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PubMed2005

Monitoring of trophic chains.

In the paper simple trophic chains of the type resource-producer-primary consumer are considered. For an analysis of the dynamic state monitoring of this system, the concept of observability of mathematical systems theory is proposed. Using a linearization method of non-linear observation systems, biologically interpretable sufficient conditions are obtained to guarantee local observability. The latter means that based on the dynamic observation of a single component, the state of the whole system can be uniquely recovered, at least near a positive equilibrium.

Algorithms↗

PubMed2004

Inner control as an operational mechanism in attention deficit hyperactivity disorder.

Understanding children with attention deficit hyperactivity disorder (ADHD) through a systems theory perspective creates a view of these children as having developed ineffective systems and strategies for acting upon the world. It is proposed that just as a child must develop a system of inner control to become a proficient and independent reader, this same system is necessary for effectively controlling the problematic behaviors associated with ADHD. Speech-language pathologists (SLPs) can encourage the development of this inner control by providing services that foster meaning-based literacy and that enhance visual perception and processing strategies. As SLPs and educators seek to establish and employ embedded literacy activities, they will more effectively meet the needs of their students identified with ADHD.

Attention Deficit Disorder with Hyperactivity↗

PubMed1992

Physical illness and the family emotional system: psoriasis as a model.

Most physical illnesses are characterized by significant variability in age of onset and severity of clinical course. Although many diseases may occur in the context of a strong family history for the disease, they may also occur when there is no such history. Psoriasis has been chosen as a model for demonstrating that variability in age of onset, clinical course, and family history for a given disease may be explained, in part, by factors related to the family emotional system, a concept described by family systems theory (Bowen theory). Links between the clinical manifestations of psoriasis and the family emotional system have important treatment implications.

Adaptation, Psychological↗

PubMed1999

Living with HIV/AIDS: the voices of HIV-positive mothers

The study reported here was undertaken to investigate the experiences of HIV-positive mothers with the system of services designed to help them, how they cope with the infection, particularly as it relates to parenting, and their concerns, preferences and plans for the future care of their children. A focus group method was selected because it is well suited for this type of exploratory research. A total of 40 HIV-positive mothers participated in six different focus groups. The issues that emerged from the data analysis revealed that, using systems theory, they could be logically classified by the type or level of system in which the issue was primarily located. The three system levels were (1) individual and family, (2) organizations and providers, (3) policy and community. Within each of these categories, issues could be further delineated by whether they provided women with resources or presented them with additional stress. Conclusions and recommendations for providers are made based on the systems framework that gave structure to the results.

Journal Article↗

PubMed2003

The conceptual basis of mathematics in cardiology: (I) algebra, functions and graphs.

This is the first in a series of four articles developed for the readers of. 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.

Cardiology↗

PubMed2003

The conceptual basis of mathematics in cardiology: (II). Calculus and differential equations.

This is the second 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.

Cardiology↗

PubMed2003

The conceptual basis of mathematics in cardiology IV: statistics and model fitting.

This is the fourth 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.

Cardiology↗

PubMed1988

Symbiosis, the family, and natural systems.

Family systems theory, as developed by Murray Bowen, has its conceptual basis in natural systems. A basic premise is that emotional process is not unique to homo sapiens and that human behavior might better be understood by observing this process in the broader context of all natural systems. This essay discusses the phenomenon of symbiosis as it is used in the natural sciences and as it relates to the emergence of increasingly complex systems in nature. Finally, the emergence of the parent/offspring symbiosis from its possible origins to its development in the human family is discussed.

Dependency, Psychological↗

PubMed1992

Nursing process approach improves receivables management.

The "nursing process" is a systematic decision-making approach to problem solving based on open-system theory. This theory assumes that there is an on-going interchange between all system components. Components cannot be viewed in isolation, because decisions regarding one component will affect other components. Receivables management is similar to the nursing process, in that it involves constant diagnosis, assessment, and intervention in the work in process during all phases of the receivables cycle. In experiments that applied the nursing process concept to the management of accounts receivable in several hospitals, gross days in accounts receivable were reduced and cash flow was increased.

Accounts Payable and Receivable↗

PubMed1993

[Clinical decisions in a philosophical perspective].

Medicine is both a scientific and a humanistic discipline. The foundation for clinical decisions has four components (two scientific and two humanistic). 1) The biological component (reasoning based on biological theory). Biological thinking is currently being revolutionised, partly through the development of systems theory. 2) The empirical component (reasoning based on experience from earlier patients), which comprises both uncontrolled and controlled experience. 3) The empathic-hermeneutic component (reasoning based on an understanding of the patient as a fellow human being). Empathy requires hermeneutic knowledge which can be acquired through personal experience and by qualitative research. 4) The ethical component which comprises both utilitarian and deontological considerations.

Clinical Competence↗

PubMed1998

Family of origin and current relationship influences on codependency.

This study investigated codependency in Caucasian individuals within the framework of Bowen's Family Systems Theory. The sample consisted of a group of couples, in which one member of the couple was a recovering alcoholic in an aftercare program, and a group of matched, comparison couples. Participants completed a demographic questionnaire, the Friel Codependency Assessment Inventory, and the Personal Authority in the Family System (PAFS) Questionnaire. The findings confirmed that codependency levels were higher in clinical than in comparison couples. Moreover, within the clinical group, there was little difference between alcoholics and their spouses with respect to dysfunction in their families of origin, current families, or their codependency levels. The findings further suggested that the etiology and function of codependency are different in clinical and nonclinical families. In the clinical sample, the family of origin and current relationship characteristics were related to codependency in patterns consistent with previous theory and research. For the nonclinical sample, however, the findings contradicted conventional codependency theory. The findings suggest that, in contrast to clinical populations, codependency in nonclinical populations has some links with favorable characteristics of family functioning.

Adult↗

PubMedDate not supplied

A systems approach in nursing administration: structure, process, and outcome.

This article presents a systems approach for administrators to consider as they review structure, process, and outcome in their healthcare organization. Systems provide a way to access data, information, and knowledge. Systems organize and unify the complex world of nursing practice in healthcare systems. Use of King's conceptual system, Theory of Goal Attainment, and transaction process is presented as an example that helps the multiple individuals and groups use information and knowledge to structure nursing practice. The transaction process helps individuals and groups identify goals and outcomes that lead to effective nursing care, evidence-based practice, and cost-effectiveness.

Communication↗

PubMed1986

Theory of psychiatric treatment systems. An approach.

A theory of psychiatric treatment systems may be approached using stochastic probability models. Theory construction proceeds in six stages corresponding to broad assumptions about the causal relationships among variables affecting the life course and treatment encounters of members of a target population. The theory is progressively refined to describe short-term life changes, longer-term life-course modifiers, predictors of treatment utilization, treatment system policies, and treatment effects. The ultimate aim is to forecast the effects of policy change.

Health Policy↗

PubMed1995

Clinical supervision: a three-way mirror.

The principles and process of a model of clinical supervision for psychotherapy are presented and described through two cases. The model draws heavily from Bowen's family systems theory and Peplau's theory of interpersonal relations. The relationships in the client-family, client-therapist, and therapist-supervisor systems mirror each other, and changes in self-definition, and in the management of anxiety of persons in one system catalyzes changes in parallel systems. Two cases illustrate the model. In the first case, anxiety needed to be raised to levels optimal for learning. In the second case, no learning occurred until levels of anxiety were reduced.

Anxiety↗

PubMed2002

Exploring the limits of spatial resolution in radiation dose delivery.

Flexibility and complexity in patient treatment due to advances in radiotherapy techniques necessitates a simple method for evaluating spatial resolution capabilities of the dose delivery device. Our purpose in this investigation is to evaluate a model that describes the ability of a radiation therapy device to deliver a desired dose distribution. The model is based on linear systems theory and is analogous to methods used to describe resolution degradation in imaging systems. A qualitative analysis of spatial resolution degradation using the model is presented in the spatial and spatial frequency domains. The ability of the model to predict the effects of geometric dose conformity to treatment volumes is evaluated by varying multileaf collimator leaf width and magnitude of dose spreading. Dose distributions for three clinical treatment shapes, circular shapes of varying diameter and one intensity modulated shape are used in the evaluation. We show that the model accurately predicts the dependence of dose conformity on these parameters. The spatial resolution capabilities of different radiation therapy devices can be quantified using the model, providing a simple method for comparing different treatment machine characteristics. Also, as different treatment sites have different resolution requirements this model may be used to tailor machine characteristics to the specific site.

Brain↗

PubMed1986

Thomas-Fermi theory for atomic systems.

The classical Thomas-Fermi theory of the electrons in an atom is amended in a manner that produces continuity of the electron density rho. This is done by imposing the constraint that e(-2kr) [unk](2) rho dr should be finite, with k determined by the nuclear cusp condition, followed or preceded by an optimum coordinate scaling. Electron densities and total energies are shown to be vastly improved.

Journal Article↗

PubMed2006

A fuzzy discrete event system approach to determining optimal HIV/AIDS treatment regimens.

Treatment decision-making is complex and involves many factors. A systematic decision-making and optimization technology capable of handling variations and uncertainties of patient characteristics and physician's subjectivity is currently unavailable. We recently developed a novel general-purpose fuzzy discrete event systems theory for optimal decision-making. We now apply it to develop an innovative system for medical treatment, specifically for the first round of highly active antiretroviral therapy of human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) patients involving three historically widely used regimens. The objective is to develop such a system whose regimen choice for any given patient will exactly match expert AIDS physician's selection to produce the (anticipated) optimal treatment outcome. Our regimen selection system consists of a treatment objectives classifier, fuzzy finite state machine models for treatment regimens, and a genetic-algorithm-based optimizer. The optimizer enables the system to either emulate an individual doctor's decision-making or generate a regimen that simultaneously satisfies diverse treatment preferences of multiple physicians to the maximum extent. We used the optimizer to automatically learn the values of 26 parameters of the models. The learning was based on the consensus of AIDS specialists A and B on this project, whose exact agreement was only 35%. The performance of the resulting models was first assessed. We then carried out a retrospective study of the entire system using all the qualifying patients treated in our institution's AIDS Clinical Center in 2001. A total of 35 patients were treated by 13 specialists using the regimens (four and eight patients were treated by specialists A and B, respectively). We compared the actually prescribed regimens with those selected by the system using the same available information. The overall exact agreement was 82.9% (29 out of 35), with the exact agreement with specialists A and B both at 100%. The exact agreement for the remaining 11 physicians not involved in the system training was 73.9% (17 out of 23), an impressive result given the fact that expert opinion can be quite divergent for treatment decisions of such complexity. Our specialists also carefully examined the six mismatched cases and deemed that the system actually chose a more appropriate regimen for four of them. In the other two cases, either would be reasonable choices. Our approach has the capabilities of generalizing, learning, and representing knowledge even in the face of weak consensus, and being readily upgradeable to new medical knowledge. These are practically important features to medical applications in general, and HIV/AIDS treatment in particular, as national HIV/AIDS treatment guidelines are modified several times per year.

Anti-HIV Agents↗

PubMed1976

[Towards effective treatment in child psychiatry].

The author suggests that psychoanalytic theory, developmental theories and family dynamics theories are insufficient to allow for a comprehensive treatment of children. Adding elements of Systems Theory, he proposes that in every case, individual, familial and ecological factors be devised to solve problems in each area. He illustrates the approach with the clinical report of a successfully treated case of vitiligo.

Child↗