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PubMed2005

[Theorizing about systems: an ecological task for patient safety research].

As a global safety movement gathers momentum, experts call for a "systems approach" to improve the safety of today's health care environments. Yet, what kinds of systems theories should guide the field of patient safety research? In this paper, it is argued that nurses and other health professionals can use theory and principles from the field of ecological restoration, which is the repair of damaged ecosystems, to study and strengthen the safety of health care environments around the world. When we use restoration science to theorize about health care systems, we develop the ability to think ecologically about our relations with each other and with the environments we share. As we integrate knowledge of restoration science with nurses' knowledge and other knowledge in health care, we may actually create safer health care systems for all at a human and material cost that we are able and willing to pay.

Biomedical Research↗

PubMed2000

The development of intersensory temporal perception: an epigenetic systems/limitations view.

Several theories have stressed the importance of intersensory integration for development but have not identified specific underlying integration mechanisms. The author reviews and synthesizes current knowledge about the development of intersensory temporal perception and offers a theoretical model based on epigenetic systems theory, proposing that responsiveness to 4 basic features of multimodal temporal experience--temporal synchrony, duration, temporal rate, and rhythm--emerges in a sequential, hierarchical fashion. The model postulates that initial developmental limitations make intersensory synchrony the basis for the integration of intersensory temporal relations and that the emergence of responsiveness to the other, increasingly more complex, temporal relations occurs in a hierarchical, sequential fashion by building on the previously acquired intersensory temporal processing skills.

Adult↗

PubMed2003

Local dimension and finite time prediction in spatiotemporal chaotic systems.

We show how a recently introduced statistic [Patil et al., Phys. Rev. Lett. 81, 5878 (2001)] provides a direct relationship between dimension and predictability in spatiotemporal chaotic systems. Regions of low dimension are identified as having high predictability and vice versa. This conclusion is reached by using methods from dynamical systems theory and Bayesian modeling. In this work we emphasize on the consequences for short time forecasting and examine the relevance for factor analysis. Although we concentrate on coupled map lattices and coupled nonlinear oscillators for convenience, any other spatially distributed system could be used instead, such as turbulent fluid flows.

Journal Article↗

PubMed1995

Sequential analysis of the brain's transfer properties during consecutive REM episodes.

Classical analysis of the spontaneous sleep EEG has revealed alterations of REM sleep in psychiatric diseases and under the influence of drugs. In order to elucidate possible functional differences between different REM episodes even in healthy subjects we investigated in 10 volunteers the transfer properties of the brain by measuring auditory (AEP) and visual evoked potentials (VEP) from scalp positions Fz, Cz and Pz during the night. According to linear system theory we computed the so-called amplitude-frequency characteristics (AFC) from averaged AEPs and VEPs during the first and each of the following 3 REM episodes. These functions describe the relationship between the input and output of the investigated system. A 3-factorial analysis of variances with the independent factors frequency band, REM episode and electrode position revealed a statistically significant main effect for the factor REM episode under auditory stimulation (P = 0.05), whereas no significant main effect for REM episode was found under visual stimulation (P = 0.88). Applying a 2-factorial analysis of variance with the independent factors REM episode and electrode position in the case of auditory stimulation we could demonstrate a statistically significant main effect (P = 0.029) for the factor REM episode in the beta range (12.5-20 Hz). A subsequent analysis of contrasts revealed that the first REM episodes could be differentiated from each other. For auditory stimulation the beta resonance during the first REM episode appears enhanced compared to each of the later REM episodes. These findings point to a functional difference of the brain's transfer functions between the first and the 3 following REM episodes, indicating different information processing during consecutive paradoxical sleep.

Acoustic Stimulation↗

PubMed1998

Lumping of whole-body physiologically based pharmacokinetic models.

Lumping is a common pragmatic approach aimed at the reduction of whole-body physiologically based pharmacokinetic (PBPK) model dimensionality and complexity. Incorrect lumping is equivalent to model misspecification with all the negative consequences to the subsequent model implementation. Proper lumping should guarantee that no useful information about the kinetics of the underlying processes is lost. To enforce this guarantee, formal standard lumping procedures and techniques need to be defined and implemented. This study examines the lumping process from a system theory point of view, which provides a formal basis for the derivation of principles and standard procedures of lumping. The lumping principle in PBPK modeling is defined as follows: Only tissues with identical model specification, and occupying identical positions in the system structure should be lumped together at each lumping iteration. In order to lump together parallel tissues, they should have similar or close time constants. In order to lump together serial tissues, they should equilibrate very rapidly with one another. The lumping procedure should include the following stages: (i) tissue specification conversion (when tissues with different model specifications are to be lumped together); (ii) classification of the tissues into classes with significantly different kinetics, according to the basic principle of lumping above; (iii) calculation of the parameters of the lumped compartments; (iv) simulation of the lumped system; (v) lumping of the experimental data; and (vi) verification of the lumped model. The use of the lumping principles and procedures to be adopted is illustrated with an example of a commonly implemented whole-body physiologically based pharmacokinetic model structure to characterize the pharmacokinetics of a homologous series of barbiturates in the rat.

Algorithms↗

PubMed2005

Developmental study of the hippocampal formation in rhesus monkeys (Macaca mulatta): II. Early ablations do not spare the capacity to retrieve conditional object-object associations.

A companion article (see record 2005-06959-001) revealed that hippocampectomy in infancy spares concurrent discrimination learning but not recognition memory. The present report describes the results obtained with a more complex task, conditional object- object association, in which rhesus monkeys (Macaca mulatta) had to first learn to discriminate between pairs of objects rather than single ones and to subsequently remember which particular object had been a member of a rewarded stimulus pair (contextual retrieval). Hippocampectomized infants obtained normal scores in learning individual pair discriminations, but they were severely impaired in contextual retrieval. The results are interpreted in terms of a dual-system theory proposed by R. Hirsh (1974). The results point out not only the importance of age at testing but also the nature of the task. The authors were also able to glimpse possible instances of cooperation or competition between the 2 systems.

Age Factors↗

PubMed1986

Jamaican family structure: the paradox of normalcy.

The relationship between basic research, theory, and clinical work with families is conceptualized during a discussion of Jamaican family structure and the application of change theory to a clinical case of depression in a Jamaican woman. It was found that three types of family structure are prevalent in Jamaica. The European ideal of a patriarchal-patrifocal structure creates problems for working-class Jamaicans. General system theory provides support for a different model. Change theory is applied to resolve the paradox created by the European model.

Adjustment Disorders↗

PubMedDate not supplied

A systems approach to the provision of social work services in health settings: part 2.

In the first part of this presentation published in the last issue, the author offered a sociological view of the hospital as an institution within the economic, political, and value systems of the community. Systems theory is the conceptual base for projecting the potential role of the social worker in the health setting. Part 2, in this issue, deals with impediments and barriers to effective social work in hospitals as well as solution finding based on systems work in combination with direct service skills.

Attitude of Health Personnel↗

PubMed1990

Stability and parameter dependency analysis of a facilitation tectal column (FTC) model.

Mathematical models and computer simulations have been widely used to study the spatio-temporal characteristics of the processing of information carried out by the central nervous system. When trying to show whether or not a neural model accounts for the phenomena under study, if the number of parameters whose values need to be calculated becomes large, then computer simulations alone become very inefficient to define such values. Here, we developed stability and parameter dependency analyses of the mathematical representation of a single facilitation tectal column (FTC) model, to show how by using techniques from non-linear systems theory we can define the ranges of parameter values under which the model would explain the required performance of the neural net model. The benefits of these analyses can be grouped in two parts: first, the advantage of using non-linear systems techniques to analyze, analytically, the dynamics of neural net models; and second, we get a deeper understanding of why the hypotheses embedded in the models yield the appropriate behaviors and what are the critical situations (parametric combinations) under which these behaviors are displayed.

Action Potentials↗

PubMed2006

Unpacking cosmopolitanism for the social sciences: a research agenda.

This article calls for a re-conceptualization of the social sciences by asking for a cosmopolitan turn. The intellectual undertaking of redefining cosmopolitanism is a trans-disciplinary one, which includes geography, anthropology, ethnology, international relations, international law, political philosophy and political theory, and now sociology and social theory. Methodological nationalism, which subsumes society under the nation-state, has until now made this task almost impossible. The alternative, a 'cosmopolitan outlook', is a contested term and project. Cosmopolitanism must not be equalized with the global (or globalization), with 'world system theory' (Wallerstein), with 'world polity' (Meyer and others), or with 'world-society' (Luhmann). All of those concepts presuppose basic dualisms, such as domestic/foreign or national/international, which in reality have become ambiguous. Methodological cosmopolitanism opens up new horizons by demonstrating how we can make the empirical investigation of border crossings and other transnational phenomena possible.

Humanities↗

PubMed1976

Alcohol and drug abuse consultation in the general hospital: a systems approach.

The authors describe a program that is directed at assuring effective treatment and referral for alcoholic and addicted patients in a general hospital; the program was developed to assure maximal utlization of available addiction treatment facilities without adding to the hospital staff. Drawing on systems theory, the authors review both a pragmatic and a conceptual basis for psychiatric intervention with paraprofessional support to provide consultation to the general medical staff who treat alcoholic and addicted patients. They stress the feasibility of altering the nature of the hospital system to achieve more effective treatment for these patients.

Alcoholism↗

PubMed1975

A systems approach to the provision of social work services in health settings: part 1.

This paper , the first of a two-part presentation, offers a socialogical view of the hospital as an institution within the economic, political, and value systems of the community. Systems theory is the conceptual framework for projecting the potential role of the social worker in health setting. Part 2, in the next issue, will deal with impediments and barriers to effective social work in hospitals as well as solution finding based on systems work in combination with direct service skills.

Hospital Administration↗

PubMed2006

[Design of the image browser for PACS image workstation].

The design of PACS image workstation based on DICOM3.0 is introduced in the paper, then the designing method of the PACS image browser based on the control system theory is presented,focusing on two main units:DICOM analyzer and the information mapping transformer.

Data Display↗

PubMed2005

Autism: a window onto the development of the social and the analytic brain.

Although the neurobiological understanding of autism has been increasing exponentially, the diagnosis of autism spectrum conditions still rests entirely on behavioral criteria. Autism is therefore most productively approached using a combination of biological and psychological theory. The triad of behavioral abnormalities in social function, communication, and restricted and repetitive behaviors and interests can be explained psychologically by an impaired capacity for empathizing, or modeling the mental states governing the behavior of people, along with a superior capacity for systemizing, or inferring the rules governing the behavior of objects. This empathizing-systemizing theory explains other psychological models such as impairments of executive function or central coherence, and may have a neurobiological basis in abnormally low activity of brain regions subserving social cognition, along with abnormally high activity of regions subserving lower-level, perceptual processing--a pattern that may result from a skewed balance of local versus long-range functional connectivity.

Attention↗

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↗

PubMedDate not supplied

Using practice genograms to understand and describe practice configurations.

BACKGROUND: Demands for change in medical practices are coming from multiple sources. Since interventions to change clinical practice continue to have limited success, understanding the functional structure of primary care practices and the dynamics of providing care have become increasingly important. METHODS: To portray and understand the primary care office system, we developed "practice genograms" that describe practice participants and their relationships with each other. Formal organizational structure is evaluated using family systems theory and family of origin genogram techniques. RESULTS: Practice genograms provided a more dynamic, relational model than the organizational chart and promoted identification of relationship strengths and weaknesses within a practice the same way that family genograms identify these characteristics in a family system. CONCLUSIONS: Research implications for the use of the practice genogram include enhanced data gathering, increased understanding of the complexity of practices as adaptive systems, and increased understanding of current and potential approaches to changing practices.

Family Practice↗

PubMed1987

Application of non-linear dynamics to the characterization of cardiac electrical instability.

Beat-to-beat alternation in the morphology of the ECG has been previously observed in hearts susceptible to fibrillation. In addition, fibrillation has been characterized by some as a chaotic state. Period doubling phenomena, such as alternation, and the onset of chaos have been connected by non-linear dynamical systems theory. In this paper, we describe the use of a technique from nonlinear dynamics theory, the construction of a first return nap, to assess the susceptibility to fibrillation threshhold in canine experiments.

Animals↗

PubMed2001

Ayurvedic physiology and etiology: Ayurvedo Amritanaam. The doshas and their functioning in terms of contemporary biology and physical chemistry.

The three doshas of Ayurveda and their five respective subdoshas are related to the modern scientific framework of systems theory, phase transitions, and irreversible thermodynamics. These empirically well-established concepts of Ayurveda then appear to be far more general biologic concepts than the neuroendocrinology of their functioning might imply. They express universal concepts applicable across living organisms-control structures governing living systems. The hypothesis that the 15 subdoshas can themselves be considered as 5 triplets implies that on the level of the whole organism, these secondary structures of control appeared at specific stages in the evolution of life, yielding new insights into their development and evolution. The description of varying states of health and disease given in Ayurvedic etiology is related to the format of phase transitions in irreversible thermodynamics.

Energy Metabolism↗