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PubMed1984

[General systems theory, a mental frame for geriatric psychiatry].

Though psychogeriatrics is becoming a word of common usage, it is not a word of common meaning. This is a consequence of the lack of a generally accepted theoretical model regarding the complex and multiple pathology of the psychiatric disturbances of older people. On epistemological grounds the author stresses the necessity of a common theoretical concept and as such introduces the General System Theory. The systems approach then shows that the word 'psychogeriatrics' is rooted in a reductionistic concept of man. In order to avoid this the author prefers 'psychiatry of old age' to cover the broad field of the psychiatric disturbances of the elderly.

Aged↗
PubMed1991

Cognitive-developmental systems theory in pervasive developmental disorders.

The concept of reality systems is introduced in context of cognitive-developmental systems theory. Examination of the parallels between the reality systems of normal infants and those of children with pervasive developmental disorders supports the view that the latter are stalled at an early stage of development. Evaluation of pervasively disordered children with closed-system and system-forming disorders indicates the aberrant manner in which such children orient toward and engage objects and events, a manner that precludes flexible adaptation to people or surroundings. Attention is given the role of interruption as it triggers a compensatory reaction to maintain systems and the contribution of such reactions in developing the intentional behavior so lacking in children with pervasive developmental disorders. Finally, the author discusses theory-driven strategies to correct deficits in the body schema, coping with surroundings, social development, and communication and representation.

Child↗
PubMed1980

Systems theory and the anaesthetist.

The application of the various aspects of systems theory has increased steadily over the last 10 years and has proved useful in such diverse fields as surgical services (Spratt et al. 1974), public health (Haas 1974), education (Harrington 1966), nephrology (Bigelow et al. 1973), medical information (Davis 1973), behavior (Shooster 1974), internal medicine (Guyton et al. 1972), metaphysics (Gayer 1972), and sociology (Attinger & Millendorfer 1968). More recently, system analysis has been applied to anaesthetic systems in the engineering literature (Smith & Schwede 1972) and has begun to appear in the anaesthesia literature (Brown 1973). The anaesthetist in the operating room is part of a complex system. In its simplest form the latter involves the anaesthetist, the anaesthesia delivery system, the patient and the surgeon. This discussion is intended to introduce the anaesthetist to some of the terminology and techniques common to the systems analysis approach. Examples have been drawn from biological systems in man which have proved useful to describe in feedback control terms. Where possible, the examples used are those most relevant to anaesthesiology.

Anesthesia↗
PubMed1993

A curriculum based on systems theory.

This paper describes an entry-level curriculum based on systems theory that was designed to promote integrated thinking and a shared image of practice among all of the members of an educational community that included students, faculty, and clinicians. Initiated in 1983, the program integrates occupational therapy theory, critical thinking, and knowledge about person-environmental transactions with traditional medical, biological, psychological, and sociological course work to create a unique educational experience. The curriculum model is based on a spiral learning process that encourages integrated thinking. Furthermore, all concepts are systematically tied to the occupation core, the central theme of the program. Fieldwork is used to reinforce ideas presented in the classroom and features discrete learning experiences where students demonstrate their integration of knowledge and skills. In an evaluation of the program, responses from 78 clinician, 51 alumni, and 132 student questionnaires; feedback from 132 fieldwork supervisors; and longitudinal data from 33 alumni confirmed that graduates are critical thinkers who appreciate the diverse needs of clients while demonstrating an appreciation for the curative effect of meaningful, goal-directed activities.

Curriculum↗
PubMed1995

Comparative characterization of the fermentation pathway of Saccharomyces cerevisiae using biochemical systems theory and metabolic control analysis: model validation and dynamic behavior.

In the first two papers of this series (immediately preceding, this issue), we characterized the steady-state properties of a model of a fermentation pathway in Saccharomyces cerevisiae in four experimental conditions. In each of these conditions, the pictures obtained by metabolic control analysis and biochemical systems theory were coincident, which illustrates the relatedness of the two approaches. In this paper we analyze the quality of this description by means of the tools available within biochemical systems theory, and we show that in some of the experimental conditions studied the system is poorly characterized. The most critical condition corresponds to the immobilization of the cells at pH 5.5, in which the kinetic characterization appears to be inaccurate. Furthermore, sensitivity analysis and the study of the local steady-state stability identify the most critical parameters. The results of these analyses are confirmed by the predictions of the dynamic response of the model using its S-system representation. This illustrates the utility of these tools and warns against using the steady-state characterization without testing its validity.

Fermentation↗
PubMedDate not supplied

The conceptual application of systems theory to stem cell biology: a matter of context.

Much of our current understanding of stem cell biology is derived from reductionist observations made out of context from the functional stem cell compartment. The extrapolation of observations of cellular behavior from highly contrived experimental circumstances to intact biological systems represents an unsupportable assumption on which we currently rely. The conceptual application of systems theory to stem cell biology requires a shift in our view of experimental stem cell science toward the reality of cellular function within a complex biological system. Although the complexity of the system is beyond current mathematical modeling, the conceptual framework of systems theory can provide context to multiple controversies in stem cell biology.

Animals↗
PubMed1990

On the accuracy and reliability of predictions by control-system theory.

In three experiments we used control-system theory (CST) to predict the results of tracking tasks on which people held a handle to keep a cursor even with a target on a computer screen. 10 people completed a total of 104 replications of the task. In each experiment, there were two conditions: in one, only the handle affected the position of the cursor; in the other, a random disturbance also affected the cursor. From a person's performance during Condition 1, we derived constants used in the CST model to predict the results of Condition 2. In two experiments, predictions occurred a few minutes before Condition 2; in one experiment, the delay was 1 yr. During a 1-min. experimental run, the positions of handle and cursor, produced by the person, were each sampled 1800 times, once every 1/30 sec. During a modeling run, the model predicted the positions of the handle and target for each of the 1800 intervals sampled in the experimental run. In 104 replications, the mean correlation between predicted and actual positions of the handle was .996; SD = .002.

Adult↗
PubMed2005

[Social institutions and tempering of affects as "contraints" of social change. Norbert Elias' theory on the civilization theory in light of the biologic system theory of evolution].

This study is to be regarded as a contribution to interdisciplinary research and represents an attempt to clarify the question of whether and to what extent concepts that have been developed in the field of theoretical biology and which have a high degree of importance here can also be applied to sociological phenomena. In particular it is intended to examine the question of whether the civilizing process can be adequately treated using the evolutionary concept of "Constraints". This term, which has only recently been introduced into the discussion by PERE ALBERCH as an evolutionary factor, comprises all of the internal factors which influence the further course of the evolution of a system by ruling out certain possibilities, thus showing a limiting effect. Although "Constraints" go beyond the scope of Darwinian teachings about selection by the environment, they are increasingly accepted today as evolution factors by well-known exponents of Darwinian theory (cf. MAYNARD-SMITH 1985). The increase in popularity of "constraints" is also an expression of the rediscovery of a phenomenon which was originally expressed by RUPERT RIEDL and was introduced by him into German literature in the seventies. In the clarification of this question, special reference is made to the "theory of the civilizing process" by NORBERT ELIAS, since here a highly respected scholar has presented an important sociological theory. Moreover, there is such good scientific access to ELIAS because this author exemplifies his theses in historical terms and thus to a certain extent makes his explanations verifiable in scientific terms. In the treatment of this topic, the central terms and theses of ELIAS will be presented from the considerable scope of his work, and then illustrated with the help of several selected historical case studies. Furthermore, reference will be made at the relevant points to parallels and analogies which the works of ELIAS have to other, predominantly system-theoretical concepts of evolution and which cause it to appear compatible to the latter.

Civilization↗
PubMed1991

[General systems theory, analog models and essential arterial hypertension].

The application of the General System Theory to the fields of biology and particularly of medicine is fraught with many difficulties deriving from the mathematical complexities of application. The authors suggest that these difficulties can be overcome by applying analogical models, thus opening new prospects for the resolution of the manifold problems involved in connection with the study of arterial hypertension.

Humans↗
PubMed2005

Nonlinear system theory: another look at dependence.

Based on the nonlinear system theory, we introduce previously undescribed dependence measures for stationary causal processes. Our physical and predictive dependence measures quantify the degree of dependence of outputs on inputs in physical systems. The proposed dependence measures provide a natural framework for a limit theory for stationary processes. In particular, under conditions with quite simple forms, we present limit theorems for partial sums, empirical processes, and kernel density estimates. The conditions are mild and easily verifiable because they are directly related to the data-generating mechanisms.

Journal Article↗
PubMed1985

A systems theory conceptualization of incest.

In this paper, father-daughter incest is examined from the perspective of general systems theory. Three characteristics of an open system--information exchange with the environment, negentropy, and dynamic homeostasis--are described and examined with respect to the functioning of incestuous families. Two case studies of families with father-daughter incest illustrate the tendency of these families to be more characteristic of the "closed" end of the continuum. The role of the environment in the origin and maintenance of the incestuous symptom is also examined. Implications for treatment are presented within the context of this theoretical perspective.

Adolescent↗
PubMedDate not supplied

Translating a nonlinear systems theory model for homeopathy into empirical tests.

Various investigators have proposed that nonlinear systems theory, notably chaos and complexity theory, provides a heuristically useful modelfor conceptualizing the way in which complementary and alternative medicine therapies, which purport to modify subtle energies, effect change throughout the individual as a whole. In this paper we apply this theory to classical homeopathy and outline an empirical approach for testing the resultant hypotheses. Such research may advance understanding of the mechanisms of homeopathic remedy effects and provide a direction for homeopathic research that expands the previous emphasis on clinical trials and the remedies themselves. In refocusing attention on the dynamics of the patient as a nonlinear complex system, the proposed research program is consistent with the homeopathic emphasis on the individual rather than the disease. This approach may have additional applications that can elucidate similar effects of other energy medicine modalities (eg, acupuncture) on the healing process of the person as a unified whole.

Homeopathy↗
PubMed1980

[The contribution of systems theory and "existential integrative psychotherapy" to the relationship of the concepts "endogenous", "exogenous", "psychogenic", and "sociogenic" in psychic disorders].

Proof is given that the "atomistic" concepts of sickness lead to insolvable contradictions of methodic and logic origin. In this study these contradictions are exemplified and critically analysed, and historical aspects are included. We then propose the dimensions "Interior--Exterior" and "Psychogenous--Somatogeneous" as an heuristic model, dimensions on which any sickness is to be located according to its basic causes. The General System Theory had developed a new formal concept of sickness based on a relatively complete and integral vision of the human being. Nevertheless, the constructs of the General System Theory remain incomplete as they include only objects and their relations, never individual subjects. Wyss however has established explicitely an anthropology of the subject which he connects with his communication orientated concept of sickness. This concept does not judge sickness to be contradictory to health, but both, sickness and health together, form a functional whole on a higher level of abstraction. On this level the organism and its functions, the "interior", represent an inherent component of the "exterior". "Interior" and "exterior"--differentiated in various items--attempt to establish an equilibrium that is always in danger of being desquilibrized.

Communication↗
PubMed1995

Comparative characterization of the fermentation pathway of Saccharomyces cerevisiae using biochemical systems theory and metabolic control analysis: model definition and nomenclature.

Mathematical tools that involve the determination of systemic responses to small changes in metabolites or enzymes have demonstrated their utility for analyzing metabolic pathways. The different methodologies based on these ideas allow for modeling and analyzing biochemical pathways focusing on the coordinate behavior of the whole system. However, one must become familiar with the difference in nomenclature and methodology to relate the models and results obtained by applying these techniques and to appreciate their potential for answering fundamental questions about biochemical systems. In the following three papers we show how this can be facilitated by comparing the nomenclature, methodology, and results of the two leading techniques in this area, metabolic control analysis and biochemical systems theory, using a model of the fermentation pathway in Saccharomyces cerevisiae as a reference system. In the present paper we review the nomenclature, technical concepts, and related experimental measurements while creating a practical dictionary for the reference system that makes the relatedness of the two approaches more apparent. In the second paper, subtitled Steady-State Analysis, we show that both approaches give the same picture for many systemic responses of the reference system. In the third paper of this series, subtitled Model Validation and Dynamic Behavior, we show that the quality of the model can be assessed by studying the sensitivity to changes in the system parameters. We hope to illustrate the usefulness of these tools in providing an interpretation of the experimental measurements in a specific metabolic pathway.

Fermentation↗
PubMed1978

General systems theory: implications for theory and action in occupational therapy.

This paper presents a description of the transformation of science under General Systems Theory, and the relationship of this transformation to the field of occupational therapy. Changes in scientific methods of proof and in scientific laws that underlie theory are discussed. The paper presents a scale for recognizing complexity in phenomena and for analyzing the appropriateness of theories designed to explain the phenomena. It also presents the theory of open systems as an alternative to mechanistic explanations of human behavior.

Models, Theoretical↗
PubMed2006

The application of complex adaptive systems theory to clinical practice in rehabilitation.

It is increasingly emphasised that effective healthcare for the growing number of chronic disease and lifestyle issues must be grounded in a non-reductionist paradigm focused on understanding relationships and applying flexible problem-solving. To address these needs, key principles of complex adaptive systems theory (CAS) are being applied to healthcare planning and research. The aim of this clinical commentary is to provide a brief overview of complex adaptive systems theory and illustrate its relevance to rehabilitation professionals. Further, the review will explore occupational therapist and physiotherapist profession-specific publications for evidence of CAS theory applications that can be used to illustrate the clinical usefulness of complexity science concepts. The commentary will also identify other resources that can assist healthcare providers in developing an understanding of the framework's assumptions and principles for affecting change. Lastly, the implications of failing to acquire a competent understanding of CAS principles and command of the terminology will be addressed and therapists challenged to assume an equal role in mapping healthcare delivery in the 21st century.

Chronic Disease↗
PubMed1989

Metabolic control therapy and biochemical systems theory: different objectives, different assumptions, different results.

The claim by Savageau et al. (1987 a, b, Math. Biosci. 86, 127-145, 147-167) that the theory of metabolic control associated with Kacser & Burns (1973, Symp. Soc. Exp. Biol. 27, 65-104) and with Heinrich & Rapoport (1974, Eur. J. Biochem. 42, 89-102) is no more than a special case of the biochemical systems theory of Savageau and colleagues is examined. It is shown to be based on a misconception of the objectives and assumptions of metabolic control theory. In particular, the control and elasticity coefficients that play a central role in metabolic control theory are not constants and cannot be treated as constants. Consequently they cannot in general be equated with the kinetic orders that appear in biochemical systems theory, though they do correspond at the point where the two theories are tangential to one another.

Animals↗