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Staff development programs geared toward affective learning goals, such as those related to stimulating cultural sensitivity, require innovative teaching methods. Based on Bowen's family system theory, the author promotes a deeper understanding of the effects of culture on feelings and behavior and presents a cultural circle model of staff development focused on cultural sensitivity.
Metabonomics, a new and rapid-developing technology, will be powerful means to the research of complexed theory system and modernization of traditional Chinese medicine (TCM). Discovery of biomarkers and analysis of common properties from the metabolome of a specific TCM syndrome will facilitate the modernized study of TCM system, promote the quantitative and scientific elucidation of TCM syndrome differentiation, provide an in-depth understanding of the TCM theory of Zang-xiang, help predict the disease on-set, and achieve a comprehensive evaluation of systemic clinical efficacy, safety and mechanism of action of the TCM combination formulas along with a better understanding of intestinal microflora ecology. The new approach with combined metabonomics and TCM methodologies will provide a new pathway and methodology for the study of complicated theory system of TCM and its modernization.
In the first half of the 20th century neo-Kantianism in a broad sense proved itself the main conceptual and methodological background of the central European biology. As such it contributed much to the victory on the typological, idealistic-morphological and psycho-vitalistic interpretations of life. On the other hand it could not give tools to the biologists for working out a strictly darwinian evolution theory. Kant's theory of organism was conceived without evolution as a theory of the internal functionality of the organism. There was only some 'play' with the evolutionary differentiation of the species. Since then the disputes around the work of August Weismann, a synthetical evolution theory which is now behind time, arose. This theory developed from coinciding claims, elaborated by geneticists, mathematicians, and by biologists studying development, natural history and systematics. This was done under a strong influence of marxist ideas. Through the interweaving of such different approaches it was possible for this evolutionary synthesis to influence successfully the development of evolution research during more than 40 years. Philosophically speaking modern evolution theory means therefore an aversion, even a positive abolition of Kantian positions. A number of biologists however--as L. von Bertalanffy--refused to adhere to a misinterpreted Kantian methodology and oriented themselves to an approach via system theory, which obtained a place in evolution research. In fact this is a Kantian approach as well. They only repeated the Kantian dilemma of the evolution which can also be found in Lamarck and Hegel. The system theory of the functionality of the organism never reaches to the level of the evolving species, but remains always on the level of epigenetic thinking, because of its philosophical origin. This paper points out the consequences of this still current dilemma. At the same time an all-enclosing reflection on the methodological, epistemological and the important historical questions of evolutionary biology in its scientific context is recommended.
The role of the family or carer in old age psychiatry is well acknowledged. However, carer interventions are often focused on addressing carer burden alone and are usually individually rather than family based. Interpersonal conflict and family dynamics are rarely addressed. This is not surprising as there is a paucity of literature in family and systems theory applied to the older person, and clinicians are often skeptical about the efficacy of this treatment mode or daunted by the complexity of family and systems theory. Three cases are presented to illustrate the potential benefits of family-based interventions in the setting of commonly encountered clinical situations: (i) the treatment of chronically depressed older people in the community; (ii) the management of behavioral and psychological symptoms of dementia (BPSD) in residential care; and (iii) home-based support and care of the older patient with dementia.
In this article the effects of critical illness on family functioning are described within a systems theory framework. As identified in the literature, family vulnerabilities and strengths that impede or support family functioning during the time a member has a critical illness are discussed. Strategies that nurses can use to assist families of critically ill patients are explored. A challenge to expand family-centered care across various settings is extended.
Dynamic systems theory provides a conceptual framework for the study of change in psychotherapy that is consistent with that used in other sciences. A dynamic systems model of change was proposed and evaluated in the context of cognitive therapy for depression. Consistent with this model, less client protection and more destabilization of depressive patterns predicted more improvement at the end of treatment. Less protection was associated with more therapist support/stabilization. More destabilization was associated with more affective intensity in the session and with more of a therapist focus on the historical antecedents of current problems, exposure to multiple sources of corrective information, and repeated practice of new skills. Although preliminary, this pattern of findings is consistent with the model proposed and with principles of dynamic systems from other sciences.
This is the third in a series of four articles developed for the readers of Coronary Artery Disease. Without language ideas cannot be articulated. What may not be so immediately obvious is that they cannot be formulated either. One of the essential languages of cardiology is mathematics. Unfortunately, medical education does not emphasize, and in fact, often neglects empowering physicians to think mathematically. Reference to statistics, conditional probability, multicompartmental modeling, algebra, calculus and transforms is common but often without provision of genuine conceptual understanding. At the University of Vermont College of Medicine, Professor Bates developed a course designed to address these deficiencies. The course covered mathematical principles pertinent to clinical cardiovascular and pulmonary medicine and research. It focused on fundamental concepts to facilitate formulation and grasp of ideas.This series of four articles was developed to make the material available for a wider audience. The articles will be published sequentially in Coronary Artery Disease. Beginning with fundamental axioms and basic algebraic manipulations they address algebra, function and graph theory, real and complex numbers, calculus and differential equations, mathematical modeling, linear system theory and integral transforms and statistical theory. The principles and concepts they address provide the foundation needed for in-depth study of any of these topics. Perhaps of even more importance, they should empower cardiologists and cardiovascular researchers to utilize the language of mathematics in assessing the phenomena of immediate pertinence to diagnosis, pathophysiology and therapeutics. The presentations are interposed with queries (by Coronary Artery Disease abbreviated as CAD) simulating the nature of interactions that occurred during the course itself. Each article concludes with one or more examples illustrating application of the concepts covered to cardiovascular medicine and biology.
The paper reviews main ideas related to the concept of hierarchy as they are discussed in contemporary general systems theory. After presenting a dictionary definition of the concept, the author examines the intuitive idea of hierarchy quoting Mario Bunge's notion of level structure. Then relationship between two other concepts: a system and a hierarchy is characterised on the bases of Bowler's, Bunge's again, Klir's, and the author's studies. Finally, the paper is concluded that hierarchy is not an otological concept but epistemological one.
In the preceding paper in this issue, we have shown that metabolic control analysis and biochemical systems theory use the same experimental information to describe a metabolic system. In this paper, we analyze the steady-state properties of this pathway by applying both methods. Our results show the correspondence of the steady-state characterizations and illustrate the relationships between the different nomenclatures used. With both approaches, we identify metabolite pools that are strongly influenced by changes in enzyme concentration when cells are immobilized at pH 5.5. In the final paper of this series, which follows, we discuss the need to assess the quality of a model and the potential difficulties that may arise if the steady-state characterization is accepted without testing its quality. We then validate the different models using parameter sensitivity concepts.
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The authority of the therapist is described in reference to a model of the framing of development based on General Systems Theory, as an essential property of the therapist-patient relationship that insures the hierarchical structure of the therapeutic system. The hierarchically superior position of the therapist is based on the relatively great (long term) constancy of his/her functioning mode in therapy, securing the dynamic stability of the therapeutic system. To insure his/her own development (evolution), the therapist himself (herself) needs to be framed by hierarchically superior systems. The importance of the relative autonomy of the therapist in face of the risk of loosing or overdoing his (her) own authority is briefly discussed.
The purpose of this article is to provide an overview of key concepts in understanding complex adaptive systems theory (CAS) and its application to nursing management. CAS concerns altering management practice and revolutionizing how nurse leaders think, behave, and problem solve. CAS discards former beliefs and embraces the concepts of self-organization and attractors (catalysts that allow new behaviors to emerge spontaneously) that enable order and creativity to emerge. Stressing that the most powerful processes begin at the micro level of an organization with the staff, complexity science offers nursing leadership new strategies for successfully navigating chaotic, complex times in health care management.
Psychologists who study children have emphasized family processes that influence children's psychological well-being and subsequent development, but gerontologists have rarely considered the impact of the family as system in adulthood. Drawing on family systems theories, we show how between- family, within-family, and within-individual differences emerge from family interactions in adulthood. Specifically, we consider how adult behavior might be understood in terms of norms sustained by the larger family system. We present three case studies of adult families to illustrate the ways in which their shared beliefs shape emotional experiences, behavior, and conceptions of self and family in adulthood. The family, as a milieu, continues to exert influence over the day-to-day life of individual members after they are grown.
Part 1 presents the signal generation of an ideal pwDoppler system in the time and frequency domain using the means of the one-dimensional system theory. Problems of realisation are ignored, but tissue properties like absorption and scattering are taken into consideration. A comparison is made with pulse echo signals from tissue.
Models of biochemical systems are typically formulated with kinetic data obtained from isolated enzymes studied in vitro, and one has always to question whether or not all the relevant metabolites, processes and regulatory interactions have been identified and whether the parameter values obtained in vitro reflect the actual intracellular environment. In this paper we extend and further test strategies for model assessment and refinement that take advantage of the power-law formalism, which provides the systematic structure underlying biochemical systems theory. Our purpose is three fold. First, we introduce an algorithm for systematically scanning a model for putative errors, which, if corrected, would reconcile its behavior with the experimental system. Second, we further test the working hypothesis that systems in nature are selected to be robust and, hence, that the profile of parameter sensitivities can be used to identify poorly defined regions of a model. Third, we illustrate the use of these strategies within the context of a relatively large and realistic biochemical system--the metabolic pathways of the human red blood cell. Our results show that the reference model we have used is neither locally stable nor robust. The algorithm identifies a number of putative regulatory interactions that, when added to the model, are capable of stabilizing the nominal steady state. We include one of these, the feedback inhibition of hexokinase by fructose-6-phosphate, in a first refinement of the model because there is experimental support for it in the literature. Careful re-examination of the most sensitive section in this model, the pathways of nucleotide metabolism, reveals two mechanisms that were omitted from the reference model: membrane transport of adenosine and inosine, and regulation of phosphoribosyl pyrophosphate synthetase by adenosine diphosphate, 2,3 diphosphoglycerate and 5-phosphoribosyl-1-pyrophosphate. It was also found that the concentration of inorganic phosphate had been inappropriately assumed to be a constant. Modifications to correct these deficiencies produced a second refinement of the model whose parameter sensitivities are reduced on average by 10-fold. Although these refinements are modest and there is substantial room for further improvement, this application identified several biochemically relevant features of the model that had been overlooked. It also points to nucleotide metabolism as the area most in need of further experimental study.
The main factors influencing the microbial stability of chilled prepared food products for which there is an increased consumer interest-are temperature, pH, and water activity. Unlike the pH and the water activity, the temperature may vary extensively throughout the complete production and distribution chain. The shelf life of this kind of foods is usually limited due to spoilage by common microorganisms, and the increased risk for food pathogens. In predicting the shelf life, mathematical models are a powerful tool to increase the insight in the different subprocesses and their interactions. However, the predictive value of the sigmoidal functions reported in the literature to describe a bacterial growth curve as an explicit function of time is only guaranteed at a constant temperature within the temperature range of microbial growth. As a result, they are less appropriate in optimization studies of a whole production and distribution chain. In this paper a more general modeling approach, inspired by system theory concepts, is presented if for instance time varying temperature profiles are to be taken into account. As a case study, we discuss a recently proposed dynamic model to predict microbial growth and inactivation under time varying temperature conditions from a system theory point of view. Further, the validity of this methodology is illustrated with experimental data of Brochothrix thermosphacta and Lactobacillus plantarum. Finally, we propose some possible refinements of this model inspired by experimental results.
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Three hypothetical brain processes--interhemispheric coupling, hemispheric activation, and interhemispheric inhibition--are derived from an equation characterizing general systems theory. To investigate these processes, experimental rats were reared under differing early experience conditions. When adult, they had their right or left neocortex lesioned, had a sham operation, or were left undisturbed. Interhemispheric coupling was measured by means of a correlation coefficient between the right and left hemispheres. The presence of a significant positive correlation is taken as evidence of a negative feedback loop between the hemispheres. In one experimental population, in which rats did not receive any extra stimulation in infancy, the correlation was not significantly different from zero, thus implying that the two hemispheres were operating independently. In another population, in which rats had received handling stimulation in infancy, the correlation coefficient was significant (0.543), indicating that the hemispheres were coupled in a systems arrangement. The processes of hemispheric activation and interhemispheric inhibition were assessed by comparing the mean performance of the two unilateral lesion groups and the group with intact brain. The two rat populations had different forms of brain organizations as measured by these processes. These analyses show that the behavior of the isolated hemisphere cannot be directly extrapolated to the behavior of the connected hemisphere. If there is hemispheric coupling via a negative feedback loop or if there is interhemispheric inhibition, then the disconnected hemisphere may show behaviors that are not evident in the normal connected condition.