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PubMed1986

An analysis of migratory systems: 1. Theory.

This is the first of a planned series of three papers in which the authors attempt to combine evolutionary migration models with stochastic utility theory. This first paper deals with the evolution of migratory systems. Such systems are first defined, and the foundations upon which their evolution is based are described. The paper concludes with a discussion of disequilibrium, which is central to the series. "Disequilibrium is related to the concept of a steady state, the existence of which is established for nonlinear migratory systems of the type discussed here."

Demography↗
PubMed1997

Dynamical energy systems and modern physics: fostering the science and spirit of complementary and alternative medicine.

When systems theory is carefully applied to the concept of energy, some novel and far-reaching implications for modern physics and complementary medicine emerge. The heart of systems theory is dynamic interactions: systems do not simply act on systems, they interact with them in complex ways. By definition, systems at any level (e.g., physical, biological, social, ecological) are open to information, energy, and matter to varying degrees, and therefore interact with other systems to varying degrees. We first show how resonance between two tuning forks, a classic demonstration in physics, can be seen to reflect synchronized dynamic interactions over time. We then derive how the dynamic interaction of systems in mutual recurrent feedback relationships naturally create dynamic "memories" for their interactions over time. The mystery of how a photon (or electron) "knows" ahead of time whether to function as a particle or wave in the single slit/double slit quantum physics paradigm is potentially solved when energetic interactions inherent in the experimental system are recognized. The observation that energy decreases with the square of distance is shown not to be immutable when viewed from a dynamical energy systems perspective. Implications for controversial claims in complementary and alternative medicine, such as memory for molecules retained in water (homeopathy), remote diagnosis, and prayer and healing, are considered. A dynamical energy systems framework can facilitate the development of what might be termed "relationship consciousness," which has the potential to nurture both the science and spirit of complementary medicine and might help to create integrated medicine.

Complementary Therapies↗
PubMed2003

Movement systems as dynamical systems: the functional role of variability and its implications for sports medicine.

In recent years, concepts and tools from dynamical systems theory have been successfully applied to the study of movement systems, contradicting traditional views of variability as noise or error. From this perspective, it is apparent that variability in movement systems is omnipresent and unavoidable due to the distinct constraints that shape each individual's behaviour. In this position paper, it is argued that trial-to-trial movement variations within individuals and performance differences observed between individuals may be best interpreted as attempts to exploit the variability that is inherent within and between biological systems. That is, variability in movement systems helps individuals adapt to the unique constraints (personal, task and environmental) impinging on them across different timescales. We examine the implications of these ideas for sports medicine, by: (i) focusing on intra-individual variability in postural control to exemplify within-individual real-time adaptations to changing informational constraints in the performance environment; and (ii) interpreting recent evidence on the role of the angiotensin-converting enzyme gene as a genetic (developmental) constraint on individual differences in physical performance. The implementation of a dynamical systems theoretical interpretation of variability in movement systems signals a need to re-evaluate the ubiquitous influence of the traditional 'medical model' in interpreting motor behaviour and performance constrained by disease or injury to the movement system. Accordingly, there is a need to develop new tools for providing individualised plots of motor behaviour and performance as a function of key constraints. Coordination profiling is proposed as one such alternative approach for interpreting the variability and stability demonstrated by individuals as they attempt to construct functional, goal-directed patterns of motor behaviour during each unique performance. Finally, the relative contribution of genes and training to between-individual performance variation is highlighted, with the conclusion that dynamical systems theory provides an appropriate multidisciplinary theoretical framework to explain their interaction in supporting physical performance.

Adaptation, Physiological↗
PubMed1998

The systemic view of violence: an ethical perspective.

Systems theory has been critiqued by a number of feminist writers who felt that it did not adequately address the issues of violence and male domination in families. This essay argues that systems theory describes the world from an "exogenic" perspective--the scientific world of nature, which is intrinsically amoral. In the exogenic world all causality is circular, as nature maintains a system that has survived for billions of years. Bateson found "mind" to be within the system of nature, implying that mind must also be amoral. However, most people view the world from an "endogenic" perspective, a personal construction of reality molded by the environment in which they live, and which inevitably incorporates morality. Humans believe that violence is wrong, not for intellectual reasons, but for moral reasons. Implications for therapy are presented. A postmodern or constructivist position is taken as a way to acknowledge the influence of relationships on problems and definitions of problems, while allowing for a moral or legal consensus to pervade the therapeutic enterprise.

Causality↗
PubMed1991

The BRIEFER project: using expert systems as theory construction tools.

This article describes the development of BRIEFER I and BRIEFER II, expert systems that advise the therapist on selecting, designing, and developing an intervention at the end of the first therapy session. The process of developing expert systems has aided us in describing what brief therapists do, in modeling the intervention design process, and in training brief therapists.

Clinical Protocols↗
PubMed1982

[Relations of physicalism and vitalism in biology: contribution to the year of Darwin 1982].

With help by an axiom established and some descriptions before this paper, it is possible to model successful processes of growth. In this description, it will be tried to explain in generally form this axiom and to classify it into our scientific system of world. With that comes a dialectical relation between Physicalism and Vitalism. Both continuous and statistical methods are known as possible and necessary forms of description of biological processes. By that the method of Newton can be transferred analogous into Biology with help from the field of information definited before this paper. The developed theoretical conceptions for analysis of growth are conformed also with the demands of system theory by v. Bertalanffy and they will derivated also from his system theory. This work will be finished with firstly ideas for application of this results and with relations of this theory and dialectic.

Biology↗
PubMed1998

Cooperation: the foundation of improvement.

Cooperation--working together to produce mutual benefit or attain a common purpose--is almost inseparable from the quest for improvement. Although the case for cooperation can be made on ethical grounds, neither the motivation for nor the effects of cooperation need to be interpreted solely in terms of altruism. Cooperation can be a shrewd and pragmatic strategy for accomplishing personal goals in an interdependent system. Earlier papers in this series have explored the conceptual roots of modern approaches to improvement, which lie in systems theory. To improve systems, we must usually attend first and foremost to interactions. Among humans, "better interaction" is almost synonymous with "better cooperation." Physicians have ample opportunities and, indeed, an obligation to cooperate with other physicians in the same or different specialties, with nurses and other clinical workers, with administrators, and with patients and families. Many intellectual disciplines have made cooperation an object of study. These include anthropology; social psychology; genetics; biology; mathematics; game theory; linguistics; operations research; economics; and, of course, moral and rational philosophy. Scientifically grounded methods to enhance cooperation include developing a shared purpose; creating an open, safe environment; including all who share a common purpose and encouraging diverse viewpoints; negotiating agreement; and insisting on fairness and equity in the application of rules. These methods apply at the organizational level and at the level of the individual physician. This paper describes the application of these methods at the organizational level and focuses on one especially successful example of system-level cooperation in a care delivery site where interactions matter a great deal: the modern intensive care unit.

Cooperative Behavior↗
PubMed1998

Negotiating reproduction and gender during the fertility decline in Turkey.

This paper is concerned with the cultural construction of reproduction and gender in Turkey as it relates to the remarkable decline from high levels of fertility to near-replacement levels. It critiques demographic transition theory and family systems theory as found in the Turkish demographic discourse. A combination of ethnographic and demographic methodologies are used. The ethnographies are from working-class communities in Istanbul. A concept of negotiated conduct is used to interpret family dynamics in matters of reproductive control replacing the family systems models that are based on the assumption of male domination or patriarchy. It is found that the physical characteristics (male or female) of methods of contraception do not directly reveal whose power dominates negotiations. The variety of experience shows that not only women, but also men, negotiate in favor of birth control or, in some instances, to birth more children. The changes in structural conditions that brought fertility from high levels to near-replacement levels in Turkey were effective without very much "empowerment" of women. The proposition that women's status, in terms of education and economic activity, must improve to bring about a fertility decline is questioned by the Turkish experience.

Anthropology, Cultural↗
PubMed1993

Effectiveness of an intensive partial hospitalization program for treatment of anxiety disorders.

This study evaluates the effectiveness of a partial hospitalization program for the treatment of anxiety disorders. The 5-week program was based on an integration of biological, cognitive, and behavioral theories. Neuman's systems theory provided the framework for the study. The 32 participants were tested pre- and posttreatment. All three hypotheses were supported; "fear of fear," severity of impairment, and general emotional distress were all significantly lower posttreatment than pretreatment. The limitations, including the lack of a comparison group, possible sample bias, and the lack of long-term follow-up, are addressed.

Adolescent↗
PubMed2003

Measurement of heart rate variability by methods based on nonlinear dynamics.

Heart rate (HR) variability has been conventionally analyzed with time and frequency domain methods, which measure the overall magnitude of R-R interval fluctuations around its mean value or the magnitude of fluctuations in some predetermined frequencies. Analysis of HR dynamics by methods based on chaos theory and nonlinear system theory has gained recent interest. This interest is based on observations suggesting that the mechanisms involved in cardiovascular regulation likely interact with each other in a nonlinear way. Furthermore, recent observational studies suggest that some indexes describing nonlinear HR dynamics, such as fractal scaling exponents, may provide more powerful prognostic information than the traditional HR variability indexes. In particular, short-term fractal scaling exponent measured by detrended fluctuation analysis method has been shown to predict fatal cardiovascular events in various populations. Approximate entropy, a nonlinear index of HR dynamics, which describes the complexity of R-R interval behavior, has provided information on the vulnerability to atrial fibrillation. There are many other nonlinear indexes, eg, Lyapunov exponent and correlation dimensions, which also give information on the characteristics of HR dynamics, but their clinical utility is not well established. Although concepts of chaos theory, fractal mathematics, and complexity measures of HR behavior in relation to cardiovascular physiology or various cardiovascular events are still far away from clinical medicine, they are a fruitful area for future research to expand our knowledge concerning the behavior of cardiovascular oscillations in normal healthy conditions as well as in disease states.

Atrial Fibrillation↗
PubMed2003

Stability of serial assessments of motor and communication abilities in typically developing infants--implications for screening.

BACKGROUND: Neuromaturational theory and dynamic systems theory make different assumptions about the rate of development of motor and communication skills. AIMS: The stability of fine motor, gross motor, and communication scores of infants was evaluated to test these assumptions. STUDY DESIGN: This longitudinal descriptive study evaluated infants in their homes at 9, 11, 13, 16, and 21 months of age. PARTICIPANTS: One hundred and two Canadian children of English-speaking parents classified as typically developing at 23 months of age using the Diagnostic Inventory for Screening Children Preschool Screen were included. OUTCOME MEASURES: The Peabody Developmental Motor Scales and the Communication Symbolic Behavior Scales-Developmental Profile were used to assess development at each time. Scores were stable if the 95% confidence intervals around the scores overlapped across all assessments. Correlations evaluated the relationship of scores in a domain over time (normative stability) as well as the relationship of scores between domains (ipsative stability). RESULTS: There was large variability in scores within an infant, among infants and across developmental domains. Typical development is nonlinear rather than occurring at a constant rate. Fine motor, gross motor, and communication skills appear to develop independently. CONCLUSIONS: These results have implications both for developmental screening policies and for early intervention programs. Screening should include multiple domains and multiple time points before referrals are made to early intervention programs.

Age Factors↗
PubMed2002

PACHIQ-R: the Parent-Child Interaction Questionnaire--revised.

The PACHIQ (Parent-Child Interaction Questionnaire) is designed to help clinicians and researchers assess how parents view relationship with their children (PACHIQ-Parent version), and how children evaluate their relationship with their parents (PACHIQ-Child version). The items in this questionnaire refer to both interpersonal behavior and feelings. Conceptually, the PACHIQ is based on learning theory and structural systems theory. The development of the PACHIQ was described by Lange, Blonk and Wiers (1998). The present article reports additional psychometric data obtained in the development and validation of a revised, shorter version of the questionnaire (PACHIQ-R). We present norm tables for families with children who are referred for psychological treatment, and norm tables for families in the normal Dutch population. The PACHIQ-R displays a two-factor structure with factors interpreted as Conflict Resolution and Acceptance. The parent version of the PACHIQ-R contains 21 items, the child version 25 items.

Adolescent↗
PubMed1990

Expectations and outcome skills of a generalist health care administrator.

The question of the degree of technical versus managerial competence to be found in future graduates from health administration programs is not easily resolved. In the HIMSS 1988 survey of CIOs the attributes needed for success are listed in descending rank order as follows: leadership ability, vision/imagination, knowledge of hospital systems, business acumen, decisiveness, and technical competence. CIOs ranked technical competence as less important than other attributes associated with general management success. The expectations for attitudes, knowledge, and skills presented in this article support the greater importance of management abilities relative to pure technical competence. However, it is vital that an appropriate level of technical knowledge and skill be maintained to enable future alumni of health administration programs to function effectively as administrators. Depending on their role in a health care organization, greater or lesser technical knowledge may be needed. Those pursuing a career path toward CIO must, of necessity, have greater technical knowledge and skill. We have discussed necessary and expected attitudes, knowledge, and skills that will be needed by the generalist health administration graduate in the future. It will be important to develop and maintain an attitude that MIS is a strategic tool, that health care technology is a corporate asset, and that information is power. Graduates must recognize the necessity of maintaining and enhancing their knowledge and skills through continuing education. The knowledge base of MIS education should focus on determining information needs to support strategic goals, understanding of general systems theory, principles of systems analysis, design, implementation and maintenance, awareness and exposure to standard application software, and an awareness of external sources of data.(ABSTRACT TRUNCATED AT 250 WORDS)

Computer Literacy↗
PubMedDate not supplied

Fractal and complexity measures of heart rate variability.

Heart rate variability has been analyzed conventionally with time and frequency domain methods, which measure the overall magnitude of RR interval fluctuations around its mean value or the magnitude of fluctuations in some predetermined frequencies. Analysis of heart rate dynamics by methods based on chaos theory and nonlinear system theory has gained recent interest. This interest is based on observations suggesting that the mechanisms involved in cardiovascular regulation likely interact with each other in a nonlinear way. Furthermore, recent observational studies suggest that some indexes describing nonlinear heart rate dynamics, such as fractal scaling exponents, may provide more powerful prognostic information than the traditional heart rate variability indexes. In particular, the short-term fractal scaling exponent measured by the detrended fluctuation analysis method has predicted fatal cardiovascular events in various populations. Approximate entropy, a nonlinear index of heart rate dynamics, that describes the complexity of RR interval behavior, has provided information on the vulnerability to atrial fibrillation. Many other nonlinear indexes, e.g., Lyapunov exponent and correlation dimensions, also give information on the characteristics of heart rate dynamics, but their clinical utility is not well established. Although concepts of chaos theory, fractal mathematics, and complexity measures of heart rate behavior in relation to cardiovascular physiology or various cardiovascular events are still far away from clinical medicine, they are a fruitful area for future research to expand our knowledge concerning the behavior of cardiovascular oscillations in normal healthy conditions as well as in disease states.

Animals↗