic process is regarded as a biosocial, hierarchic, integral system providing for the reproduction of the species of human parasites. At a higher level of organization, the epidemic process is an epidemiological social-ecological system consisting of two interacting subsystems: the biological (epidemiological ecosystem) and the social (social and economic conditions of life of the society) subsystems where the biological subsystem plays the role of the governed object and the social acts as the internal regulator of these interactions. On the basis of this concept a rational structure of the system of epidemiological surveillance over infectious diseases has been proposed according to which each level of the structure of the epidemic process should be subject to adequate monitoring.

Cybernetics↗
PubMed1988

Equilibration and cognition: a review and elaboration of Piaget's genetic epistemology.

Piaget's concept of equilibration--and its current status--has been briefly reviewed. Two fundamental and essentially related issues were identified: the question of conformity between cognitive structures and their referent external reality and, from a cognitive viewpoint, the description of a "growing self-regulatory adaptive system." These issues were reconsidered in relation to, and elaborated on the basis of, relevant ideas mainly from philosophy, cybernetics, and artificial intelligence. A model of a cognitive homeostatic system was developed from an innate subsystem to a learning-based control hierarchy that additionally involves a naturomorphic cognitive subsystem and an abstract cognitive subsystem. The process of equilibration of cognitive structures was approached in terms of the information processing characteristics of these two cognitive subsystems and their inherent sources of error, and the theoretical requirements for ensuring conformity between cognitive structures and their external referents have been indicated. The model, which takes into account these requirements, constitutes a systematic description of a learning based "growing self-regulating adaptive system."

Cognition↗
PubMed1979

Development and organization of the personality as a system of regulation.

Personality is not only the totality of conscious and unconscious characteristics but the unity of somato-organic and psychic characteristics. The somatic organism is a specific morphological and physiological system of the individual. The psyche is a functional structure developing individually in the course of ontogeny, under the effect of internal processing influenced by the environment. A concept is detailed concerning the structure of the human psyche, the system and nature of the conscious and unconscious functions. The personality is a manifestation of the connections and the formation into a system of the somatic organism and the psyche. This interconnection brings about the socialized humanization of the vital processes in man living in society. A concept concerning the essence of personality is discussed, emphasizing the "actual personality" and describing its structure. Clinical examples are given concerning the interconnection of somatic organism and psyche and of the somato-psychic and psycho-somatic processes. Direction and key of the codes as well as the importance of the meaning of life within the cybernetic system is explained, and conclusions are drawn for the purposes of education.

Child↗
PubMed1980

[Towards the end of Kraepelin era?].

The kraepelinian conception which still prevails in contemporary psychiatry no longer allows us to express all the diversity of observed mental disorders. Moreover, some classical resistances and innovations had foreshadowed the necessity of its renewal. Nowadays the quantitative studies using statistics and the computer, as well as the application of scientific theories to the qualitative aspect of disorders have until now failed in improving the situation. However the theory of communication, cybernetic, the general system theory have shown the possibility of seeing mental disorders as dysfunction of systems. Likewise a new method of operatory observation has permitted to result in an integrated system of permanently open functional models. Moreover the transformations of the disorders among some patients lead to evoke the abstract notion of psychopathologic continuum. The latter allows to view mental pathology, no longer as syndromes and entities, but as functional disorders of a same psychodynamic whole. Consequently, the disorders are the evidence of dysregulations of various mental organizations and the result of a dysfunction in the integration of the latter. Their expression in terms of integrated functional models better shows their diversity, polymorphism, and mobility. What is at stake in such a debate is not only theoretic but also practical and therapeutical.

Adult↗