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At least 19 recordsLinked to original sources
PubMed1990

Verification of immune response optimality through cybernetic modeling.

An immune response cascade that is T cell independent begins with the stimulation of virgin lymphocytes by antigen to differentiate into large lymphocytes. These immune cells can either replicate themselves or differentiate into plasma cells or memory cells. Plasma cells produce antibody at a specific rate up to two orders of magnitude greater than large lymphocytes. However, plasma cells have short life-spans and cannot replicate. Memory cells produce only surface antibody, but in the event of a subsequent infection by the same antigen, memory cells revert rapidly to large lymphocytes. Immunologic memory is maintained throughout the organism's lifetime. Many immunologists believe that the optimal response strategy calls for large lymphocytes to replicate first, then differentiate into plasma cells and when the antigen has been nearly eliminated, they form memory cells. A mathematical model incorporating the concept of cybernetics has been developed to study the optimality of the immune response. Derived from the matching law of microeconomics, cybernetic variables control the allocation of large lymphocytes to maximize the instantaneous antibody production rate at any time during the response in order to most efficiently inactivate the antigen. A mouse is selected as the model organism and bacteria as the replicating antigen. In addition to verifying the optimal switching strategy, results showing how the immune response is affected by antigen growth rate, initial antigen concentration, and the number of antibodies required to eliminate an antigen are included.

Animals↗
PubMed1990

Mind-body problems in family therapy: contrasting first- and second-order cybernetics approaches.

Using detailed case examples, we contrast first- and second-order cybernetics approaches to family problems involving somatic symptoms in a family member. A second-order cybernetics approach views the reality of the problem as linguistically shaped by those interacting around it, including the therapist and observing team members. This co-constructed reality, the story of the problem, inadvertently contributes to the problem's endurance by narrowing the choice of more effective solutions. In our approach, the therapist elicits from each person his or her story about the illness in the family. The therapist then facilitates a therapeutic conversation that provides a context for new linguistic distinctions to be drawn, including the way mind and body may interact to generate the symptoms. Shifts in beliefs and behaviors follow, and more innovative solutions to the problem can then emerge. Unlike the approach in our previously published work based upon ecosystemic patterns as "system diagnoses," this approach uses only descriptions and explanations of the problem as are collaboratively constructed within this therapeutic conversation.

Adult↗
PubMed1979

The origin of life. A cybernetic and informational process.

According to the model presented in this paper, the beginning of life was marked by the coupling of two complementary nucleotide bases: adenine and thymine. The adenine-thymine system received photons from the sun and stored their energy in the form of a chemical high-energy bond between two phosphoric acid molecules, which were before-hand fixed by adenine from the aqueous environment. The energy of the high-energy bond was then delivered in the form of two waves of electronic excitation. These were utilized to synthesize new molecules, starting from the carbonic acid and ammonia molecules, fixed from the aqueous environment by the polar groups of the nucleotide bases. In this way, a nucleotides-histone protosystem (NHPS) was self-synthesized, evolving step by step towards complexity, by means of some internal cybernetic and informational mechanisms. During its evolution, the NHPS synthesized a limiting membrane, produced the organizing elements of the cellular organelles (chloroplastes, mitochondria, ribosomes etc) and constructed microtubules and microfilaments. Subsequently, the NHPS evolved to the building of DNA-histone system and formed the cellular nucleus.

Adenine↗
PubMed1992

Nursing models in a special hospital: cybernetics, hyperreality and beyond.

Two emerging themes that resulted from research carried out in a special hospital on the use of nursing models are identified. The first theme to emerge was the tendency of the subjects to perceive the models as concrete entities thus undergoing a process of reification. The second theme identified was the adherence to the models outside the contextual nature of the setting which limited their effectiveness. A theoretical framework in which to locate the results of the study is explored using cybernetic learning theory and the notion of hyperreality, using the works of Jean Baudrillard. A method for innovation and changing practice in the special hospital setting is suggested.

Cybernetics↗
PubMed1979

Psychosomatic medicine and cybernetics.

In our daily psychosomatic medicine clinics, we have adopted four principles from Wiener's cybernetics and von Bertalanffy's general system theory. We use the polygraphic method for the diagnosis of psychosomatic disease (black box principle). For the control of psychosomatic symptoms, we use the biofeedback method (feedback principle). We use systematic desensitization to relieve social stresses which cause psychosomatic disease (open and closed system principle). And lastly, transactional analysis, which corresponds to the information and energy principle.

Biofeedback, Psychology↗
PubMed1975

Persecutory delusions: a cybernetic model.

The authors propose a cybernetic model for the formation and maintenance of persecutory delusions. During the formation of persecutory ideation, the threat of loss of control over the self or others interacts with predictions of control from others. This interaction may result in feelings of alien control followed by persecutory explanations. Since the persecutory explanations provide the individual with a new goal of resisting others' influence in order to prevent being controlled, they reduce the threat of loss of self-control. This is how persecutory delusions are maintained.

Cybernetics↗
PubMed1976

Diagnosis of rheumatism by means of universal criteria, obtained by the cybernetic method.

With a view to establishing standardized criteria for the diagnosis of rheumatism suitable for widespread use in polyclinics and in large-scale epidemiological investigations, 3000 adults and children with rheumatism or one of seven similar diseases were subjected to multiple screening in eight centres in the USSR using a specially prepared standard card and standard methods. The information obtained was processed by cybernetic methods. Following determination of the sensitivity, specificity, and informational value of 486 signs of rheumatism, 68 of the most indicative signs were selected as criteria of rheumatism. These were included in the final table and weighted according to their indicational value both individually and in groups as syndromes. Using the table it is possible by simple calculation, without using a computer, to arrive at an objective evaluation of the reliability of the clinical diagnosis of rheumatism in patients with one of a group of eight similar diseases. The final diagnostic table was tested on 562 patients selected epidemiologically or from polyclinics or clinics and was shown to result in a high degree of diagnostic precision (higher than 95%).

Adult↗
PubMed1975

[Hypnosis: logic and cybernetics].

Fundamental notions concerning cybernetics, as derived from the systematic application of logic to questions of communication and control, are illustrated. Particular attention is given to the concepts of "system" "structure" and "dynamics" and it is shown that these concepts ensure that better and more exact understanding and forecasting of reactions in organised beings can be obtained. Turing to hypnosis, it is made clear that a trance is the execution of a momentarily proposed programme; it is not the result of a generalised mechanical action, but is preordained and geared to various situations. The difficulty that the hypnotised subject finds in aciting against his own interests, or against moral priniciples, can be seen, for example, as a consequence of pre-programming. Another result is given moment and a given type of person. Since cybernetis has proved useful in psychology, the hope is expressed that it can be included as a teaching subject for those who learn, practise and teach hypnotism.

Cybernetics↗
PubMedDate not supplied

[A systemic-cybernetic approach to the treatment of psychosis and depression].

An epistemological frame of references wherein activities performed at Servicios de Salud Mental (Mental Health Wards) of La Matanza District (Province of Buenos Aires, Argentina) is discussed. Such frame is systemic-cybernetically oriented, assuming that a therapeut's function deals with triggering a feedback process order so that any disrupted ecology is likely to become self-correctable. It is the author's contention that studies should deepen on how individuals, families--or the system--could be in a position to make their own adjustments. In other words, how could they heal themselves.

Argentina↗
PubMed1990

Neurobiological mechanisms of adaptative plasticity. A possible contribution to cybernetic studies.

Cybernetics can take advantages of future development in the field of Plasticity. The adaptative abilities of the nervous tissue, which is capable to modify its own functional organization and cope with pathological events, are triggered by communication within a network carrying memorized variations in the functional activity of the system induced by external inputs. Plasticity is served by anatomical modifications, as well as by neurophysiological processes. Regeneration, reactive synaptogenesis, functional reorganization, redundancy, equipotentiality are discussed. Some of these mechanisms are still unclear in the human and probably far-fetched. Personal EEG contribution argues against redundancy and equipotentiality.

Animals↗
PubMed1986

The QT-sensitive cybernetic pacemaker: a new role for an old parameter?

A critical review of the available data on QT interval is presented to delineate techniques useful to the development of a QT-sensitive cybernetic pacemaker. The reason for the development of this unit stems from the ability of QT prolongation to predict the onset of life-threatening ventricular arrhythmias in some clinical situations; the QT interval is physiologically related to the cardiac cycle length, therefore providing adequate information to drive both ventricular and atrioventricular sequential rate-responsive pacemakers. This unit might also monitor cardiac rhythm and detect the pathophysiologic precursors of advanced grades of ventricular arrhythmias. A therapeutic role, both pharmacologic and electrical, may also be possible in the future. Integration of these concepts and cooperation between interested physicians, technicians and manufactors will be necessary to produce such a unit at a low cost-benefit ratio. The potential clinical application of this pacemaker deserves attention for the prophylaxis and treatment of sudden arrhythmic death.

Arrhythmias, Cardiac↗
PubMed1976

A cybernetic approach to the origin of the genetic coding mechanism. I. Methodological principles.

It is postulated that some quasi-deterministic code features (universality, connectedness, systematic degeneracy, symmetry, regularity and so on) resulted from unique (and therefore universal) relization of a stochastic evolutionary process. The evolution of real genetic systems should satisfy the principle of succession; that is, loss of a feature that is necessary for a genetic system means death to its carrier. The hypothesis of unique key coincidence is proposed which indicates the mechanisms of arising of the primary correspondence between the linear structures of polynucleotides and polypeptides. If the collinear coincidence was to appear in the key positions of pra-protein with, at least, some of the primitive properties of the pra-amino-acyl-t-RNA-synthetase required for the accelerated recognition of the key positions of pra-template, the positive feed-back mechanism in the system would be most short-circuited so that the repetitive reproduction of pra-synthetase would be much accelerated.

Amino Acyl-tRNA Synthetases↗