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PubMedDate not supplied

[Family models and mental anorexia. Part I. Patterns in patient's family origin].

The paper presents family models which associate the development of anorexia nervosa with the specific functioning of the patient's family of origin. The described conceptions are based on systems theory which assumes circular conception of family relations. This allows for avoiding one-sidedness of approach, i.e. perceiving a patient as a victim of the family system. In fact, these models emphasize the patient's part in the specific "game" taking place within the family. The conceptions indicate a number of characteristic patterns of relations between the patient's parents as a married couple as well as between the patient and her parents, which, in the period of adolescence become the source of a crisis that assumes the form of anorexia nervosa. The presented approach, focussed on an analysis of family relations, does not question the importance of other aetiological factors. It only points out that the dynamics of mutual relations within a family is an important mechanism influencing the development of the patient's identification and her psychosexual role as well as the course of the separation/individuation process. These aspects seem pivotal for understanding and treatment of anorexia nervosa.

Anorexia Nervosa↗
PubMed2005

Adaptive chaos: mild disorder may help contain major disease.

We have qualitatively analyzed different cases of human disorders and displacement activities of animals and hypothesize that some of them are examples of low-dimensional dynamical chaos in biological organisms. We also considered a biological organism in the framework of the control system theory and found that chaotic regime in one subsystem may be compensating for the loss of chaos in another subsystem for the sake of stability of the whole system. According to the hypothesis chaotic behavior of different organs sets in a human body as an alternative to serious diseases or even death. The principle of compensation was applied to different physiological systems with chaotic regimes to explain the adaptive nature of chaos there. Implications of the mechanism of adaptive chaos for sleep diseases, e.g., enuresis, and other potentially life threatening disorders of humans, e.g., RLS, are discussed in connection with the possibility to use these ideas for improved treatment strategies. The main conclusion is that adaptive disorders with chaotic symptoms should not be aggressively treated; if adaptive disorders are over treated, the whole organism may be thrown into a more regular state, which eventually will lead to a chronic disease or even death.

Adaptation, Physiological↗
PubMedDate not supplied

A method for analyzing the financial viability of a rural provider-based geriatric clinic.

Little is known about the financial impact of rural provider-based geriatric outpatient clinics on their parent hospitals since the implementation of the outpatient prospective payment system. In this study, systems theory was used to develop a methodology for determining the financial viability of one such clinic in a rural hospital using data commonly found in rural hospital financial systems. Formulas were developed to identify the overall financial viability and a case-study model was utilized to test the formulas; however, this hospital did not track a key data element, resulting in an incomplete analysis.

Aged↗
PubMed2000

A multivariate model of determinants of motor change for children with cerebral palsy.

The purpose of this article is to describe the development of a theory- and data-based model of determinants of motor change for children with cerebral palsy. The dimensions of human functioning proposed by the World Health Organization, general systems theory, theories of human ecology, and a philosophical approach incorporating family-centered care provide the conceptual framework for the model. The model focuses on relationships among child characteristics (eg, primary and secondary impairments, personality), family ecology (eg, dynamics of family function), and health care services (eg, availability, access, intervention options). Clarification of the complex multivariate and interactive relationships among the multiple child and family determinants, using statistical methods such as structural equation modeling, is necessary before determining how physical therapy intervention can optimize motor outcomes of children with cerebral palsy. We propose that the development and testing of multivariate models is also useful in physical therapy research and in the management of complex chronic conditions other than cerebral palsy. Testing of similar models could provide physical therapists with support for: (1) prognostic discussions with clients and their families, (2) establishment of realistic and attainable goals, and (3) interventions to enhance outcomes for individual clients with a variety of prognostic attributes.

Activities of Daily Living↗
PubMed2002

Sepsis research in the next millennium: concentrate on the software rather than the hardware.

Today the basic principles of septic conditions are understood. Nevertheless, sepsis research has reached a critical point. To integrate our knowledge towards a consistent theory of the disease process and to derive effective therapies, new perspectives for future research that fit the complexity of the problem have to be found. We conducted a review of the literature concerning systemic inflammatory response syndrome (SIRS) and sepsis with particular reference to liver pathophysiology. And compared our findings with characteristic features of complex systems. The complexity of sepsis is broadly recognized. A review of the different aspects of liver inflammation during SIRS and sepsis, i.e. endotoxin challenge, cytokine induced dysfunction, the mechanisms of leukocyte transmigration, and hormonal and neuroendocrine regulatory mechanisms is given. Key aspects of complex systems, including parallelism, locality, emergence, and cross-scale interactions are introduced. We conclude that sepsis research needs new perspectives that allow us to handle the complex interactions occurring during the disease process. We propose to focus research on the interactions between the constituents of the system rather than only describing isolated aspects of the disease process. We also conclude that the ideas and techniques of non-linear systems theory are suitable tools for the analysis of complex and dynamic diseases like SIRS and sepsis.

Clinical Trials as Topic↗
PubMed1998

A Cognitive Evaluation of Frame-of-Reference Rater Training: Content and Process Issues.

A multivariate, cognitive evaluation model was used to examine the previously noted effects of frame-of-reference (FOR) training on rating accuracy. The tested model emphasized two content-related issues associated with FOR training: (a) the content of the training itself and the extent that raters agreed with it, which provided an index of the amount of overlap between the theory of performance taught in training and a rater's implicit theory of performance following training; and (b) the content of raters' performance impressions of ratees based on a comprehensive and integrative model of the cognitive representations of persons- Associated Systems Theory (Carlston, 1992, 1994). Undergraduates (N = 172) were trained with FOR or control procedures using two different performance theories, observed and rated videotaped manager performance on three performance dimensions, and engaged in written free-recall of target performance vignettes. A structural model was tested incorporating a latent differential rating accuracy construct. FOR training was associated with higher demonstrated levels of agreement and with changes in ratee representation that were more abstract and more target-referent (i.e., less idiosyncratic) than control training. Agreement was found to be associated with enhanced rating accuracy and more self-referent impressions; however, target-referent impressions were shown to be related to better rating accuracy. Discussion focuses on the interrelated nature of content and process issues in performance appraisal. Using the AST framework, it is also proposed that longstanding manager/subordinate dyads could be expected to benefit the most from FOR training. Copyright 1998 Academic Press.

Journal Article↗
PubMed1998

An analysis of the brain's transfer properties in schizophrenia: amplitude frequency characteristics and evoked potentials during sleep.

BACKGROUND: Classical analysis of spontaneous sleep electroencephalogram (EEG) in schizophrenia commonly reveals alterations of sleep continuity, number of awakenings, slow-wave sleep (SWS), and REM sleep compared to healthy controls; however, conventional analysis cannot help understand dynamic differences of the sleep EEG during different sleep stages. METHODS: We measured late components of auditory evoked potentials (AEPs) and visual evoked potentials (VEPs) during different sleep stages of 11 schizophrenic inpatients and in a sex- and age-matched control group from scalp positions FZ, CZ, and PZ. According to linear system theory, we then computed the amplitude-frequency characteristic (AFC) from averaged AEPs and VEPs in different sleep stages. These AFCs describe the input-output relation of the system under study, leading to a characterization of the transfer properties of the schizophrenic brain during sleep. RESULTS: Significant differences could be found for the transfer properties during stage II and SWS between schizophrenics and controls. During REM a marked enhancement of theta resonance was seen in schizophrenics. CONCLUSIONS: The results of the present study point to highly different central nervous system transfer properties in schizophrenics and controls. Compared to previous investigations in depression, the results provide additional information for distinguishing schizophrenia and depression in EEG studies.

Adult↗
PubMed2006

[Phenomenology and systemic approaches in socio-anthropological studies of illness: a brief critical review].

This paper aims to identify the ways by which the principal frames of reference in the social sciences explain the structure of social actors' knowledge, practices, values, and behaviors regarding health care. The article begins by examining some of the assumptions underlying studies produced within what are called systemic theories. It then proceeds to discuss phenomenological approaches to the health and illness experience. The goal is to clarify how these approaches focus on experience and depart from prevailing systemic models.

Anthropology↗
PubMed1992

New directions in early intervention: P.L. 99-457.

In conclusion, P.L. 99-457 has important implications for professionals who serve hearing-impaired infants and toddlers. The law challenges traditional, child-focused intervention models, and requires professionals to develop programs that are responsive to families' needs. Professionals will need to become familiar with family systems theories, useful family assessment tools, and strategies for collaborative service delivery. Professionals are challenged to determine how enabling relationships can be built with family members. Empowerment of the family system could have far-reaching, positive consequences for the hearing-impaired child.

Child, Preschool↗
PubMed1955

A quantitative electrochemical theory of the electrolyte permeability of mosaic membranes composed of selectively anion-permeable and selectively cation-permeable parts, and its experimental verification. II. A quantitative test of the theory in model systems which do not involve the use of auxiliary electrodes.

The theory of the electrolyte permeability of mosaic membranes composed of ideally anion-selective and ideally cation-selective parts in juxtaposition is tested in a model which consists of an all-electrolytic cyclic arrangement of four component parts: dilute solution/anion-selective membrane/concentrated solution/cation-selective membrane/dilute solution. In this system cations move from the concentrated to the dilute solution across the cation-selective membrane and an equivalent number of anions move through the anion-selective membrane. This movement of ions corresponds to a flow of current in the system. According to the theory, the number of equivalents of electrolyte which penetrate in any given time across the membranes must be identical with the number of faradays of electricity which flow during the same period. The system is essentially a combination of two menbrane-concentration cells arranged in series in a short-circuited state without the presence of electrodes. Experimentally the magnitude of the current was determined by measuring with probe electrodes the potential across an element of the circuit whose resistance was known and constant. The number of faradays of electricity (determined from time-current data) flowing in the system during a measured time was compared with the analytically determined number of equivalents of electrolyte which moved across the membranes during the same period. In a variety of experimental systems the two values show a 1:1 ratio with a mean deviation of +/- 1.8 per cent.

Anions↗
PubMedDate not supplied

[25-year development of the theory of functional systems at P K Anokhin Institute of Normal Physiology and the Department of Normal Physiology of I M Sechenov Moscow Medical Academy].

New trends in the development of the theory of functional systems proposed by P.K. Anokhin in the scientific complex P.K. Anokhin Institute--Department of Normal Physiology during the last twenty five years are regarded. It has been shown that the functional systems represent an objective reality. Holographic and informational properties of the functional systems and general principles of their interrelations in the whole organism i.e. hierarchic domination, multiparametric and successive interaction have been disclosed. Some notions about "systemo-quanta" of vital activity as discrete units of dynamic activity of functional systems have been formulated. Further developments in the systemogenesis of behavioral acts also are presented. New ideas about pacemaker mechanism of dominant biological motivations, the role of oligopeptides in the system organization of behavioral acts have been formulated. The role of early genes in formation of behavioral reactions of animals and in the mechanisms of emotional stress is shown. The role of some oligopeptides in the mechanisms of resistance to emotional stress is stated. Some devices modeling the properties of functional systems and able to assess different organism's functional systems have been developed. Practical application of the theory of functional systems is also shown in the paper.

Academies and Institutes↗
PubMed1999

Anthropological cybernetic model of demographic structures in the Republic of Croatia.

Intentions of the present investigation were: a) to apply a cybernetic model in description of demography of the Republic of Croatia and b) to underline specificity of this type model application in anthrolpology based on definitions of systems theory as a reaction against reductionism. The cybernetic model is based on the idea that continuous processes of childbirth and ageing can be represented by compartment analysis. Compartment subpopulations were subjected to: a) the elimination by mortality and emigration described by constants Fi,0, and b) the enlargement by the immigration process described by constants F0,i. The consistency of the model is evaluated through the comparison between model data and census. The model prediction of the census and mortality for the period between 1953 to 1998 is fair enough (within +/- 2%). Application of this type of models provides a possibility that the anthropological fitness of regions could be quantified. The obtained data reveals that autoreproduction of the system and its fitness could be described by the chaos theory.

Adolescent↗
PubMed1983

A clarification of Multisystem-Multimethod assessment: reductionism versus wholism.

A clarification and response to a critique of the Multisystem-Multimethod (MS-MM) family assessment is provided in this paper. This approach consists of a logic for integrating family assessment, systems thinking, and clinical interventions. In contrast to the wholistic, or systemic, focus of MS-MM family assessment, the critique of these procedures recommends a more reductionistic approach that contradicts basic elements of systems theory. The critique advocates the isolation and measurement of a few family phenomena, whereas MS-MM assessment recognizes the interdependence among the levels of organization and components of family systems.

Adult↗
PubMed1985

Differentiation, individuation, and identity formation: the integration of family system and individual developmental perspectives.

This paper examines the constructs of individuation, differentiation, and identity formation from the individual development and family system theory perspectives. The goal of the paper is to achieve a more thorough understanding of the role of the individuation process in identity formation, and the role of the family system's level of differentiation as a mediator of both these processes. The basic assumption is that both the family system and individual developmental perspectives are interdependent in that the individuation and identity formation process encompass two frames of reference--the individual's efforts toward separation from the family of origin and the impact of these efforts on identity formation and the family system as the social framework within which, and in relation to which, the individuation occurs.

Adolescent↗
PubMed2005

Selection of information resources for education in medical pharmacology.

Pharmacology is the foundation science of medical pharmacotherapy. Education in medical pharmacology (EP) requires the use of information resources (IR) to meet the challenge of the continuous introduction of new drugs and new educational, didactic and pedagogical theories to enhance knowledge. Hence criteria for selecting bibliographic material for EP should be clearly outlined and implemented. In this work we present a method to select IR for EP based on systems theory and focusing on the factors determining: (a) the integration of a list of recommended IR for EP; (b) the design of the acquisition list for faculty and students work; (c) the overall organization of the resources available for its optimal use and benefit in the educational process; and (d) a general strategy for assessing the impact of the bibliographic infrastructure. The proposal is based on information from: (i) lists of recommended readings in the academic program of the Pharmacology course given at the School of Medicine of UNAM in the last 30 years; (ii) the extent of discipline development measured by two indexes derived from the contents of Goodman and Gilman's "Pharmacological Basis of Therapeutics" (G & G); (iii) the number of texts currently found in the collection of FM-UNAM which are classified in the section of Pharmacology using the Library of Congress Classification System (LCCS); and (iv) the comparison of academic versus standardized classification of pharmacology topics, such as Medical Subject Heading (MESH) and LCCS The importance of this proposal relates to its usefulness for EP and for other medical disciplines.

Books↗
PubMedDate not supplied

An approach to single trial analysis of event-related potentials based on signal detection theory.

The aim of the present paper was to introduce a single trial analysis to event-related potential measurement in order to illuminate the mechanisms behind an impaired P300 amplitude occurring under certain experimental conditions. For this purpose we applied tools from linear system theory and signal detection theory to single trials in an oddball paradigm in order to estimate the amplitude of the positive deflection around the P300 latency following target and nontarget stimuli. According to the density functions of these amplitude distributions we operationally defined 'P300 absent in target' (P300 amplitude smaller than an individual threshold under target conditions) as well as 'P300 present in nontarget' (amplitude greater than the threshold under nontarget conditions). Our approach appears to be appropriate to differentiate between an overall reduction of single trial event-related potentials and seldom elicited P300s.

Adult↗
PubMed2002

Modeling the spatial dynamics of regional land use: the CLUE-S model.

Land-use change models are important tools for integrated environmental management. Through scenario analysis they can help to identify near-future critical locations in the face of environmental change. A dynamic, spatially explicit, land-use change model is presented for the regional scale: CLUE-S. The model is specifically developed for the analysis of land use in small regions (e.g., a watershed or province) at a fine spatial resolution. The model structure is based on systems theory to allow the integrated analysis of land-use change in relation to socio-economic and biophysical driving factors. The model explicitly addresses the hierarchical organization of land use systems, spatial connectivity between locations and stability. Stability is incorporated by a set of variables that define the relative elasticity of the actual land-use type to conversion. The user can specify these settings based on expert knowledge or survey data. Two applications of the model in the Philippines and Malaysia are used to illustrate the functioning of the model and its validation.

Agriculture↗
PubMed1998

Space health requirements: the challenges.

This article explores the application of theoretical knowledge to clinical situations based on general systems theory and space health requirements to familiarize health care providers with requirements for the space environment. Preparation for extended periods of humans living in the space environment requires carefully planned delivery system that will promote and maintain health. Past, present, and future efforts for the establishment of'space health delivery systems are discussed. The National Aeronautics and Space Administration (NASA), Man-systems integration standards, NASA-STD-3000 Volume 1-MSIS, Revision B (1995, July), Houston, TX, National Aeronautics and Space Administration documents will be reviewed. Health care services will be supported by the available crew health care and emergency services systems. Providing health care in the extreme space environment with limited resources in which to carry out health practices offers challenges to health care providers.

Aerospace Medicine↗