The Major Elements of the Systems Approach

Purpose This study aims to contribute to the understanding of how elements of the socioecological system shape individual behaviors. The problem of childhood overweight and obesity is analyzed as existing within a complex system of relationships at different levels by means of system dynamics (SD). Design/methodology/approach Secondary sources and primary information collected from an elementary school were used to analyze the influences of several social environmental factors on the dietary habits and physical activity of children. The major elements that influence these behaviors were identified via a socioecological framework (SEF), and the interrelationships among these elements were described using an SD model. Then, several scenarios corresponding to social marketing actions oriented toward modifying the influence of specific elements in the socioecological system were proposed to evaluate how effective they are at reducing the percentages of overweight and obesity among children. Findings The current research shows the existence of counteracting efforts at the micro (family) and macro (governmental policies) levels that need to be aligned to reduce rates of obesity and overweight. Practical implications The systems perspective supports decision makers in defining social marketing strategies to modify alimentary behaviors based on the understanding of what elements of the SEF influence behavior and how they interrelate. To the authors’ knowledge, a detailed analysis of the influences of the socioecological environment has not been performed based on Latin American countries to seek solutions to the public health problems of overweight and obesity. Originality/value The application of SD enhances the value of the SEF suggested by Collins et al. (2010) for modeling individual behaviors. Moreover, the use of the systems approach for framing and understanding how the interrelationships of socioecological elements derive in synergic or antagonistic effects helps to predict the long-term effect of governmental actions and school interventions.

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Ultrastructural Localization of Acid Mucosubstance in Skeletal Muscle

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060271 ◽

1967 ◽

Vol 25 ◽

pp. 52-53 ◽

Cited By ~ 2

Author(s):

William J. Dougherty ◽

Samuel S. Spicer

Keyword(s):

Striated Muscle ◽

Divalent Cations ◽

Ultrastructural Localization ◽

Major Elements ◽

Frozen Sections ◽

Thorium Dioxide ◽

Iron Solution ◽

Coupling System ◽

Psoas Muscles ◽

Formalin Fixed

In recent years, considerable attention has focused on the morphological nature of the excitation-contraction coupling system of striated muscle. Since the study of Porter and Palade, it has become evident that the sarcoplastic reticulum (SR) and transverse tubules constitute the major elements of this system. The problem still exists, however, of determining the mechamisms by which the signal to interdigitate is presented to the thick and thin myofilaments. This problem appears to center on the movement of Ca++ions between myofilaments and SR. Recently, Philpott and Goldstein reported acid mucosubstance associated with the SR of fish branchial muscle using the colloidal thorium dioxide technique, and suggested that this material may serve to bind or release divalent cations such as Ca++. In the present study, Hale's iron solution adapted to electron microscopy was applied to formalin-fixed myofibrils isolated from glycerol-extracted rabbit psoas muscles and to frozen sections of formalin-fixed rat psoas muscles.

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Molecular architecture and functions of the neuronal cytoskeleton

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100157541 ◽

1990 ◽

Vol 48 (3) ◽

pp. 2-3

Author(s):

Nobutaka Hirokawa

Keyword(s):

Major Elements ◽

Molecular Structures ◽

Organelle Transport ◽

Molecular Architecture ◽

Neuronal Morphogenesis ◽

Microtubule Associated Proteins ◽

Associated Proteins ◽

And Function ◽

Small Clusters

In this symposium I will present our studies about the molecular architecture and function of the cytomatrix of the nerve cells. The nerve cell is a highly polarized cell composed of highly branched dendrites, cell body, and a single long axon along the direction of the impulse propagation. Each part of the neuron takes characteristic shapes for which the cytoskeleton provides the framework. The neuronal cytoskeletons play important roles on neuronal morphogenesis, organelle transport and the synaptic transmission. In the axon neurofilaments (NF) form dense arrays, while microtubules (MT) are arranged as small clusters among the NFs. On the other hand, MTs are distributed uniformly, whereas NFs tend to run solitarily or form small fascicles in the dendrites Quick freeze deep etch electron microscopy revealed various kinds of strands among MTs, NFs and membranous organelles (MO). These structures form major elements of the cytomatrix in the neuron. To investigate molecular nature and function of these filaments first we studied molecular structures of microtubule associated proteins (MAP1A, MAP1B, MAP2, MAP2C and tau), and microtubules reconstituted from MAPs and tubulin in vitro. These MAPs were all fibrous molecules with different length and formed arm like projections from the microtubule surface.

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A Dynamic Systems Approach to Personality

European Psychologist ◽

10.1027//1016-9040.6.3.172 ◽

2001 ◽

Vol 6 (3) ◽

pp. 172-176 ◽

Cited By ~ 14

Author(s):

Lawrence A. Pervin

Keyword(s):

Dynamic Systems ◽

Systems Approach ◽

Biological Processes ◽

Recent Advances ◽

Dynamic View ◽

The Future ◽

History Of

David Magnusson has been the most articulate spokesperson for a holistic, systems approach to personality. This paper considers three concepts relevant to a dynamic systems approach to personality: dynamics, systems, and levels. Some of the history of a dynamic view is traced, leading to an emphasis on the need for stressing the interplay among goals. Concepts such as multidetermination, equipotentiality, and equifinality are shown to be important aspects of a systems approach. Finally, attention is drawn to the question of levels of description, analysis, and explanation in a theory of personality. The importance of the issue is emphasized in relation to recent advances in our understanding of biological processes. Integrating such advances into a theory of personality while avoiding the danger of reductionism is a challenge for the future.

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